The Search for Universal Ethics:
A New Look at Natural Law*

International Theological Commission

translated by Joseph Bolin

Revised on March 25, 2010

This translation is an unofficial, literal translation of the text. Comments are welcome by email or by posting a comment on my blog. Permission to reproduce this translation is granted for personal or academic purposes. Please contact Joseph Bolin to inquire about other uses.

Table of contents




1.1. The wisdoms and religions of the world
1.2. The Greco-Roman sources of natural law
1.3. The teaching of Sacred Scripture
1.4. The development of the Christian tradition
1.5. Further developments
1.6. The Magisterium of the Church and the natural law


2.1. The role of society and culture
2.2. Moral experience: "one must do good"
2.3. The discovery of the precepts of the natural law: universality of the natural law
2.4. The precepts of the natural law
2.5. The application of the common precepts: historicity of the natural law
2.6. The moral dispositions of the person and his concrete action


3.1. From experience to theory
3.2. Nature, person and freedom
3.3. Nature, man and God: from harmony to conflict
3.4. Ways towards a reconciliation


4.1. The person and the common good
4.2. Natural law, measure of the political order
4.3. From natural law to natural right
4.4. Natural right and positive law
4.5. The political order and the eschatological order
4.6. The political order is a temporal and rational order


5.1. The Incarnate Logos, living law
5.2. The Holy Spirit and the new law of freedom



1. Are there objective moral values capable of bringing people together and securing peace and happiness for them? What are they? How are they recognized? How are they realized in the life of individuals and of the community? These questions about good and evil, questions which always return, are today more urgent than ever, in as much as people are more aware of forming a single community in the world. The great problems that present themselves to human beings now bear an international, planetary dimension, since the development of the techniques of communication favors a growing interaction between persons, societies, and cultures. A local event can have a planetary resonance almost immediately. Thus there appears the awareness of a global solidarity, which has its ultimate foundation in the unity of the human race. This translates into a planetary responsibility. Thus the problems of ecological equilibrium, of the protection of the environment, of natural resources and of the climate have become pressing concerns, which call upon all humanity and whose solution goes quite beyond national boundaries. Also the threats of terrorism, organized crime and the new forms of violence and of oppression that weigh upon society have a planetary dimension. The rapid developments in biotechnology, which threaten the very identity of the human being (genetic manipulation, cloning, etc.), urgently demand an ethical and political reflection of universal breadth. In this context, the search for common ethical values becomes once more a current issue.

2. With their wisdom, their generosity and sometimes their heroism, men and women are living witnesses to such common ethical values. The admiration that they arouse in us is the sign of a first spontaneous acquisition of moral values. The reflections of academics and of scientists concerning the cultural, political, economic, moral and religious dimensions of our social existence nourish such deliberation about the common good of humanity. There are also the artists who, with the manifestation of beauty, react against the destruction of sensibility and renew the hope of human beings. Politicians, too, work with energy and creativity to make up-to-date programs for the eradication of poverty and the protection of fundamental freedoms. Very important, too, is the constant testimony of representatives of religions and spiritual traditions that seek to live in the light of the ultimate truth and of the absolute good. They all contribute, each in his or her own way and in a reciprocal exchange, to the promotion of peace, of a more just political order, of the sense of common responsibility, of a fair distribution of wealth, of respect for the environment, the dignity of the human person and his or her fundamental rights. Yet these efforts can succeed only if good intentions are based on a sturdy basic agreement concerning the goods and values that represent the most profound aspirations of the human being, individually and in community. Only the acknowledgment and promotion of these ethical values can contribute to the construction of a more human world.

3. The search for a common ethical language concerns everyone. For Christians, it is in mysterious harmony with the work of the Word of God, "the true light, that enlightens every man" (Jn 1:9), and with the work of the Holy Spirit who inspires in hearts "love, joy, peace, magnanimity, benevolence, goodness, fidelity, meekness, self-control" (Gal 5:22-23). The community of Christians, which shares "the joys and hopes, the sorrows and the anguish of the people of today" and "therefore feels really and intimately in solidarity with the whole human race and with its history,"1 cannot be absolutely separated from such common responsibility. Enlightened by the Gospel, engaged in a patient and respectful dialogue with all men of good will, Christians partake in the common search for human values to promote: "That which is true, noble, just, pure, lovable, honorable, that which is virtue or that which deserves praise, think about these things" (Phil 4:8). They know that Jesus Christ, "our peace" (Eph 2:14), who reconciled all men with God through the cross, is the principle of a more profound unity, to which the human race is called to converge.

4. The search for a common ethical language is inseparable from a hope of conversion, with which individuals and the community detach themselves from the forces that seek to imprison the human being in indifference or drive him to raise walls against others or against foreigners. The heart of stone – cold, inert and indifferent to the lot of one's neighbour or of the human race – must be transformed, under the action of the Spirit, into a heart of flesh,2 sensible to the calls of wisdom, to compassion, to the desire for peace and to hope for all. This conversion is the condition for a true dialogue.

5. Contemporary attempts to define a universal ethic are not lacking. After the end of the Second World War, the community of nations, drawing the consequences of the strict complicity that totalitarianism had held with pure juridical positivism, defined in the Universal declaration of human rights (1948) some inalienable rights of human beings that transcend the positive laws of states and which should be kept as a reference and norm. Such rights are not simply granted by the legislator: they are declared, that is, the objective existence that they have already have, prior to the ruling of the legislator, is made manifest. In fact they derive from "the acknowledgment of the dignity inherent in all the members of the human family" (Preamble).

The Universal declaration of human rights constitutes one of the finest successes of modern history. It "remains one of the highest expressions of the human conscience in our time"3 and offers a solid basis for promoting a more just world. Nevertheless the results have not always matched the height of the hopes. Some countries have contested the universality of such rights, judged them to be too western, and this impels the search for a more comprehensive formulation. Further, a certain propensity to multiply the rights of man, in the service more of inordinate desires of the individual consumer or of sector-based demands than of the objective requirements of the common good of humanity, has contributed more than a little to devalue these rights. Separated from the moral sense of values that transcend particular interests, the multiplication of procedures and of juridical regulations leads only to a mire that ultimately serves only the interests of the strongest. Above all, a tendency is manifest to reinterpret the rights of man by separating them from the ethical and rational dimension that constitutes their foundation and their end, to the profit of a pure utilitarian legalism.4

6. To illustrate the ethical foundation of human rights, some have tried to elaborate a "global ethics" in the sphere of a dialogue between cultures and religions. "Global ethics" indicates the ensemble of fundamental obligatory values that for ages have formed the treasure of human experience. We find them in all the great religious and philosophical traditions.5 This project, worthy of interest, is an expression of the present need for an ethics that would have universal and global validity. But can the purely inductive search, on the parliamentary model, of a minimal already existing consent, satisfy the requirements to base law on what is absolute? Further, does such a minimal ethic not perhaps lead to the relativization of the strong ethical needs of every particular religion or wisdom tradition?

7. For many decades the fundamental ethical questions of law and of politics were sidelined in some sectors of contemporary culture. With the pretext that every claim to an objective and universal truth would be a source of intolerance and violence, and that only relativism could safeguard the pluralism of values and democracy, an apologetic is made for a juridical positivism that rejects an objective, ontological criterion of what is just. In this perspective, the final horizon of law and of the moral norm is the law currently in force, which is considered just by definition, being the expression of the will of the legislator. But this seems to open the way to the arbitrariness of power, to the dictatorship of the statistical majority and to ideological manipulation, to the detriment of the common good. "In the present ethics and philosophy of law, the postulates of juridical positivism are widely present. The consequence is that the legislation often becomes only a compromise between different interests; one attempts to transform them into legal interests or private desires that are opposed to the responsibilities deriving from social responsibility."6 But juridical positivism is notoriously insufficient, since the legislator can act legislatively only within the fixed limits that derive from the dignity of the human person, and for the service of authentic human growth. Now the legislator cannot give up the distinction between what is human and what are extrinsic and superficial criteria, as he would, for example, if he accepted as legitimate everything that is doable in the sphere of biotechnology. Finally, one must act in an ethically responsible manner. Politics cannot prescind from ethics nor can the civil law and the juridical order prescind from a higher moral law.

8. In this context, when reference to objective, universally acknowledged values has become problematic, some, desiring to give a common rational basis to common ethical decisions, promote an "ethics of discussion" in the line of a comprehensive "dialogical method" of morals. The ethics of discussion consists in using, in the course of an ethical debate, only the norms to which all the interested parties, renouncing "strategic" behaviors to impose their own points of view, are able to give their assent. Thus one can determine whether a rule of conduct and of action or a behavior are moral, since, setting aside the cultural and historical conditions, the principle of discussion offers a guarantee of universality and of rationality. The ethics of discussion is interested above all in the method with which, for the sake of debate, principles and ethical norms can be put to the test and become obligatory for all the participants. It is essentially a procedure to test the validity of the proposed norms, but it cannot produce substantial new content. The ethics of discussion is therefore a purely formal ethics, which does not regard the moral guidelines at root. It also runs the risk of being limited to a search for compromise. Certainly, dialogue and debate are always necessary to attain a realizable accord on the concrete application of moral norms in a given situation, but it cannot neglect the moral conscience. A true debate does not substitute for personal moral convictions, but it presupposes and enriches them.

9. Aware of the current positions on the table in this question, in this document we intend to invite all who ask themselves about the ultimate foundations of ethics and of the juridical and political order, to consider the resources that a renewed presentation of the teaching of the natural law contains. This affirms in substance that human beings and human communities are capable, by the light of reason, of knowing the fundamental guidelines for moral action in conformity with the very nature of the human subject, and of expressing them in a normative manner, in the form of precepts or commandments. Such fundamental precepts, objective and universal, are needed to found and to inspire the ensemble of the moral, juridical, and political determinations that regulate the life of man and of society. They constitute a permanent, decisive authority and assure the dignity of the human person in the face of fluctuations of ideology. In the course of its history, in the elaboration of its own ethical tradition, the Christian community, guided by the Spirit of Jesus Christ and in critical dialogue with the wisdom traditions that it encountered, has taken up, purified and developed such a teaching on natural law as a fundamental ethical norm. But Christianity does not have a monopoly on the natural law. In fact the natural law, founded on reason, which is common to all human beings, is the basis for collaboration between all men of good will, beyond their religious convictions.

10. It is true that the expression "natural law" is the source of many misunderstandings in the current context. Sometimes it refers to a resigned and completely passive submission to the physical laws of nature, while the human being, on the other hand, justly seeks to master and to order these determinisms for his own good. Once it is presented as an objective given that thrusts itself from the exterior upon the personal conscience, independent of the work of reason or of subjectivity, it is suspected of introducing a form of heteronomy incompatible with the dignity of the free human person. Again, in the course of history, Christian theology has too easily justified with the natural law anthropological positions which, consequently, have appeared conditioned by their historical and cultural context. But a more profound understanding of the rapport between the moral subject, nature, and God, as also a better consideration of the historicity with regard to the concrete application of the natural law, allow one to disperse such misunderstandings. Today it is also important to propose the traditional doctrine of the natural law in terms that better manifest the personal and existential dimension of the moral life. It is also necessary to insist more strongly on the fact that the expression of the exigencies of the natural law is inseparable from the endeavor of the whole of the human community to overcome egoistic and factional tendencies and to develop a global approach with the "ecology of values," without which human life risks losing its own integrity and its own sense of responsibility for the good of all.

11. The idea of the natural moral law takes up numerous elements common to humanity's great wisdom traditions, both religious and philosophical. For this reason our document, in the first chapter, begins by recalling this "convergence." Without claiming to be exhaustive, it indicates that these great religious and philosophical traditions are witnesses to the existence of a largely common moral patrimony, which forms the basis of all dialogue on moral questions. Still more, they suggest, in one way or another, that this patrimony makes explicit a universal ethical message inherent in the nature of things and that everyone is able to decipher. The document then recalls some essential points of reference for the historical development of the idea of natural law and mentions some modern interpretations that are partially at the origin of the difficulties that our contemporaries experience regarding this notion. In chapter 2 ("The perception of common moral values"), our document describes how, beginning from the simplest data of moral experience, the human person gathers immediately some fundamental moral goods and consequently formulates the precepts of the natural law. These do not constitute a complete codex of inviolable prescriptions, but an abiding and normative principle of inspiration at the service of the concrete moral life of the person. Chapter 3 ("The foundations of natural law"), passing from common experience to theory, deepens the philosophical, metaphysical, and religious foundations of the natural law. To answer some contemporary objections, it clarifies the role of nature in personal action and examines the possibility of nature establishing a moral norm. Chapter 4 ("Natural law and the city") explains the regulatory role of the precepts of natural law in political life. The doctrine of natural law possesses coherence and validity on the philosophical plane of reason common to everyone, but chapter 5 ("Jesus Christ, fulfillment of the natural law") shows that it acquires its full sense within the history of salvation: in fact Jesus Christ, sent by the Father, is, with his Spirit, the fullness of every law.

Chapter 1: Convergences

1.1. The wisdom traditions and religions of the world

12. In the different cultures, people have progressively elaborated and developed traditions of wisdom in which they express and transmit their vision of the world, as also their reflected perception of the place that the human being occupies in society and in the world. Before all conceptual theorizing, these wisdom traditions, which are often of a religious nature, transmit an experience which identities that which favors or impedes the full manifestation of personal life and the good course of social life. They constitute a sort of "cultural capital" available for the search for a common wisdom that is necessary to answer the contemporary ethical challenges. According to the Christian faith, these wisdom traditions, in spite of their limits and sometimes their errors, catch a reflection of the divine wisdom that works in the human heart. They require attention and respect, and can have value for a praeparatio evangelica.

The form and the extension of these traditions can vary considerably. Still they are witnesses to the existence of a patrimony of moral values common to all people, beyond the manner in which such values are justified within a particular vision of the world. For example, the "golden rule" ("Do not do to anyone what you do not want done to you" [Tob 4:15]) is found, in one form or another, in the majority of the wisdom traditions.7 Further, they generally agree in the recognition that the great ethical rules are not imposed by a determinate human group, but are universally valid for every individual and for all people. Finally, many traditions recognize that these universal moral behaviors are required by the very nature of the human being: they express the manner in which man should insert himself, in a creative and harmonious manner, in a cosmic or metaphysical order that surpasses it and gives meaning to his life. In fact this order is impregnated by an immanent wisdom. It is the bearer of a moral message that everyone is able to decipher.

13. In the Hindu traditions the world – the cosmos and human societies – is regulated by a fundamental order or law (dharma) that must be respected in order to avoid grave imbalances. For this reason the dharma defines man's socio-religious obligations. In its specificity, the moral teaching of Hinduism is comprehended in the light of the traditional doctrine of the Upanishads: the belief in an indefinite cycle of transmigrations (samsāra), with the idea that good or bad actions done in the present life (karma) influence successive rebirths. These doctrines have important consequences for behavior as regards other persons: they imply a deep degree of goodness and tolerance, the meaningfulness of disinterested action for the benefit of others, as also the practice of non-violence (ahimsā). The principal current of Hinduism distinguishes two bodies of texts: šruti ("that which is heard", namely revelation) and smriti ("that which is remembered", namely the tradition). The ethical prescriptions are found above all in the smrti, more particularly in the dharmaśāstra (the most important of which are the mānava dharmaśāstra or the laws of Manu, of 200-100 B.C.). Beyond the basic principle - according to which "immemorial custom is the transcendent law approved by sacred scripture and by the codices of the divine legislators; for this reason every man of the three principal classes, who respects the supreme spirit which is in him, should always conform himself diligently to immemorial custom"8 - is found an equivalent of the golden rule: "I will tell you what constitutes the highest good of a human being. The man who practices the religion (dharma) of universal non-violence (ahimsā) achieves his highest good. This man who controls himself in the three passions, namely cupidity, anger, and avarice, renouncing them in relation to all that exists, attains to success. (...) That man who regards all creatures as his "own self" and treats them as himself, setting aside the punishing rod and completely controlling his anger, assures for himself the possession of happiness. (...) You shall not do to another what you regard as harmful for yourself. This is in brief the rule of virtue. (...) In the act of refusing and giving, in happiness and misery, in the agreeable and the disagreeable, one shall judge of all their effects by considering one's own 'self.' "9 Different precepts of the Hindu tradition can be put in parallel with the requirements of the Decalogue.10

14. One generally defines Buddhism by the four "noble truths" taught by Buddha after his illumination: (1) reality is suffering and dissatisfaction; (2) the origin of suffering is desire; (3) the cessation of suffering is possible (by the extinction of desire); (4) there is one way that leads to the cessation of suffering. This way is the 'noble eightfold path' which consists in the practice of discipline, concentration and wisdom. On the ethical plane one can summarize favorable actions in the five precepts (śīla, sīla): (1) not to harm any living being and not to take life; (2) not to take that which is not given; (3) not to practice sexual misconduct; (4) not to speak false words or to lie; (5) not to drink intoxicating products that diminish self-control. The profound altruism of the Buddhist tradition, which translates into a deliberate attitude of non-violence, into friendly benevolence and compassion, thus summarizes the golden rule.

15. The Chinese civilization is profoundly marked by the Taoism of Laozi or Lao-Tse (6 century B.C.) According to Lao-Tse, the Way or Tao is the primordial principle, immanent in the whole universe. It is an elusive principle of continual change under the action of two contrary and complementary poles: the yin and the yang. It pertains to man to espouse this natural process of transformation, allowing himself to go with the flow of time, thanks to the attitude of non-action (wú-wéi). The search for harmony with nature, indissolubly material and spiritual, is therefore at the heart of the Taoist ethics. Confucius (571-479 B.C.), ("Master Kong"), on the occasion of a period of profound crisis, tried to restore order with regard to the rites, based on the filial piety that should be at the heart of all social life. In fact social relations are modeled on familial relations. Harmony is obtained by an ethics of equitable measure, in which the ritualized relation (the li) that inserts the human being into the natural order is the measure of all things. The ideal to be attained is the ren, perfect virtue of humanity, attained by self-control and by benevolence towards all others. Is not 'meekness' (shù) perhaps the key word? That which you would not want done to you, do not inflict on another"11). The practice of this rule indicates the way of Heaven (Tiān Dào).

16. In the African traditions, the fundamental reality is life itself. It is the most precious good, and the human ideal consists not only in living unto old age sheltered from worries, but above all in remaining, even after death, a vital force continually strengthened and revitalized in and through one's progeny. In fact life is a dramatic experience. The human being, microcosm within the macrocosm, lives intensely the drama of the clash between life and death. The task that falls to him, of assuring the victory of life over death, orients and determines his ethical action. Thus man should identify, in a consequent ethical horizon, the allies of life, gaining them to his cause and thus assuring his own survival which is at the same time the victory of life. This is the profound meaning of the traditional African religions. The African ethics is thus revealed as an anthropocentric and vital ethics: acts seen as suitable for favoring the opening up of life, for preserving and protecting it, for developing and increasing the living potential of the community are therefore considered good; every act considered harmful to the life of individuals or of the community is judged to be bad. Traditional African religions thus appear essentially anthropocentric, but attentive observation and reflection shows that neither the place acknowledged for living man nor the cult of the ancestors constitutes any thing closed in on itself. Traditional African religions achieve their apex in God, source of life, creator of all that exists.

17. Islam sees itself as the restoration of the original natural religion. It sees in Mohammad the last prophet sent by God to lead man definitively back to the right way. Mohammad, however, was preceded by others: "There is not a community in which someone has not passed to raise a warning."12 Islam therefore attributes to itself a universal vocation and addresses all men and women, who are considered "naturally" muslims. The Islamic law, indissolubly communitarian, moral, and religious, is understood as a law given directly by God. The Muslim ethic is therefore fundamentally a morality of obedience. To do good means to obey the commandments; to do evil means to disobey them. Human reason intervenes to recognize the revealed character of the Law and to derive concrete juridical implications from it. Certainly, in the ninth century, the Mu’tazilita school proclaimed the idea according to which "good and evil are in things," i.e., some behaviors are good or bad in themselves, prior to the divine law that commands or prohibits them. The Mu'tazilis judged that human beings can recognize what is good or bad by the use of reason. According to them, man knows spontaneously that injustice or lying is bad, and that one is obliged to repay a loan, removing oneself from a loss, or showing oneself as appreciative towards one's benefactors, the first of whom is God. But the Ash’arites, who dominate Sunnite orthodoxy, have upheld a contrary theory. Proponents of an occasionalism that does not recognize any consistency in nature, they judge that only God's positive revelation defines good and bad, just and unjust. From the prescriptions of this positive divine law many persons regain the great elements of the moral patrimony of humanity and they can be set in relation to the Decalogue.13

1.2. The Greco-Roman sources of the natural law

18. The idea that there is a natural law prior to all positive juridical determinations is already found in classic Greek culture with the exemplary figure of Antigone, the daughter of Oedipus. Her two brothers, Eteocles and Polyneices, run afoul of the authority and are both killed. Polyneices, the rebel, is condemned to remain unburied and to be burned on the pyre. But Antigone, to fulfill the duty of piety towards the dead brother, pleads, against the prohibition of burial pronounced by king Creon, to "unwritten and immutable laws."

Creonte: And so, you have dared to violate my laws?
Antigone: Yes, because Zeus has not proclaimed them
Nor justice which dwells with the gods of the netherworld;
Neither the one nor the other has laid them down for men.
I do not judge that your decrees are so strong
that you, a mortal, can pass beyond
the unwritten and immutable laws of the gods.
They exist not since today or yesterday, but always:
No one knows when they appear.
Out of fear of the will of a man
It was not right for me to risk the gods punishing me.14

19. Plato and Aristotle took up the distinction made by the sophists between the laws that originate by convention, that is by a purely positive decision (thesis), and those which have force "by nature". The first are neither eternal nor are they in force universally, and are not binding on all. The second are binding on all, always and everywhere.15 Some sophists, such as Callicles of the Gorgias of Plato, turned to this distinction to contest the legitimacy of the established laws of the human city. To such laws they opposed their idea, narrow and erroneous, of nature, reduced to solely the physical component. Thus, against the political and juridical equality of the citizens in the City, they held what seemed to them the most evident of the "natural laws": the strong should prevail over the weak.16

20. None of this is in Plato and Aristotle. They do not oppose natural law and the positive laws of the City. They are convinced that the laws of the City are generally good and constitute the realization, more or less successful, of a natural law in conformity with the nature of things. For Plato the natural law is an ideal law, a norm for legislators and for citizens, a rule that allows them to establish and to evaluate positive laws.17 For Aristotle this supreme norm of morality corresponds to the realization of the essential form of nature. That is moral which is natural. Natural law is immutable; positive law changes according to different peoples and epochs. But natural law is not simply separate from positive law. It is incarnate in positive law, which is the application of the general idea of justice to social life in its variety.

21. In Stoicism natural law becomes the key concept of a universalist ethics. That which is good and ought to be done is that which corresponds to nature, understood both in a physico-biological and in a rational sense. Every man, whatever the nation to which he belongs, should be integrated as a part of the whole universe. He ought to live according to nature.18 This imperative presupposes that there is an eternal law, a divine Logos, which is present both in the cosmos, which it impregnates with rationality, and in human reason. Thus, for Cicero the law is "the supreme reason inserted in nature which enjoins on us what must be done and prohibits the contrary".19 Nature and reason constitute the two sources of our knowledge of the fundamental ethical law, which is of divine origin.

1.3. The teaching of Sacred Scripture

22. The gift of the Law on Sinai, of which the "Ten Commandments" constitute the center, is an essential element of the religious experience of Israel. This Law of the covenant includes fundamental ethical precepts. They define the manner in which the chosen people respond to the choice of God by the holiness of their lives: "Speak to all the congregation of the people of Israel, saying to them: 'You shall be holy; for I the Lord your God am holy'" (Lev 19:2). But these ethical behaviors are valid for all other peoples, so that God calls to account all foreign nations that violate justice and right.20 In fact God had already established in the person of Noah a covenant with the entire human race, which implied respect for life in particular (Gen 9).21 More fundamentally, creation itself appears as the act by which God structures the whole universe, giving it a law. "Let them [the stars] praise the name of the LORD! For he commanded and they were created. And he established them for ever and ever; he fixed their bounds which cannot be passed (Psa 148:5-6). This obedience of created things to the law of God is a model for human beings.

23. As well as the texts that recount the history of salvation, with the major theological themes of election, promise, law and the covenant, the Bible contains also a wisdom literature that does not treat directly of the national history of Israel, but that deals with the place of man in the world. It develops the conviction that there is a correct way, a "wisdom," of doing things and of living one's life. The human being should commit himself to seeking it and then striving to put it into practice. This wisdom is not found so much in history as in nature and in everyday life.22 In this literature, wisdom is often presented as a divine perfection, sometimes hypostasized. It is manifested in an eminent manner in creation, of which it is the "artificer" (Wis 7:21). The harmony that reigns among creatures bears witness to it. Of this wisdom that comes from God man is rendered a partaker in different ways. This participation is a gift of God, which one must ask for: "I prayed, and understanding was given me; I called upon God, and the spirit of wisdom came to me" (Wis 7:7). It is also the fruit of obedience to the revealed law. Indeed the Torah is the incarnation of wisdom. "If you desire wisdom, keep the commandments, and the Lord will supply it for you. For the fear of the Lord is wisdom and instruction" (Sir 1:26-27). But wisdom is also the result of shrewdly observing nature and human customs in order to discover their immanent intelligibility and their exemplary value.23

24. In the fullness of time, Jesus Christ preached the coming of the Kingdom as the manifestation of the merciful love of God, which makes itself personally present in mankind, and asks a conversion and free response of love from them. This preaching is not without consequences for ethics, for the manner of building the world and human relations. In its moral teaching, of which the Sermon on the Mount is an admirable synthesis, Jesus himself takes up the golden rule: "Whatever you wish that men would do to you, do so to them; for this is the law and the prophets" (Matt 7:12).24 This positive precept completes the negative formulation of the same rule in the Old Testament: "Do not do to anyone what you do not want done to you" (Tobit 4:15).25

25. At the beginning of the Letter to the Romans, the apostle Paul, intending to show the universal necessity of the salvation brought by Christ, describes the religious and moral situation common to all men. He affirms the possibility of a natural knowledge of God: "What can be known about God is plain to them, because God has shown it to them. Ever since the creation of the world his invisible nature, namely, his eternal power and deity, has been clearly perceived in the things that have been made" (Rom 1:19-20).26 But this knowledge has been perverted in idolatry. Placing Jews and pagans on the same level, St. Paul affirms the existence of an unwritten moral law, which is written in their hearts.27 It gives each one the ability to discern good and evil. "When Gentiles who have not the law do by nature what the law requires, they are a law to themselves, even though they do not have the law. They show that what the law requires is written on their hearts, while their conscience also bears witness and their conflicting thoughts accuse or perhaps excuse them" (Rom 2:14-15). The knowledge of the law, however, is not enough of itself to lead a righteous life.28 These texts of St. Paul have had a decisive influence on the Christian reflection in regard to natural law.

1.4. The development of the Christian tradition

26. For the Fathers of the Church the sequi naturam and the sequela Christi are not opposed. On the contrary, they adopt generally the stoic idea according to which nature and reason indicate to us what our moral duties are. To follow them is to follow the personal Logos, the Word of God. In fact the doctrine of natural law furnishes a foundation that complements biblical morals. It further allows one to illustrate why the pagans, independently of the biblical revelation, possess a positive moral conception. This is indicated to them by nature and corresponds to the teaching of Revelation: "From God are the law of nature and the law of revelation, which form a whole".29 Still the Fathers of the Church do not adopt purely and simply the stoic doctrine, but modify and develop it. On the one hand, the anthropology of biblical inspiration that sees man as the imago Dei, the full truth of which is manifested in Christ, forbids the reduction of the human person to a simple element of the cosmos: called to communion with the living God, the human person transcends the cosmos while integrating himself in it. On the other hand, the harmony of nature and reason is not based any more on an immanentistic vision of a pantheistic cosmos, but on the common reference to the transcendent wisdom of the Creator. To behave in a manner in conformity with reason means to follow the orientations that Christ, as the divine Logos, has placed, by way of the logoi spermatikoi, in the human reason. To act contrary to reason is a disturbance of these orientations. The definition of St. Augustine is very significant: "The eternal law is the divine reason or will of God, which orders and preserves the natural order and prohibits disturbing it".30 More precisely, for St. Augustine the norms of a right life and of justice are expressed in the Word of God, which then imprints them in the human heart "in the manner of a seal that a ring makes in wax, but without leaving the ring".31 Further, in the Fathers natural law is now apprehended in the environment of a history of salvation that leads one to distinguish different states of nature (original nature, fallen nature, restored nature), in which natural law is realized in different manners. This patristic doctrine of natural law was handed on to the Middle Ages, together with the conception, very closely related, of the "law of nations (ius gentium)", according to which there exist, apart from Roman law (ius civile), universal principles of law that regulate the relations between peoples and are binding for all.32

27. In the Middle Ages the doctrine of natural law reaches a certain maturity and assumes a "classical" form, which constitutes the foundation of all further discussions of it. It is characterized by four elements. In the first place, in conformity with the nature of scholastic thought, which seeks to gather the truth wherever it is found, it takes up prior reflections on natural law, pagan or Christian, and tries to propose a synthesis. In the second place, in conformity with the systematic nature of scholastic thought, it locates natural law in a general metaphysical and theological setting. Natural law is understood as a participation of the rational creature in the eternal divine law, through which it enters in a free and conscious manner into the plans of Providence. It is not a closed and complete set of moral norms, but a source of constant inspiration, present and operative in the different stages of the economy of salvation. In the third place, with the awareness of the proper weight of nature, which is in part understood in the rediscovery of the thought of Aristotle, the scholastic doctrine of natural law considers the ethical and political order as a rational order, a work of human intelligence. It defines for it a space of autonomy, a distinction without separation, in a relationship with the order of religious revelation.33 Finally, in the eyes of scholastic theologians and jurists, natural law constitutes a point of reference and a criterion in the light of which they evaluate the legitimacy of positive laws and of particular customs.

1.5. Further developments

28. The modern history of the idea of natural law is seen in certain respects as a legitimate development of the teaching of medieval scholasticism in a more complex cultural context, marked in particular by a more vivid sense of moral subjectivity. Among these developments, we point out the works of the Spanish theologians of the 16th century, which, in the manner of the Dominican Francis of Vitoria, resorted to natural law to contest the imperialist ideology of some Christian states of Europe and to defend the rights of the non-Christian peoples of America. In fact these rights are inherent in human nature and do not depend on the concrete situation regarding the Christian faith. The idea of natural law further allowed the Spanish theologians to establish the groundwork of an international law, i.e., of a universal norm that regulates the mutual relations of peoples and states.

29. But in other respects the idea of natural law took turns and forms in the modern age that make it difficult to accept today. In the last centuries of the Middle Ages, there developed in scholasticism a current of voluntarism, whose cultural hegemony profoundly modified the idea of natural law. Voluntarism proposes to value the transcendence of the free subject in relation to all conditioning. Against naturalism, which tended to subject God to the laws of nature, it underlines unilaterally the absolute freedom of God, with the risk of compromising his wisdom and rendering his decisions arbitrary. Further, against intellectualism, suspected of subjecting the human person to the order of the world, it exalts a freedom of indifference understood as a pure potency for choosing contraries, at the risk of detaching the person from his natural inclinations and from the objective good.34

30. The consequences of voluntarism for the doctrine of natural law are numerous. Above all, while in Thomas Aquinas the law was understood as a work of reason and an expression of wisdom, voluntarism leads one to connect the law to will alone, and to a will detached from its intrinsic ordering to the good. Then all the force of the law resides only in the will of the legislator. The law is thus expropriated of its intrinsic intelligibility. In these conditions, morality is reduced to obedience to the commandments, which manifest the will of the legislator. Thomas Hobbes explains it thus: "It is authority and not truth that makes law (auctoritas, non veritas, facit legem)".35 Modern man, loving autonomy, was not able not to rebel against such a vision of the law. Then, with the pretext of preserving the absolute sovereignty of God over nature, voluntarism deprived it of all internal intelligibility. The thesis of the potentia Dei absoluta, according to which God could act independently of his wisdom and his goodness, relativizes all existing intelligible structures and weakens the natural knowledge that man can have of them. Nature ceases to be a criterion for knowing the wise will of God: man can receive such knowledge only by a revelation.

31. On the other hand, several factors led to the secularization of the notion of natural law. Among these, one can recall the growing divorce between faith and reason which characterizes the end of the Middle Ages, or some aspects of the Reformation,36 but above all the will to overcome the violent religious conflicts that bloodied Europe up until the dawn of modern times. One came to the point of desiring to establish the political unity of the human communities by parenthesizing religious confession. From this time on the doctrine of the natural law prescinds from all particular revelation, and therefore from all confessional theology. It claims to be founded solely on the lights of reason common to all men and is presented as the ultimate norm in the secular field.

32. Further, modern rationalism posits the existence of an absolute and normative order of intelligible essences accessible to reason and simultaneously relativizes the reference to God as the ultimate foundation of the natural law. The necessary, eternal, and immutable order of essences must certainly be actualized by the Creator, but, it is believed, it possesses in itself its coherence and its rationality. The reference to God must therefore be optional. The natural law would be imposed on all "even if God did not exist (etsi Deus non daretur)".37

33. The modern rationalist model of natural law is characterized: (1) by the essentialist belief in an immutable and ahistorical human nature, of which reason can gather perfectly the definition and essential properties; (2) by parenthesizing the concrete situation of human persons in the history of salvation, marked by sin and by grace, which nonetheless has a decisive influence on the knowledge and practice of natural law; (3) by the idea that it is possible for reason to deduce a priori the precepts of the natural law, beginning from the definition of the essence of the human being; (4) by the maximum extension thus given to those precepts, so much so that the natural law appears as a codex of pre-made laws that regulates as it were the entirety of behaviors. This tendency to extend the field of the determinations of natural law was at the origin of a grave crisis when, particularly with the progress of the human sciences, western thought became more aware of the historicity of human institutions and of the cultural relativity of numerous behaviors that one once justified by appealing tothe obviousness of natural law. This disagreement between an abstract, maximalist theory and the complexity of the empirical data explains in part the dissatisfaction with the very idea of natural law. In order that the notion of natural law may serve the elaboration of a universal ethics in a secularized and pluralistic society such as ours, it is therefore necessary to avoid presenting it in the rigid form that it assumed, particularly in modern rationalism.

1.6. The Magisterium of the Church and the natural law

34. Before the 13th century, because the distinction between the natural and the supernatural order was not clearly elaborated, natural law was generally assimilated to Christian morals. Thus the decree of Gratian, which provides the groundwork canonical norm in the 12th century, begins by affirming: "The natural law is that which is contained in the Law and in the Gospel." It then identifies the content of the natural law with the golden rule and explains that the divine laws correspond to nature.38 The Fathers of the Church therefore had recourse to natural law and to Sacred Scripture to establish the moral behavior of Christians, but the Magisterium of the Church, in these first ages, would have to intervene little to settle disputes on the content of the moral law.

When the Magisterium of the Church was led not only to resolve particular moral debates,but also to justify its own position before a secularized world, it adverted more explicitly to the notion of natural law. In the 19th century, especially during the pontificate of Leo XIII, recourse to the natural law is made in the acts of the Magisterium. The most explicit presentation is found in the encyclical Libertas praestantissimum (1888). Leo XIII refers to natural law to identify the source of civil authority and to fix its limits. He vigorously recalls that one must obey God rather than men when the civil authorities command or allow anything that is contrary to the divine law or the natural law. But he also looks to natural law to protect private property against socialism and to defend the right of workers to procure with their work the means which they need to sustain their life. In this same line, John XXIII refers to the natural law to establish the rights and the duties of man (encyclical Pacem in terris [1963]). With Pius XI (encyclical Casti connubii [1930]) and Paul VI (encyclical Humanae vitae [1968]), natural law is revealed as a decisive criterion in the questions related to conjugal morality. Certainly the natural law is accessible to human reason, common to believers and nonbelievers, and the Church does not have it exclusively, but since revelation takes up the requirements of the natural law, the Magisterium of the Church has been established the guarantor and interpreter of it.39 The Catechism of the Catholic Church (1992) and the encyclical Veritatis splendor (1993) assign a decisive place to the natural law in the exposition of Christian morals.40

35. Today the Catholic Church invokes the natural law in four principal contexts. In the first place, facing the spread of a culture that limits rationality to the positive sciences and abandons the moral life to relativism, it insists on the natural capacity that men have of finding by reason "the ethical message contained in being"41 and of knowing in broad outline the fundamental norms of just action conformed to their own nature and dignity. The natural law thus answers to the requirement of grounding human rights in reason42 and makes possible an intercultural and interreligious dialogue capable of favoring universal peace and avoiding the "clash of cultures." In the second place, facing relativistic individualism, which judges that every individual is the source of his own values and that society results from a mere contract agreed between individuals who choose to establish all the norms themselves, it recalls the natural and objective character, not merely conventional, of the fundamental norms that regulate social and political life. In particular, the democratic form of government is intrinsically bound to stable ethical values, which have their source in the requirements of the natural law and thus do not depend on the fluctuations of the consent of a statistical majority. In the third place, facing an aggressive laicism that wants to exclude believers from public debate, the Church notes that the interventions of Christians in public life on issues that regard the natural law (the defense of the rights of the oppressed, justice in international relations, the defence of life and of the family, religious freedom and freedom of education...) are not of themselves of a confessional nature, but derive from the care which every citizen should have for the common good of society. In the fourth place, facing the menace of the abuse of power, and even of totalitarianism, which juridical positivism conceals and which certain ideologies propagate, the Church recalls that civil laws do not bind in conscience when they contradict natural law, and asks for the acknowledgment of the right to conscientious objection, as also the duty of obedience in the name of obedience to a higher law.43 The reference to natural law not only does not produce conformism, but guarantees personal freedom and defends those marginalized and oppressed by social structures forgetful of the common good.

Second Chapter: The perception of common moral values

36. The examination of the great wisdom traditions detailed in the first chapter shows that some types of human behavior are recognized, in the majority of cultures, as an expression of a certain excellence in the manner in which the human being lives and realizes its own humanity: acts of courage, patience in trials and in the difficulties of life, compassion for the weak, moderation in the use of material goods, a responsible attitude in regard to the environment, dedication to the common good... Such ethical conduct defines the broad outline of a properly moral ideal of a life "according to nature," i.e., in conformity with the profound being of the human subject. On the other hand, some behaviors are universally recognized as objects of reprobation: murder, theft, lying, wrath, greed, avarice... These appear as attacks on the dignity of the human person and on the just requirements of life in society. One is justified therefore in seeing, in such consensus, a manifestation of that which, behind diverse cultures, is the human in the human being, namely the "human nature." But at the same time, one must admit that such accord on the moral quality of certain behaviors coexists with a great variety of explanatory theories. Whether we look at the fundamental doctrines of the Upanishads of Hinduism, or of the four "noble truths" for Buddhism, or the Tao of Lao-Tse, or of the "nature" of the stoics, every school of wisdom or every philosophical system understands moral action within a general explanatory picture that seeks to legitimatize the distinction between what is good and what is evil. We have to deal with a variety of justifications that renders dialogue and the establishing of moral norms difficult.

37. Still, independently of the theoretical justifications of the concept of natural law, it is possible to discover the fundamental elements of the awareness of which it wants to give an account. The object of this chapter is precisely to show how to gather together the common moral values that constitute natural law. We willthen see how the concept of natural law is based on an explanatory picture that founds and legitimizes moral values, in a manner that can be shared by many. To do this, the presentation of the natural law in St. Thomas Aquinas appears particularly pertinent, since, among other things, it places the natural law within a morality that upholds the dignity of the human person and recognizes its capacity of discernment. 44

2.1. The role of society and of culture

38. The human person only progressively comes to moral experience and becomes capable of giving himself the precepts that should guide his action. One attains this in the measure in which from birth one is inserted in a net of human relations, beginning with the family, relations that have allowed one, little by little, to become aware of one's self and of the surrounding reality. One arrives in particular at the apprehension of a language – one's mother tongue – which teaches one to name things and allows one to become a subject aware of oneself. Oriented by the persons that surround one, impregnated by the culture in which one is immersed, the person recognizes certain ways of behaving and of thinking as values to pursue, laws to observe, examples to imitate, visions of the world to accept. The social and culture context thus exercises a decisive role in the education for moral values. Still, such conditions cannot be opposed to human freedom. They rather make it possible, since through them the person can come to moral experience, which eventually allows him to review some of the "evidences" that he had interiorized in the course of his moral apprenticeship. On the other hand, in the context of the present globalization, society and culture themselves must inevitably practice a sincere dialogue and exchange, based on the co-responsibility of all in regard to the common good of the planet: they must allow particular interests to accede to the moral values that all are called to share.

2.2. Moral experience: "one must do good"

39. Every human being who attains to consciousness and responsibility experiences an interior call to do good. He discovers that he is fundamentally a moral being, capable of perceiving and of expressing the call that, as was saw, is found within all cultures: "to do good and avoid evil." On this precept are based all the other precepts of the natural law.45 This first precept is known naturally, immediately, with the practical reason, just as the principle of non-contradiction (the intellect cannot simultaneously and in the same respect affirm and deny the same thing of one subject), which is at the base of all speculative reasoning, is gathered intuitively, naturally, with the theoretical reason, when the subject comprehends the sense of the terms employed. Traditionally, such knowledge of the first principle of the moral life was attributed to an innate intellectual disposition called synderesis.46

40. With this principle, we find ourselves immediately in the sphere of morality. The good that thus imposes itself on the person is in fact the moral good, i.e., a behavior that, exceeding the categories of the useful, is in keeping with the authentic realization of this being, at once one and differentiated, which is the human being. Human activity is irreducible to a simple question of adaption to the "ecosystem"; human being signifies existing and being placed within a broader picture that defines a meaning, values and responsibility. Searching for the moral good, the person contributes to the realization of his nature, beyond impulses of instinct or the search for a particular pleasure. This good testifies to itself and is comprehended from within.47

41. The moral good corresponds to the profound desire of the human person which – as every being – tends spontaneously, naturally, towards realizing itself more fully, towards that which allows it to attain the perfection proper to it, which is happiness. Unfortunately the subject can always allow itself to be swept away by particular good desires and choices or to do deeds that go against the moral good that it recognizes. It can refuse to surpass itself. It is the price of a freedom limited in itself and weakened by sin, a freedom that encounters only particular goods, none of which can fully satisfy the heart of the human being. It pertains to the reason of the subject to examine if these particular goods can be integrated in the authentic realization of the person: in such a case they will be judged morally good, and in the contrary event, morally bad.

42. This last affirmation is of capital importance. It grounds the possibility of a dialogue with persons belonging to different cultural or religious horizons. It shows the eminent dignity of every human person, underlining the natural disposition to know the moral good that should be done. Like every creature, the human person is defined with a set of dynamisms and ends that is prior to the free choice of the will. But, unlike beings that are not endowed with reason, the human person is capable of knowing and of interiorizing such ends, and thus assessing, in light of them, that which is good or bad for it. Thus it recognizes the eternal law, i.e., the plan of God regarding creation, and participates in God's providence in a particularly excellent manner, guiding itself and guiding others.48 This insistence on the dignity of the moral subject and on its relative autonomy is based on the recognition of the autonomy of created reality and joins up with a fundamental given of contemporary culture.49

43. The moral obligation that the subject recognizes does not come, therefore, from a law that would be exterior (as a heteronomy), but affirms itself from within the subject itself. In fact, as indicated by the maxim we have cited – "One must do good and avoid evil" –, the moral good determined by reason "imposes itself" on the subject. It "ought" to be accomplished. It has a character of obligation and of law. But the term "law" here does not refer to scientific laws, which limit themselves to describing the factual constants of the physical or social world, nor to an imperative imposed on the moral subject arbitrarily from without. The law designates here an orientation of the practical reason which indicates to the moral subject what kind of action is conformed with its fundamental dynamism and necessary for its being, which tends to its full realization. This law is normative in virtue of an internal requirement of the spirit. It is born in the very heart of our being as an invitation to the realization and transcending of ourselves. It is not therefore a matter of subjecting oneself to the law of another, but of accepting the law of one's own being.

2.3. The discovery of the precepts of natural law: universality of natural law

44. Once we posit the basic affirmation that introduces us to the moral order – "One must do good and avoid evil" – we see how there arises in the subject the recognition of the fundamental laws that should regulate human action. Such recognition does not consist in an abstract consideration of human nature, nor in the effort to conceptualize, which would be proper to theoretical philosophy and theology. The perception of fundamental moral goods is immediate, vital, based on the connaturality of the spirit with values and engaging both affectivity and intellect, both the heart and the spirit. It is an grasp often imperfect, still obscure and dim, but it has the profundity of immediacy. It deals with the data of the most simple and common experience, which are implicit in the concrete action of persons.

45. In his search for the moral good, the human person sets himself to listen to that which is, and becoming conscious of the fundamental inclinations of his nature, which are quite different from simple blind impulses of desire. Noticing that the goods to which he tends by nature are necessary for his moral realization, he formulates to himself, under the form of practical commands, the moral duty of actualizing them in his own life. He expresses to himself a certain number of general precepts which he shares with all other human beings and which constitute the content of that which we call natural law.

46. One traditionally distinguishes three great sets of natural dynamisms that act in the human person.50 The first, which he has in common with all substances, comprises essentially the inclination to conserve and to develop one's own existence. The second, which he has in common with all living things, comprises the inclination to reproduce, in order to perpetuate the species. The third, which he has as proper to himself, as a rational being, comprises the inclination to know the truth about God and to live in society. From these inclinations can be formulated the first precepts of the natural law, known naturally. Such precepts are very general, but they form the first substratum that is at the foundation of all the further reflections on the good to be practiced and on the evil to be avoided.

47. To leave this generality and to make clear the concrete choices about what to do, it is necessary to have resort to discursive reason, which determines what are the concrete moral goods able to realize the person – and humanity – and formulates more concrete precepts capable of guiding him in his action. In this new stage the knowledge of the moral good proceeds by way of reasoning. At its origin it is very simple: a limited experience of life suffices, and remains within the intellectual possibility of everyone. One speaks here of the "secondary precepts" of the natural law, discovered through a longer or shorter consideration of the practical reason, in contrast to the general fundamental precepts that reason picks up spontaneously and which are called "primary precepts".51

2.4. The precepts of natural law

48. We have identified in the human person the first inclination, which it shares with all beings: the inclination to preserve and to develop its own existence. In living beings there is habitually a spontaneous reaction to an imminent danger of death: one avoids it, one defends the integrity of one's one existence, one struggles to survive. Physical life appears naturally as the fundamental, essential, primordial good: from here is the precept to protect one's own life. Under this precept are gathered inclinations to everything that contributes, in the manner proper to man, to the maintenance and to the quality of biological life: bodily integrity; the use of external goods that assure the sustenance and the integrity of life, such as nourishment, clothing, lodging, work; the quality of the biological environment... Based on these inclinations, the human being proposes goals to be realized, which contribute to the harmonious and responsible development of his own being and which appear to him as moral goods, values to pursue, duties to accomplish and also as rights to be asserted. In fact, the duty to preserve one's own life has as its correlative the right to demand that which is necessary for its preservation in a favorable environment.52

49. The second inclination, which is common to all living beings, regards the survival of the species that is realized by procreation. Generation is inscribed in the prolongation of the tendency to persevere in being. If the perpetuity of biological existence is impossible for the individual, it is possible for the species, and thus it in a certain way overcomes the limits inherent in every physical being. The good of the species appears as one of the fundamental aspirations present in the person. We are particualarly conscious of it in our time, when certain perspectives such as global warming revive our sense of responsibility for the planet as well as for the human species in particular. This opening to a certain common good of the species announces already certain aspirations proper to man. The dynamism towards procreation is intrinsically tied to the natural inclination that brings man to woman and woman to man, a universal datumrecognized in all societies. The same thing is true of the inclination to care for one's children and educate them. These inclinations imply that the permanence of the bond of man and woman and also their reciprocal fidelity are already values to pursue, even if they manifest themselves fully only in the spiritual order of interpersonal communion. 53

50. The third set of inclinations is specific to the human being as a spiritual being, endowed with reason, capable of knowing the truth, of entering into dialogue with others and of forming relations in friendship. There is therefore need to recognize an important particular in this set of inclinations. The inclination to live in society derives above all from the fact that the human being has need of others to overcome his own intrinsic individual limits and to achieve maturity in the various spheres of his existence. But to unfold fully his spiritual nature, he needs to form relations of generous friendship with his fellow human beings and to develop an intense cooperation in seeking the truth. His integral good is thus intimately tied to life in community, which is organized in political society by virtue of a natural inclination and not by mere convention.54 The relational character of the person expresses itself also with the tendency to live in communion with God or the absolute. It manifests itself in religious sentiment and in the desire to know God. Certainly, it can be denied by those who refuse to admit the existence of a personal God, but it remains implicitly present in the search for truth and meaning present in every human being.

51. To these specific tendencies of man corresponds the need perceived by reason to realize concretely this life of relation and to construct life in society on just bases that correspond to natural right. This implies the recognition of the equal dignity of every individual of the human species, beyond the differences of race and culture, and a great respect for humanity wherever it is found, also in the smallest and in the least appreciated of its members. "Do not do to another that which you would not want done to you." We meet here the golden rule, which today is placed as the very principle of a morality of reciprocity. The first chapter allowed us to find the presence of this rule in the majority of the wisdom traditions as well as in the Gospel itself. St. Jerome manifested the universality of several moral precepts by referring to a negative formulation of the golden rule. "It is a just judgment that God wrote in the heart of the human race: 'That which you do not want done to you, do not do to another." Who of us does not know that homicide, adultery, theft and every kind of greed is evil, since we do not want them done to ourselves. If we did not know that these things are bad, we would not ever lament if they are inflicted on us".55 Around the golden rule are gathered the various commandments of the Decalogue, as also many Buddhist precepts, and also many Confucian rules, and even the greater part of the orientations of the great Charters which enumerate the rights of the person.

52. After this brief exposition of the moral principles that derive from reason's consideration of the fundamental inclinations of the human person, we find a set of precepts and values that, at least in their general formulation, can be considered as universal, since they apply to all humanity. They also have the character of immutability to the extent that they derive from a human nature whose essential components remain the same throughout history. It can still happen that they are obscured or even erased from the human heart because of sin and of cultural and historical conditions, which can negatively affect the personal moral life: ideology and insidious propaganda, generalized relativism, structures of sin, etc.56 We must therefore be modest and prudent when invoking the "evidentness" of the precepts of natural law. But we must equally recognize in these precepts the common foundation on which we can base a dialogue with a view to a universal ethics. The protagonists of this dialogue, however, must learn not to consider their own particular interests, to be open to the needs of others, and to allow room for common moral values. In a pluralistic society, in which it is difficult to look to its philosophical foundations, this dialogue is absolutely necessary. The doctrine of natural law can make its contribution to that dialogue.

2.5. The application of the common precepts: historicity of the natural law

53. It is impossible to remain at the general level of the first principles of the natural law. In fact, moral reflection must descend to the concreteness of action to throw its light on it. But to the degree that it confronts more concrete and contingent situations, to that degree its conclusions are more characterized by a note of variability and uncertainty. It is not strange, therefore, that the concrete application of the precepts of natural law can take different forms in different cultures, or also in different epochs within a single culture. It is sufficient to recall the evolution of moral reflection on questions such as slavery, lending at interest, duelling or the death penalty. Sometimes such evolution leads to a better comprehension of moral requirements. Other times, the evolution of the political or economic situation leads to a re-evaluation of particular norms that were formally stable. Morals occupies itself with a contingent reality that evolves through time. Although living in an epoch of Christianity, a theologian such as St. Thomas Aquinas had a very distinct perception of this. "The practical reason – he wrote in the Summa Theologiae – is concerned with contingent reality, which is the object of human actions. Therefore, although the general principles have a certain necessity, the more particular the matters we examine, the more uncertain the conclusions become ... In the sphere of action practical truth or rightness are not the same in all particular applications, but only in the general principles; and where the rightness is the same, it is not equally known by all. ... And here, the more one descends to particulars, the more the indefiniteness grows".57

54. This perspective manifests the historicity of natural law, whose concrete application can vary throughout time. At the same time, it opens the door to the reflection of moralists, inviting them to dialogue and to discussion. This is all the more necessary, since in morality pure deduction by syllogism is not adequate. The more the moralist confronts concrete situations, the more he must have recourse to the wisdom of experience, an experience that integrates the contributions of the other sciences and is nourished by contact with men and women engaged in action. Only this wisdom of experience enables one to take into account the multiplicity of circumstances and to reach a practical conclusion in such a way as to accomplish that which is good hic et nunc. The moralist (this is the difficulty of his work) must have recourse to the combined resources of theology and philosophy, as well as of the humanities, economics and biology, to recognize the data of the situation and to identify correctly the concrete requirements of human dignity. At the same time, he must be particularly attentive to safeguard the fundamental data expressed by the precepts of the natural law that remain the same throughout cultural variation.

2.6. The moral dispositions of the person and his concrete action

55. To reach a just evaluation of the things to be done, the moral subject must be endowed with a certain number of interior dispositions that allow him to be open to the demands of the natural law, and also well informed about the data of the concrete situation. In the context of the present pluralism, we are ever more aware of the fact that one cannot elaborate a morality based on the natural law without also reflecting on the interior dispositions or virtue that render the moralist able to elaborate an adequate norm of action. This is even more true for the subject personally engaged in action, who must formulate a judgment of conscience. It is not strange, then, that today one assists in the rebirth of a "morals of virtue" inspired by the Aristotelian tradition. Thus insisting on the moral qualities required for adequate moral reflection, one comprehends the important role that the various cultures attribute to the figure of the wise man. He enjoys a particular capacity of discernment in the measure in which he possesses the interior moral dispositions that allow him to formulate an adequate ethical judgment. A discernment of this kind should characterize the moralist when he endeavors to concretize the precepts of the natural law, and indeed every autonomous subject responsible for giving a judgment of conscience and formulating the immediate and concrete norm of his action.

56. Morality cannot, therefore, limit itself to producing norms. It should also favor the formation of the subject, so that the subject, engaged in action, may be able to adapt the universal precepts of the natural law to the concrete conditions of existence in diverse cultural contexts. Such a capacity is ensured by moral virtue, in particular by prudence, which integrates all the particular and concrete elements to guide concrete action. The prudent man must possess not only the knowledge of the universal but also of the particular. To indicate well the proper character of this virtue, St. Thomas Aquinas did not hesitate to say: "If one is to have only one of the two kinds of knowledge, it is preferable that it be knowledge of the particular reality that pertains more closely to acting".58 With prudence it is a matter of penetrating a contingent reality that remains always mysterious for reason, of moulding itself to reality in as exact a manner as possible, of assimilating the multiplicity of circumstances, of taking as accurate account as possible of a situation that is original and ineffable. Such an objective requires different operations and abilities that prudence must organize.

57. Still the individual must not lose himself in the concrete and in the individual, as was the rebuke to "situation ethics." He must discover the "right rule of action" and lay down an adequate norm of action. This right rule derives from the preliminary principles. Here one thinks of the first principles of practical reason, but one also turns to the moral virtues to open and render the will and sensible affectivity connatural to the different human goods, and to indicate to the prudent man the ends that he should pursue in the flux of daily life. Only at this point will the individual be able to formulate the concrete norm that imposes itself and to imbue the given action with a ray of justice, of fortitude or of temperance. One could speak here of the exercise of an "emotional intelligence"; the rational powers, without losing their specificity, are at work within the affective field, so that the totality of the person is engaged in the moral action.

58. Prudence is indispensable for the moral subject by reason of the flexibility required in adapting universal moral principles to different situations. But this flexibility does not authorize one to see in prudence a kind of easy compromise in regard to moral values. On the contrary, through prudent decisions the concrete requirements of moral truth for a subject are expressed. Prudence is a necessary passageway to authentic moral obligation.

59. There is here a perspective which, within a pluralist society such as our own, has an importance that cannot be underestimated without suffering significant loss. Indeed, it stems from the fact that moral science cannot furnish an agent subject with a norm that may be applied adequately and almost automatically to concrete situations; only the conscience of the subject, the judgment of his practical reason, can formulate the immediate norm of action. But at the same time it can never abandon the conscience to mere subjectivity: the subject needs to acquire the intellectual and affective dispositions that permit it to open itself to moral truth in such a way that its judgment may be adequate. Natural law cannot, therefore, be presented as an already established set of rules that impose themselves a priori on the moral subject, but is a source of objective inspiration for his process, eminently personal, of making a decision.


Chapter three: the theoretical foundations of natural law

3.1. From experience to theory

60. The spontaneous acquisition of fundamental ethical values, which are expressed in the precepts of the natural law, constitutes the point of departure of the process that then leads the moral subject to the judgment of conscience, in which it enunciates the moral requirements that impose themselves on it in the concrete situation. It is the task of the theologian and of the philosopher to return to this experience of the acquisition of the first principles of ethics, to demonstrate their validity and to ground them in reason. The recognition of these philosophical or theological foundations, however, does not in the least condition the spontaneous adherence to common values. In fact the moral subject can put into practice the orientations of natural law without being capable, by reason of particular intellectual conditions, of explicitly comprehending them and their ultimate theoretical foundations.

61. The philosophical justification of natural law presents two levels of coherence and depth. The idea of a natural law is justified primarily on the basis of reflective observation of the anthropological constants that characterize a successful humanization of the person and a harmonious social life. The reflective experience, transmitted by traditional schools of wisdom, by philosophies or by human sciences, allows one to determine some of the conditions required so that each person may employ better his or her human capacities in personal and communitarian life.59 Thus one recognizes that certain behaviors express an exemplary excellence in the manner of living and of realizing one's own humanity. They define the broad outlines of a properly moral ideal of a virtuous life "according to nature," i.e., in conformity with the profound nature of the human subject.60

62. Still, only by taking into account the metaphysical dimension of reality can we give natural law its full and complete philosophical justification. In fact metaphysics allows one to comprehend that the universe does not have in itself its own ultimate reason for being, and manifests the fundamental structure of reality: the distinction between God, subsistent being itself, and other beings placed by him in existence. God is the Creator, the free and transcendent source of all other beings. These receive from him, "with measure, number and weight" (Wis 11:20), existence according to a nature that defines them. Creatures are therefore the manifestation of a personal creative wisdom, of a founding Logos that expresses and manifests itself in them. "Every creature is a divine word, since it is spoken by God," writes St. Bonaventure.61

63. The Creator is not only the principle of creatures but also the transcendent end towards which they tend by their nature. Thus creatures are animated by a dynamism that carries them to realize themselves, each in its own way, in the union with God. This dynamism is transcendent, insofar as it proceeds from the eternal law, i.e., from the divine plan of providence that exists in the Spirit of the Creator.62 But it is also immanent, since it is not imposed on creatures from without, but is inscribed in their very nature. Purely material creatures realize spontaneously the law of their being, while spiritual creatures realize it in a personal manner. They interiorize the dynamisms that define them and freely orientate them towards their complete realization. They formulate them for themselves, as fundamental norms of their moral action – the natural law in its proper sense – and they endeavor to realize them freely. The natural law is therefore defined as a participation in the eternal law.63 It is mediated, on the one hand, by the inclinations of human nature, expressions of the Creative Wisdom, and, on the other hand, by the light of human reason which interprets them and which is itself a created participation in the light of divine intelligence. Ethics presents itself as a "participated theonomy".64

3.2. Nature, person, and freedom

64. The notion of nature is particularly complex and is not at all univocal. In philosophy, the Greek thought of physis played a key role. In it nature designates the principle of the specific ontological identity of a subject, i.e., its essence which is defined by an ensemble of stable intelligible characteristics. Such an essence takes the name of nature above all when it is understood as the internal principle of movement which orients the subject towards its realization. The notion of nature does not refer to a static datum, but signifies the real dynamic principle of the continuous development of the subject and of its specific activities. The notion of nature was formed above all to think about material and sensible reality, but it is not limited to such a "physical" sphere and is analogously applicable to spiritual reality.

65. The idea according to which beings possess a nature is imposed on the spirit when it wants to give an account of the immanent finality of beings and of the regularity which it perceives in their manner of acting and reacting.65 To consider beings as natures means to recognize their proper single consistency and to affirm that they are relatively autonomous centers in the order of being and of acting, and not simply illusions or temporary constructions of consciousness. These "natures" are not, however, ontological unities closed in themselves and simply juxtaposed, one to the other. They act, one upon the other, maintaining a complete rapport of causality among each other. In the spiritual order, persons weave intersubjective relations. The natures therefore form a net, and in the last analysis, an order, i.e., a series unified by reference to a principle.66

66. With Christianity, the physis of the ancients was rethought and integrated in a broader and more profound vision of reality. On the one hand, the God of Christian revelation is not a simple component of the universe, an element of the grand Totality of nature. On the contrary, he is the transcendent and free Creator of the universe. In fact the finite universe cannot be founded on itself, but points to the mystery of an infinite God, who out of love created it ex nihilo and remains freely able to intervene in the course of nature whenever he wills. On the other hand, the transcendent mystery of God reflects on the mystery of the human person as an image of God. The human person is capable of knowledge and of love; he is endowed with freedom, he is capable of entering into communion with others and he is called by God to a destiny that transcends the finality of physical nature. He is fulfilled in a free and gratuitous relation of love with God that is realized in history.

67. Through its insistence on freedom as the condition of a human response to the loving initiative of God, Christianity has contributed in a determining manner to give due place to the notion of person in philosophical discourse, and thus has had a decisive influence in ethical doctrine. Further, the theological exploration of the Christian mystery has brought a very significant deepening of the philosophical theme of the person. On the one hand, the notion of person serves to designate in their distinction the Father, the Son, and the Spirit in the infinite mystery of the single divine nature. On the other hand, the person is the point in which, with respect to the distinction and distance between the two natures, divine and human, the ontological unity of the Man-God, Jesus Christ, is placed. In the Christian theological tradition, the person presents two complementary aspects. On the one hand, according to the definition of Boethius, taken up by scholastic theology, the person is a "individual substance (subsisting) of a rational nature".67 It refers to the uniqueness of an ontological subject which, being of a spiritual nature, enjoys a dignity and an autonomy that is manifested in self-consciousness and in the free dominion over its action. On the other hand, the person is manifested in its capacity to enter into relation: it exercises its action in the order of intersubjectivity and of communion in love.

68. Person is not opposed to nature. On the contrary, nature and person are two notions that complete one another. On the one hand, every human person is a unique realization of human nature understood in a metaphysical sense. On the other hand, the human person, in the free choices with which he responds in all the concreteness of his "here and now" to his unique and transcendent vocation, accepts the orientations given by his nature. In fact nature posits the conditions of the exercise of freedom and indicates an orientation for the choices that the person should make. Examining the intelligibility of his nature, the person thus discovers the way to his own realization.

3.3. Nature, man and God: from harmony to conflict

69. The concept of natural law presupposes the idea that nature is for man the bearer of an ethical message and establishes an implicit moral norm which human reason actualizes. The vision of the world within which the doctrine of natural law developed and still finds its meaning today, involves therefore the reasoned conviction that there exists a harmony between the three substances which are God, man, and nature. In this perspective, the world was perceived as an intelligible whole, united by the common reference of the beings that compose it to a divine founding principle, to a Logos. Beyond the impersonal and immanent Logos seen by stoicism and presupposed by modern natural science, Christianity affirms that the Logos is personal, transcendent and creator. "It is not the elemental spirits of the universe, the laws of matter, which ultimately govern the world and mankind, but a personal God governs the stars, that is, the universe; it is not the laws of matter and of evolution that have the final say, but reason, will, love - a person".68 The personal divine Logos - Wisdom and Word of God – is not only the origin and the transcendent intelligible model of the universe, but also the one who maintains it in a harmonious unity and leads it to its end.69 With the dynamism which the creator Word has inscribed in the interior of beings, he orders them to their full realization. This dynamic orientation is none other than the divine government, which is the realization in time of the plan of divine providence, i.e., the eternal law.

70. Every creature participates in its own manner in the Logos. Man, since he is defined by reason or logos, participates in it in an eminent manner. By reason he is able to freely interiorize the divine intentions manifested in the nature of things. He formulates them under the form of a moral law that inspires and orders his own action. In this perspective, man is not "the other" in relation to nature. On the contrary, he establishes with the cosmos a bond of familiarity based on a common participation in the divine Logos.

71. For various historical and cultural reasons, which gather particularly in the evolution of ideas during the late Middle Ages, this vision of the world lost its cultural supremacy. The nature of things no longer makes law for modern man and is no longer a reference for ethics. On the metaphysical level, the substitution of the notion of the univocity of being in place of the notion of the analogy of being and then nominalism have threatened the foundations of the doctrine of creation as a participation in the Logos that explains a certain unity between man and nature. The nominalist universe of William of Ockham is thus reduced to a juxtaposition of individual realities without depth, inasmuch as every real universal, i.e., every principle of communion among beings, is denounced as a linguistic illusion. On the anthropological level, the development of voluntarism and the correlative exaltation of subjectivity, defining freedom as indifference to every natural inclination, have radically separated the human subject from nature. Now some people believe that human freedom means essentially the power to completely disregard nature. The subject should therefore reject any meaning in anything he has not personally chosen and should decide for himself what it is to be man. Man, therefore, has come more and more to understood himself as a "denatured animal," an anti-natural being that affirms itself to the degree that it opposes itself to nature. Culture, proper to man, is then defined not as a humanization or a transfiguration of nature by spirit, but as a pure and simple negation of nature. The principal result of such evolutions was the division of reality in three separate, even opposed spheres: nature, human subjectivity, and God.

72. With the eclipse of the metaphysics of being, alone capable of founding on reason the differentiated unity of spirit and of material reality, and with the growth of voluntarism, the kingdom of spirit was radically opposed to the kingdom of nature. Nature was no longer considered as an epiphany of the Logos, but as "the other" for the Spirit. It was reduced to the environment of the body and of strict necessity, and of a corporeality without depth, since the corporeal world was identified with extension, certainly regulated by intelligible mathematical laws, but deprived of any immanent teleology or finality. The Cartesian and then the Newtonian physics have spread the image of an inert matter, which passively obeys the laws of universal determinism that the Divine Spirit imposes on them and which the human reason can recognize and perfectly master.70 Only man can infuse a meaning and a design in this amorphous and insignificant mass that he manipulates with technology for his own ends. Nature ceases to be a lord of life and of wisdom, becoming the place in which the promethean potency of man affirms itself. This vision seemed to give value to human freedom, but in fact, by opposing freedom and nature, it deprived human freedom of any objective norm for its conduct.. It leads to the idea of an entirely arbitrary human creation, even a pure and simple nihilism.

73. In this context, in which nature no longer conceals any immanent teleological rationality and seems to have lost all affinity or kinship with the world of spirit, the passage from knowledge of the structures of being to moral duty which seems to derive from it became effectively impossible and fell under the criticism of "sophism or naturalistic fallacy," denounced by David Hume and then by George Edward Moore in his Principia Ethica (1903). In effect the good was disconnected from being and from truth. Ethics was separated from metaphysics.

74. The evolution of the comprehension of the rapport of man with nature is reflected also in the rebirth of a radical anthropological dualism which opposes spirit and body, inasmuch as the body is in a certain way the "nature" in each of us.71 Such dualism manifests itself in the refusal to recognize any human and ethical meaning in the natural inclinations that precede the choice of the individual reason. The body, judged a reality external to subjectivity, becomes a pure "possession," an object manipulated by technology in the service of the interests of the individual subjectivity.72

75. Further, through the emergence of a metaphysical conception in which human and divine action compete with one another, inasmuch as they are understood univocally and placed, wrongly, on the same level, the legitimate affirmation of the autonomy of the human subject implies that God is excluded from the sphere of human subjectivity. Every reference to something normative coming from God or from nature as an expression of God's wisdom, every "heteronomy," is perceived as a threat to the subject's autonomy. The notion of natural law then appears incompatible with the authentic dignity of the subject.

3.4. Ways towards a reconciliation

76. To give the whole meaning and weight to the notion of the natural law as foundation of a universal ethics, there is need to look at wisdom, the properly metaphysical order, capable of simultaneously embracing God, the cosmos and the human person, to reconcile them in the analogous unity of being, through the idea of creation as a participation.

77. It is above all essential to develop a non-competitive idea of the relationship between divine causality and the free activity of the human subject. The human subject realizes itself by inserting itself freely in the providential action of God, and not by opposing itself to this action. It should with its reason detect and accept the profound dynamisms that define its nature, and should lead them freely to their full realization. Human nature is defined by an ensemble of dynamisms, tendencies and internal orientations from which freedom arises. In fact freedom supposes that the human will is "placed under tension" by the natural desire fof good and for the last end. Free will is exercised then in the choice of the finite objects that allow one to attain this end. As regards these goods, which exercise an attraction that does not determine the will, the person retains mastery of his proper choice by reason of an innate openness to absolute good. Freedom is therefore not an absolute self-creator of itself, but an eminent property of every human subject.

78. A philosophy of nature that recognizes the intelligible depth of the sensible world, and above all, a metaphysics of creation enable one to overcome the dualistic and gnostic temptation to abandon nature to moral insignificance. From this point of view, we must overcome the reductive outlook on nature that the dominant technological culture tends to produce, in order to rediscover the moral message of which it is the bearer, as a work of the Logos.

79. The rehabilitation of nature and of corporeality in ethics cannot, however, be equated with any kind of "physicalism." In fact some modern presentations of natural law have seriously denied the necessary integration of natural inclinations in the unity of the person. Neglecting to consider the unity of the human person, they absolutize the natural inclinations of the different "parts" of human nature, approaching them without hierarchizing them, and failing to integrate them in the unity of the entire plan of the subject. Now, John Paul II explains, "natural inclinations do not acquire a moral quality, except insofar as they are connected to the human person and to his authentic realization".73 Today therefore there is need to hold fast to two truths. On the one hand, the human subject is not a union or juxtaposition of diverse and autonomous natural inclinations, but a substantial and personal whole called to respond to the love of God and to unite himself through a recognized orientation towards a last end, which hierarchizes the partial goods manifested by diverse natural tendencies. Such a unification of natural tendencies in service of the higher ends of the spirit, i.e., such a humanization of the dynamisms inscribed in human nature, does not at all constitute a violence done to it. On the contrary, it is the realization of a promise already inscribed in them.74 For example, the high spiritual value that is manifested in the gift of self in the reciprocal love of spouses is already inscribed in the very nature of the sexual body, which finds in this spiritual realization its ultimate reason for being. On the other hand, in this organic whole, each part preserves a proper and irreducible meaning, of which reason should take account in the elaboration of the entire plan of the human person. The doctrine of the natural moral law should therefore affirm the central role of reason in the actualization of a properly human plan of life, and at the same time the consistency and the proper meaning of natural pre-rational dynamisms.75

80. The moral significance of natural pre-rational dynamisms appears in full light in the teaching concerning sins against nature. Certainly, every sin is against nature insofar as it is opposed to right reason and hinders the authentic development of the human person. Nevertheless, some behaviors are considered especially sins against nature to the extent that they contradict more directly the objective sense of the natural dynamisms that the person should take up into the unity of his moral life.76 Thus deliberate and voluntary suicide goes against the natural inclination to preserve and to make fruitful one's own existence. Thus some sexual practices are directly opposed to the finality inscribed in the human sexual body. Hence they also contradict the interpersonal values that should promote a responsible and fully human sexual life.

81. The risk of absolutizing nature, reduced to purely physical or biological components, and of neglecting its proper inner vocation to be integrated into a spiritual plan, today threatens some radical tendencies of the ecological movement. The irresponsible exploitation of nature on the part of human agents who seek only economic profit and the dangers that this exploitation poses to the biosphere justly bear on our consciences. Nevertheless, "deep ecology" constitutes an excessive reaction. It upholds a supposed equality of living species, without being able to recognize any particular role for the human being, and thus, paradoxically, weakens the responsibility of man in regard to the biosphere of which he is part. In a still more radical manner, some were led to consider the human being as a destructive virus that threatened the integrity of nature, and denied it any meaning and any value in the biosphere. The result is a kind of totalitarianism that excludes human existence in its specificity and condemns legitimate human progress.

82. There cannot be an adequate response to the complex questions of ecology, if it is not within the picture of a more profound comprehension of the natural law, which gives value to the link between the human person, society, culture, and the equilibrium of the bio-physical sphere in which the human person is incarnate. An integral ecology should promote that which is specifically human, at the same time appreciating the value of the world of nature in its physical and biological integrity. In fact, even if man, as a moral being that searches for the truth and the ultimate goods, transcends his own immediate environment, he does it by accepting the special mission to keep watch over the natural world and to live in harmony with it, to defend the vital values without which neither human life nor the biosphere of this planet can be maintained.77 Such an integral ecology is a new responsibility which makes a call on every human being and every community. It is inseparable from a global orientation respectful of the requirements of the natural law.

Chapter four: natural law and the city

4.1. The person and the common good

83. Turning to the political order of society, we enter into the space regulated by law. In fact the law appears when several persons enter into relationship. The passage from person to society sheds light on the essential distinction between natural law and natural right.

84. The person is at the center of the political and social order because he is an end and not a means. The person is a social being by nature, not by choice or in virtue of a pure contractual convention. To flourish as a person he needs a network of relations established with other persons. One finds oneself thus at the center of a net formed by concentric circles: the family, the environment in which he lives and works, the local community, the nation, and finally humanity.78 The person draws from each of these circles the elements necessary for his own growth, and at the same time contributes to their improvement.

85. Since human beings have the vocation to live in society with others, they have in common an ensemble of goods to pursue and values to defend. This is what is called the "common good." If the person is an end in himself, the end of society is to promote, consolidate and develop its common good. The search for the common good allows the city to mobilize the energies of all its members. At a first level, the common good can be understood as the ensemble of conditions that allow a person to be always more a human person.79 While articulated in its external aspects—the economy, security, social justice, education, access to work, spiritual searching, etc.— the common good is always a human good.80 At a second level, the common good is that at which the political order and the city itself aims. The good of all and of each one in particular, it expresses the communitarian dimension of the human good. Societies can be defined by the type of common good they seek to promote. In fact if one considers the essential requirements of the common good of every society, the vision of the common good evolves with the same societies, in service of the conceptions of the person, justice, and the role of the public authority.

4.2. The natural law, measure of the political order

86. Society organized for the common good of its members corresponds to a requirement of the social nature of the person. The natural law appears then as the normative background in which the political order is called to move. It defines the ensemble of values that appear as humanizing for a society. When we place ourselves in the social and political environment, values can be no longer of a private, ideological or confessional nature, but regard all the citizens. They do not express a vague agreement between them, but are based on the requirements of their common humanity. So that society may fulfil correctly its own mission of serving the person, it should promote the realization of the person's natural inclinations. The person is therefore prior to society, and society is humanized only if it responds to the expectations inscribed in the person insofar as he is a social being.

87. Such a natural order of society in the service of the person is connoted, according to the social doctrine of the Church, by the four values that derive from the natural inclinations of the human being and which designate the contours of the common good that society should pursue; these are: freedom, truth, justice, and solidarity.81 These four values correspond to the requirements of an ethical order in conformity with the natural law. If one if these begins to be lacking, the city will tend towards anarchy or the rule of the strongest. Freedom is the first condition for a humanly acceptable political order. Without the liberty of following one's own conscience, expressing one's own opinions and pursuing one's own plans, there is not a human city, even if the search for private goods should always be articulated in a manner that promotes the common good of the city. Without the search and respect for truth, there is not a society but a dictatorship of the strongest. Truth, which is not the property of anyone, is able to bring all human beings together towards common objectives. If truth does not impose itself, the most skilful imposes "his" truth. Without justice there is no society, but the reign of violence. Justice is the highest good that the city can procure. It supposes that it always seeks what is just, and that law is applied with attention to the particular case, since equity is the highest part of justice. Finally, it is necessary for society to be regulated by solidarity, assuring reciprocal help and responsibility for the lot of others and acting in a manner such that the goods of which society disposes can answer to the needs of all.

4.3. From natural law to natural right

88. Natural law (lex naturalis) is expressed as natural right (ius naturale) when one considers the relations of justice between human beings: relations between physical and moral persons, between persons and the public authority, relations of all with the positive law. One passes from the anthropological category of the natural law to the juridical and political category of the organization of the city. Natural right is the inherent measure of the accord between the members of society. It is the rule and the immanent measure of interpersonal and social rapport.

89. Right is not arbitrary: the requirement of justice, which derives from natural law, is prior to every formulation and emancipation of right. It is not right which decides that something is just. Not even political law is arbitrary: the norms of justice do not result only from a contract established between men, but comes above all from the very nature of human beings. Natural right is the anchoring of human law to natural law. It is the background to which the human legislator should look as a guideline when he decrees norms in his mission of serving the common good. In this sense, it honors the natural law, inherent in man's humanity. On the contrary, when natural right is denied, the will alone of the legislator makes the law. Then the legislator is no longer the interpreter of that which is just and good, but attributes to himself the prerogative of being the ultimate criterion of what is just.

90. Natural right is never a measured fixed once for all. It is the result of an evaluation of the changing situations in which man lives. It enunciates the judgment of practical reason assessing what is just. Natural right, the juridical expression of the natural law in the political order, thus appears as the measure of the just relations between the members of the community.

4.4. Natural law and positive law

91. Positive law should endeavor to actualize the requirements of natural law. It does this either by way of conclusions (the natural law prohibits homicide, positive law prohibits abortion), or by way of determinations (natural law prescribes that the guilty be punished, positive penal law determines the punishments to be applied for each category of crime).82 Inasmuch as they truly derive from natural law and thus from the eternal law, positive human laws are binding in conscience. When the contrary holds true, they are not binding. "If the law is not just, it is not even a law".83 Positive laws also can, and should, change to remain faithful to their own vocation. In fact, on the one hand, there is a progress of human reason that, little by little, becomes more aware of what is more suitable for the good of the community, and on the other hand, the historical conditions of the life of society change (for better or for worse) and the laws should adapt to this.84 Thus the legislator should determine what is just in concrete historical situations.85

92. Natural rights are measures of human relationships prior to the will of the legislator. They are given so that men may live in society. Natural right is that which is naturally just, prior to any legal formulation. It is expressed particularly in the subjective rights of the person, such as the respect for one's own life, for personal integrity, religious liberty, freedom of thought, the right to found a family and to educate children according to one's convictions, the right to associate with others, to participate in the life of the community... These rights, to which contemporary thought attributes great importance, have their source not in the fluctuating desires of individuals, but in the very structure of human beings and in their humanizing relations. The rights of the human person emerge therefore from the just order that should reign in the relations between men. To acknowledge these natural rights of man means to acknowledge the objective order of human relations based on the natural law.

4.5. The political order is not an eschatological order

93. In the history of human society, the political order was often understood as the reflection of a transcendent and divine order. Thus the ancient cosmologies founded and justified political theologies in which the sovereign ensured the link between the cosmos and the human universe. They brought the human universe into the pre-established harmony of the world. With the appearance of biblical monotheism, the universe was understood as obedient to the laws which the Creator gave it. The order of cities was achieved when they respected the laws of God, laws furthermore inscribed in the hearts of men. For a long time, forms of theocracy were able to prevail in societies organized according to principles and values treated by their holy books. There was no distinction between the sphere of religious revelation and the sphere of the organization of the city. But the Bible desacralized human authority, even if various ages of theocratic osmosis, even in a Christian environment, have obscured the essential distinction between the political and the religious order. In this regard, one must carefully distinguish the situation of the first covenant, in which the divine law given by God was also the law of the people of Israel, and that of the new covenant, which introduces the distinction and the relative autonomy of the religious and political orders.

94. The biblical revelation invites humanity to consider that the order of creation is a universal order in which all humanity participates, and that this order is accessible to reason. When we speak of natural law, we speak of this order willed by God and apprehended by human nature. The Bible makes the distinction between the order of creation and the order of grace, to which faith in Christ gives access. Now, the civil order is not this definitive and eschatological order. The political environment is not that of the heavenly city, gratuitous gift of God. It derives from the imperfect and transitory order in which men live, also advancing towards their realization on the other side of history. According to St. Augustine, it is proper to the earthly city to be intermingled: just and unjust are there placed side by side, believers and unbelievers.86 They must simultaneously live together according to the requirements of their nature and the capacity of their reason.

95. The State cannot therefore raise itself as the bearer of ultimate meaning. It cannot impose a global ideology, nor a religion (even secular), nor a single idea. The environment of ultimate meaning, in the civil society, is taken up by religious organizations, by philosophies or spiritualities; they should contribute to the common good, strengthen the social bond and promote the universal values that found the political order itself. This order does not have the task of bringing on earth the kingdom of God that shall come. It can anticipate it with its progress in the environment of justice, solidarity, and peace. It cannot establish it by force.

4.6. The political order is a temporal and rational order

96. Though the political order is not the sphere of the ultimate truth, it should still be open to the continual search for God, truth, and justice. The "legitimate and sound secularity of the State"87 consists of the distinction between the supernatural order of theological faith and the political order. This latter order can never be confused with the order of grace to which all men are called to freely adhere. It is, rather, bound to the universal human ethics inscribed in human nature. The city should thus procure for the people who compose it what is necessary for the full realization of their human life, which includes some spiritual and religious values, as well as the freedom for the citizens to decide about the Absolute and the supreme goods. But the city, whose good is of a temporal nature, cannot procure supernatural goods, which are of another order.

97. If God and every transcendence were to be excluded from the political horizon, nothing would remain but the authority of man over man. In fact the political order has often been presented as the last horizon of meaning for humanity. Totalitarian ideologies and regimes have demonstrated that such a political order, without a horizon of transcendence, is not humanly acceptable. This transcendence is connected to that which we call natural law.

98. The political-religious osmosis of the past, such as the totalitarian experiences of the 20th century, have led, thanks to a sound reaction, to a reevaluation today of the role of reason in politics, thus conferring a new relevance to the Aristotelian-Thomistic discourses on natural law. Politics, i.e., the civil organizations and the elaboration of their collective plans, derives from the natural order and should carry out a rational debate open to transcendence.

99. The natural law that is based on the social and political order needs an adhesion not of faith but of reason. Certainly reason itself has often been obscured by passions, by contradictory interests, by prejudices. But constant reference to natural law impels one to the continuous purification of reason. Only thus can the political order avoid the threat of the arbitrary, of particular interests, of organized untruth, of manipulation of spirits. The reference to natural law keeps the State from yielding to the temptation to absorb civil society and to subject men to an ideology. It also keeps a State from becoming a providence that deprives persons and communities of every initiative and takes responsibility away from them. Natural law contains the idea of the State of rights, which is structured according to the principle of subsidiarity, respecting persons and intermediate bodies and regulating their interactions.88

100. The great political myths have been unmasked with the introduction of the rule of rationality and the acknowledgment of the transcendence of the God of love who forbids the worship of the political order established on earth. The God of the Bible willed the order of creation so that all men, conforming themselves to the law that is inherent in them, can seek freely, and having found it, set in the world the light of grace and its fulfillment.

Chapter five:
Jesus Christ, fulfilment of the natural law

101. Grace does not destroy nature but heals it, strengthens it, and leads it to its full realization. For this reason, even if the natural law is an expression of reason common to all men and can be presented in a coherent and true manner on the philosophical level, it is not external to the order of grace. Its claims are present and operating in the different theological states through which our one humanity has passed in the history of salvation.

102. The plan of salvation which the eternal Father has initiated is realized with the mission of the Son who gives man a new Law, the law of the Gospel, which consists principally in the grace of the Holy Spirit working in the hearts of believers to sanctify them. The new law aims above all to procure for man the participation in the trinitarian communion of the divine persons, but at the same time takes up and realizes the natural law in an eminent manner. On the one hand, it recalls clearly the requirements that can be obscured by sin or by ignorance. On the other hand, freeing him from the law of sin, which cause one to "have the desire for good, but not the ability to do it" (Rom 7:18), it gives man the effective capability of overcoming egoism by fully actualizing the humanizing demands of the natural law.

5.1. The incarnate Logos, living Law

103. Through the natural light of reason, which is a participation in the divine light, men are able to examine the intelligible order of the universe in order to discover the expression of the wisdom, beauty and goodness of the Creator. On the basis of this knowledge, they can insert themselves into this order with their moral action. Now, thanks to a deeper look at God's plan, of which the creative act is the prelude, Scripture teaches believers that this world was created in, by, and for the Logos, the Word of God, the beloved Son of the Father, uncreated Wisdom, and that the world has life and subsistence in him. In fact the Son is the "image of the invisible God, the first-born of all creation; for in him (en auto) all things were created, in heaven and on earth, visible and invisible [...] All things were created through him (di'auton) and for him (eis auton). He is before all things, and in him (en auto) all things hold together" (Col 1:15-17).89 The Logos is therefore the key of the creation. Man, created in the image of God, bears in himself a special imprint of this personal Logos. For man is called to be conformed and assimilated to the Son, "the first-born among many brethren" (Rom 8:29).

104. But on account of sin man has made bad use of his freedom and has removed himself from the source of wisdom. Thus acting, he has falsified the knowledge that he was able to have of the objective order of things, even on the natural level. Men, knowing that their works are bad, hate the light and elaborate false theories to justify their sins.90 Thus the image of God in man has been gravely obscured. Although their nature still refers them to a fulfilment in God beyond themselves (the creature cannot pervert itself to the point of not recognizing any longer the testimonies that the Creator offers of himself in the creation), in fact men are so gravely harmed by sin that they do not recognize the profound meaning of the world and interpret it in terms of pleasure, money or power.

105. By his saving incarnation, the Logos, assuming a human nature, restored the image of God and gave man back to himself. Thus Jesus Christ, the new Adam, bears fully the original plan of the Father for man and thus reveals man to himself: "The truth is that only in the mystery of the incarnate Word does the mystery of man find true light. For Adam, the first man, was a figure of him Who was to come, namely Christ the Lord. Christ, who is the new Adam, by the revelation of the mystery of the Father and his love, fully reveals man to man himself and makes his supreme calling clear. [...] 'He is the image of the invisible God' (Col. 1:15). He is the perfect man, who has restored to the sons of Adam the divine likeness which had been disfigured from the first sin onward. Since human nature as he assumed it was not annulled, by that very fact it has been raised up to a sublime dignity in us too".91 Jesus Christ manifests in his own person, therefore, an exemplary human life, fully conforming to the natural law. For that reason he is the ultimate criterion for correctly deciphering the authentic natural desires of man when they are not concealed by distortions introduced by sin and disordered passions.

106. The Incarnation of the Son was prepared by the economy of the old Law, a sign of God's love for his people Israel. According to some Fathers, one of the motives for which God gave Moses a written law was to remind man of the requirements of the law written by nature on their hearts but partially obscured and erased by sin.92 This law, which Judaism identified with the pre-existent wisdom that presides over the destiny of the universe,93 thus placed within the reach of men marked by sin the concrete practice of the true wisdom, which consists in the love of God and neighbour. It contained positive liturgical and juridical precepts but also moral prescriptions, summarized in the Decalogue, which corresponded to the implications of the natural law. Thus the Christian tradition saw in the Decalogue a privileged and always valid expression of the natural law.94

107. Jesus Christ did not "come to abolish the law but to fulfil" the law (Mt 5:17).95 As appears from the gospel texts, Jesus "taught as one having authority and not as the scribes" (Mk 1:22) and did not hesitate to relativize, or even to abolish, certain particular and temporary dispositions of the Law. But he also confirmed the essential content and, in his person, carried the practice of the law to perfection, taking up by love the different types of precepts – moral, cultural and judicial – of the mosaic Law, which correspond to the three functions of prophet, priest, and king. St. Paul affirms that Christ is the end (telos) of the law (Rom 10:4). Telos has here a twofold sense. Christ is the "end" of the law, in the sense that the law is a pedagogical means that was to lead men to Christ. But further, for all those who by faith live in him through the Spirit of love, Christ "puts an end" to the positive obligations of the law added to the requirements of the natural law.96

108. In fact Jesus expressed in different ways the value of the ethical primacy of charity, which unites inseparably the love of God and the love of neighbour.97 Charity is the "new commandment" (Jn 13:34) which recapitulates the whole law and gives it the key of interpretation: "On these two commandments depend all the law and the prophets" (Mt 22:40). It also reveals the profound meaning of the golden rule. "Do not do to anyone what you do not want done to you" (Tob 4:15) becomes with Christ the commandment to love without limit. The context in which Jesus cites the golden rule determines deeply its understanding. It is found at the center of a section that begins with the commandment: "Love your enemies, do good to those who hate you" and culminates with the exhortation "Be merciful as your heavenly Father is merciful".98 Beyond a rule of commutative justice, it has the form of a challenge: it invites one to take the initiative in a self-giving love. The parable of the Good Samaritan is characteristic of this Christian application of the golden rule: the center of interest passes from care for oneself to care for the other.99 The beatitudes and the Sermon on the Mount illustrate the manner in which one should live the commandment of love, in gratitude and respect for others, proper elements of the new perspective taken up by Christian love. Thus the practice of love overcomes every closure and every limit. It acquires a universal dimension and an unmatchable strength, because it renders the person capable of doing that which is impossible without love.

109. But above all in the mystery of his passion Jesus carries the law of love to its fulfillment. Here, as incarnate Love, he reveals in a fully human manner what love is and what it implies: to give one's love for those whom one loves.100 "Having loved his own who were in the world, he loved them to the end" (Jn 13,1). Through obedience to and love for the Father and through the desire of his glory which consists in the salvation of men, Jesus accepted the suffering and death of the cross for the sake of sinners. The very person of Christ, incarnate Logos and Wisdom, thus became the living law, the supreme norm for all Christian ethics. The sequela Christi, the imitatio Christi are the concrete ways to fulfill the law in all its dimensions.

5.2. The Holy Spirit and the new law of freedom

110. Jesus Christ is not only an ethical model to imitate, but with and in his paschal mystery, he is the Savior who gives every man the real possibility of putting into action the law of love. In fact the paschal mystery culminates in the gift of the Holy Spirit, the Spirit of love common to the Father and the Son, who unites the disciples among themselves, to Christ and finally to the Father. "Because God's love has been poured into our hearts through the Holy Spirit" (Rom 5:5), the Holy Spirit becomes the interior principle and the supreme rule of the action of believers. It makes them accomplish spontaneously and in a just manner all the requirements of love. "Walk by the Spirit, and do not gratify the desires of the flesh" (Gal 5:16). Thus is fulfilled the promise: "A new heart I will give you, and a new spirit I will put within you; and I will take out of your flesh the heart of stone and give you a heart of flesh. And I will put my spirit within you, and cause you to walk in my statutes and be careful to observe my ordinances" (Ezek 36:26-27).101

111. The grace of the Holy Spirit constitutes the principal element of the new law, or law of the Gospel.102 The preaching of the Church, the celebration of the sacraments, the dispositions taken by the Church to favor among her members the development of the life in the Spirit are totally referred to the personal growth of every believer in the holiness of love. With the new law, which is an essentially interior law, "the perfect law, the law of freedom" (Jam 1:25), the desire for autonomy and freedom in the truth that is present in the human heart finds its most perfect realization. From the innermost center of the person, indwelt by Christ and transformed by the Spirit, his moral action is born.103 But this freedom is for the service of love: "You were called to freedom, brethren; only do not use your freedom as an opportunity for the flesh, but through love be servants of one another" (Gal 5:13).

112. The new Law of the Gospel includes, takes up and brings to fulfillment the requirements of the natural law. The orientations of the natural law are not therefore external normative demands with respect to the new Law. They are a constitutive part of it, even if secondary and ordered to the principal element, which is the grace of Christ.104 Therefore it is in the light of reason enlightened by living faith that man recognizes better the orientations of the natural law, which indicate to him the way to the full development of his humanity. Thus the natural law, on the one hand, remains "a fundamental link with the new law of the Spirit of life in Christ Jesus, and on the other hand, offers a wider base for dialogue with persons of another orientation or of another formation, in view of the search for the common good".105


113. The Catholic Church, aware of the necessity for man to seek in common the rules for living together in justice and peace, desires to share with the religions, wisdom traditions and philosophies of our time the resources of the concept of natural law. We call natural law the foundation of a universal ethics which we seek to derive from the observation of and reflection on our common human nature. It is the moral law inscribed in the heart of men and of which humanity should always become more aware as it advances in history. This natural law is not at all static in its expression; it does not consist in a list of definitive and immutable precepts. It is a source of inspiration that always springs up in the search for an objective foundation for a universal ethics.

114. Our conviction of faith is that Christ reveals the fullness of what is human by realizing it is in his person. But this revelation, inasmuch as it specifies elements already present in the rational thought of the wisdom traditions of humanity, takes up and confirms them. The concept of natural law is therefore above all philosophical, and as such, allows a dialogue that, with respect for the religious convictions of each, appeals to what is universally human in every human being. An exchange on the level of reason is possible when it is a matter of experience and of saying what is common to all men endowed with reason and of establishing the requirements of life in society.

115. The detection of the natural law answers to the search of a humanity that always endeavors to give itself rules for moral life and life in society. This life in society regards an arc of relations that reach from the nuclear family to international relations, passing through economic life, civil society, and the political community. To be able to be recognized by all men and in all cultures, the norms of behavior in society should have their source in the human person himself, in his needs, in his inclinations. These norms, elaborated with reflection and upheld by law, can thus be interiorized by all. Since the second world war, nations of all the world have been able to make a universal declaration of human rights, which implicitly suggests that the source of inalienable human rights is found in the dignity of every human person. The present contribution has no other aim than helping to reflect on this source of personal and collective morality.

116. Offering our contribution to the search for a universal ethics, and proposing a rationally justifiable foundation, we desire to invite experts and the spokespersons of the great religious, sapiential and philosophical traditions of humanity to proceed to an analogous work, beginning from their sources, to reach a common recognition of the universal moral norms based on a rational approach to reality. This work is necessary and urgent. We should reach the point of saying, behind our religious convictions and the diversity of our cultural presuppositions, what are the fundamental values for our common humanity, in a manner to work together to promote comprehension, reciprocal recognition and peaceful cooperation between all the members of the human family.


* PRELIMINARY NOTE. The theme "The search for universal ethics: a new look at natural law" was submitted to the study of the International Theological Commission. To prepare this study a Subcommittee was formed, composed of Msgr. Roland Minnerath, the Reverend Professors: P. Serge-Thomas Bonino OP (Chairman of the Subcommittee), Geraldo Luis Borges Hackmann, Pierre Gaudette, Tony Kelly CssR, Jean Liesen, John Michael McDermott SJ, of professors Dr. Johannes Reiter and Dr. Barbara Hallensleben, with the collaboration of Mgsr. Luis Ladaria SJ, Secretary General, and with the contributions of other members. The general discussion was held during the plenary sessions of the ITC, which took place in Rome in October 2006 and 2007 and in December 2008. The document was approved unanimously by the Commission in its session of December 1-6, 2008 and was then submitted to its president, Cardinal William J. Levada, who has given his approval for publication.

1. Vatican Council II, Pastoral constitution Gaudium et spes, preface, n. 1.

2. Cf. Ez 36:26.

3. John Paul II, Speech to the General Assembly of the United Nations for the celebration of the 50th anniversary of its founding, October 5, 1995, in Insegnamenti di Giovanni Paolo II, XVIII/2, 1995, Città del Vaticano, 1998, 732.

4. Cf. Benedict XVI, Address of the Holy Father to the General Assembly of the United Nations Organization in New York (April 18, 2008) in AAS 100 (2008) 335: "The merit of the Universal Declaration is that it has enabled different cultures, juridical expressions and institutional models to converge around a fundamental nucleus of values, and hence of rights. Today, though, efforts need to be redoubled in the face of pressure to reinterpret the foundations of the Declaration and to compromise its inner unity so as to facilitate a move away from the protection of human dignity towards the satisfaction of simple interests, often particular interests. [...] Experience shows that legality often prevails over justice when the insistence upon rights makes them appear as the exclusive result of legislative enactments or normative decisions taken by the various agencies of those in power. When presented purely in terms of legality, rights risk becoming weak propositions divorced from the ethical and rational dimension which is their foundation and their goal. The Universal Declaration, rather, has reinforced the conviction that respect for human rights is principally rooted in unchanging justice, on which the binding force of international proclamations is also based. This aspect is often overlooked when the attempt is made to deprive rights of their true function in the name of a narrowly utilitarian perspective."

5. In 1993, some representatives of the Parliament of the World's Religions made public a Towards a Global Ethic: An Initial Declaration, which affirms that "there already exists among religions a consent capable of founding a global ethic, a minimum consent that regards binding values, irrevocable norms, and essential moral inclinations." This Declaration contains four principles. (1) "No new global order without a new global ethic." (2) "Every human being must be treated humanely." The worth in consideration of human dignity is considered as an end in itself. This principle takes up the "golden rule" that is present in many religious traditions. (3) The Declaration enunciates four irrevocable moral directives: non-violence and respect for life; solidarity; tolerance and truthfulness; equality between men and women. (4) Regarding the problems of humanity, a change of mentality is necessary, so that each one is conscious of his urgent responsibility. It is a duty of the religions to cultivate this responsibility, to deepen it, and to hand it on to future generations.

6. Benedict XVI, To the participants in the International Congress on Natural Moral Law sponsored by the Pontifical Lateran University (February 12, 2007), in AAS 99 (2007) 244.

7. Cf. St. Augustine, De doctrina christiana, bk. 3, ch. 14, n. 22 (Corpus christianorum, series latina, 32, 91): "The precept: "what you do not want done to yourself, do not do to another" cannot in any way differ by reason of the difference of peoples (“Quod tibi fieri non vis, alii ne feceris”, nullo modo posse ulla eorum gentili diversitate variari)". Cf. L. J. Philippidis, Die «Goldene Regel» religionsgeschichtlich Untersucht, Leipzig, 1929; A. Dihle, Die Goldene Regel. Eine Einführung in die Geschichte der antiken und frühchristlichen Vulgarethik, Göttingen, 1962;J. Wattles, The Golden Rule, New York - Oxford, 1996.

8. Mānava dharmaśāstra, 1, 108 (G. C. Haughton, Mānava Dharma Śāstra or The Institutes of Manu, Comprising the Indian System of Duties, Religious and Civil, ed. P. Percival, New Delhi, 1982(4), 14.

9. Mahābhārata, Anusasana parva, 113, 3-9 (ed. Ishwar Chundra Sharma e O. N. Bimali; transl. according to M. N. Dutt, vol. IX, Delhi, Parimal Publications, 469).

10. For example: "Let him say what is true, let him say what is pleasing, let him utter no disagreeable truth, and let him utter no agreeable falsehood; that is the eternal law." (Mānava dharmaśāstra, 4, 138, p. 101); " Doing bodily injury, reviling, and the seizure of property, these three he must know to be the most pernicious in the set produced by wrath." (Mānava dharmaśāstra, 7, 51, p. 156).

11. Confucius, Entretiens 15, 23 (tr. A. Cheng, Paris, 1981, 125).

12. Koran, sura 35, 24; cf. sura 13, 7.

13. Koran, sura 17, 22-38 (tr. N. J. Dawood, Penguin Books, 2000, 283-284): "Your Lord has enjoined you to worship none but Him, and to show kindness to your parents. If either or both of them attain old age in your dwelling, show them no sign of impatience, nor rebuke them; but speak to them kind words. Treat them with humility and tenderness and say: 'Lord, be merciful to them. They nursed me when I was an infant.' Your Lord best knows what is in your hearts; He knows if you are good. He will surely forgive those that turn to Him. Give to the near of kin their due, and also to the destitute and to the traveller in need. Do not squander your substance wastefully, for the wasteful are Satan's brothers; and Satan is ever ungrateful to his Lord. But if, while waiting for your Lord's bounty, you lack the means to assist them, then at least speak to them kindly. Be neither miserly nor prodigal, for then you should either earn reproach or be reduced to penury. Your Lord gives abundantly to whom He will and sparingly to whom He pleases. He knows and observes His servants. You shall not kill your children for fear of want. We will provide for them and for you. To kill them is a grievous sin. You shall not commit adultery, for it is lewd and evil. You shall not kill any man whom God has forbidden you to kill, except for a just cause. . . . If a man is slain unjustly, his heir shall be entitled to satisfaction. But let him not carry his vengeance to excess, for his victim is sure to be assisted and avenged. Do not approach the property of orphans except with the best of motives, until they reach maturity. Keep your promises; your are accountable for all that you promise. Give full measure, when you measure, and weigh with even scales. That is better and fairer in the end. Do not follow what you know not. Man's eye's, ears, and hear – each of his senses shall be closely questioned. Do not walk proudly on the earth. You cannot split the earth, nor can you rival the mountains in stature. Evil is all this in the sight of your Lord, and odious."

14. Sophocles, Antigone, v. 449-460.

15. Cf. Aristotle, Rhetoric, I, XIII, 2 (1373 b 4-11): "Particular law is that which each community lays down and applies to its own members: this is partly written and partly unwritten. Universal law( nomos koinos) is that which is according to nature (kata physin). For there really is, as everyone to some extent divines, a natural justice and injustice that is common to all, even to those who have no association or covenant with each other. It is this that Sophocles' Antigone clearly means when she says that the burial of Polyneices was a just act in spite of the prohibition: she means that it was just by nature. Cf. also Nichomachean Ethics V, ch. 10.

16. Cf. Plato, Gorgias (483 c-484 b) [Speech of Callicles]: "nature herself intimates that it is just for the better to have more than the worse, the more powerful than the weaker; and in many ways she shows, among men as well as among animals, and indeed among whole cities and races, that justice consists in the superior ruling over and having more than the inferior. For on what principle of justice did Xerxes invade Hellas, or his father the Scythians? (not to speak of numberless other examples). Nay, but these are the men who act according to nature; yes, by Heaven, and according to the law of nature: not, perhaps, according to that artificial law, which we invent and impose upon our fellows, of whom we take the best and strongest from their youth upwards, and tame them like young lions, -charming them with the sound of the voice, and saying to them, that with equality they must be content, and that the equal is the honourable and the just. But if there were a man who had sufficient force, he would shake off and break through, and escape from all this; he would trample under foot all our formulas and spells and charms, and all our laws which are against nature: the slave would rise in rebellion and be lord over us, and the light of natural justice would shine forth."

17. In the Theatetus (172 a-b), Plato's Socrates explains the fateful political consequences of the relativist thesis attributed to Protagoras, according to which every man is the measure of the truth: "Again, in politics, while affirming that just and unjust, honourable and disgraceful, holy and unholy, are in reality to each state such as the state thinks and makes lawful, and that in determining these matters no individual or state is wiser than another [...] I mean when they speak of justice and injustice, piety and impiety, they are confident that in nature these have no existence or essence of their own - the truth is that which is agreed on at the time of the agreement, and as long as the agreement lasts."

18. Cf., for example, De vita beata, VIII, 1: "Nature must be followed as guide; reason observes and advises this. Therefore to live blessedly and to live according to nature are the same (Natura enim duce utendum est: hanc ratio observat, hanc consulit. Idem est ergo beate vivere et secundum naturam)".

19. Cicero, De legibus, I, VI, 18: "Lex est ratio summa insita in natura quae iubet ea quae facienda sunt prohibetque contraria".

20. Cf. Amos 1-2.

21. Rabbinic Judaism reports seven moral imperatives that God gave Noah for all men. They are enumerated in the Talmud (Sanhedrin 56): (1) You shall not make idols. (2) You shall not kill. (3) You shall not steal. (4) You shall not commit adultery. (5) You shall not blaspheme. (6) You shall not eat the flesh of a living animal. (7) You shall establish tribunals of justice to respect the six preceding commandments. While the 613 mitzot of the written Torah and their interpretation in the oral Torah concern only the Jews, the laws of Noah are addressed to all men.

22. The wisdom literature is interested in history above all inasmuch as it makes certain constants evident in regard to the way that leads man to God. The wise men did not scorn the lessons of history and their value of divine revelation (cf. Sir 44-51), but they have a living consciousness of the link between the events dependent on a coherence that is not a historical event. To understand this identity within mutability and to act in a responsible manner by reason of this, wisdom seeks the structural principles and the laws rather than the precise historical perspectives. Doing this, the wisdom literature concentrates on protology, i.e., the initial creation, with what it implies. In fact protology tries to describe the coherence that is found behind historical events. It is an a priori condition that allows one to set in order all the possible historical events. The wisdom literature seeks therefore to appreciate the conditions that make everyday life possible. History describes these elements in a successive manner, wisdom goes beyond history towards an atemporal description of that which constitutes reality at the time of creation, "in the beginning," when human beings were created unto the image of God.

23. Cf. Prov 6,6-9: "Go to the ant, O sluggard; consider her ways, and be wise. Without having any chief, officer or ruler, she prepares her food in summer, and gathers her sustenance in harvest. How long will you lie there, O sluggard? When will you arise from your sleep?"

24. Cf. also Lk 6,31: "And as you wish that men would do to you, do so to them."

25. Translation from the French edition of the Bible. Cf. St. Bonaventure, Commentarius in Evangelium Lucae, c. 6, n. 76 («Opera omnia, VII», ed. Quaracchi, p. 156): "In hoc mandato [Lc 6,31] est consummatio legis naturalis, cuius una pars negativa ponitur Tobiae quarto et implicatur hic: “Quod ab alio oderis tibi fieri, vide ne tu aliquando alteri facias”"; (Pseudo-)Bonaventura, Expositio in Psalterium, Ps 57,2 («Opera omnia, IX», ed. Vivès, p. 227); "Duo sunt mandata naturalia: unum prohibitivum, unde hoc “Quod tibi non vis fieri, alteri ne feceris”; aliud affirmativum, unde in Evangelio “Omnia quaecumque vultis ut faciant vobis homines, eadem facite illis”. Primum de malis removendis, secundum de bonis adipiscendis".

26. Cf. Vatican Council I, Dogmatic Constitution Dei Filius, c. 2. Cf. also Acts 14,16-17: "In past generations he allowed all the nations to walk in their own ways; yet he did not leave himself without witness, for he did good and gave you from heaven rains and fruitful seasons, satisfying your hearts with food and gladness."

27. In Philo of Alexandria is found the idea according to which Abraham, without the written Law, already "by nature" led a life in conformity with the Law. Cf. Philo of Alexandria, De Abrahamo, § 275-276 (Introduzione, traduzione e note di J. Gorez, "Les œuvres de Philon d’Alexandrie, 20", Paris, 1966, 132-135): "Moses says: This man (Abraham) observed the divine law and all the divine ordinances (Gen 26:5). And he had not received a teaching of written texts. But, urged by nature – not written – he puts his zeal into following action sound and without defect."

28. Cf. Rom 7,22-23: "I delight in the law of God, in my inmost self, but I see in my members another law at war with the law of my mind and making me captive to the law of sin which dwells in my members."

29. Clement of Alexandria, Stromata, I, c. 29, 182, 1 ["Sources chrétiennes", 30, p. 176].

30. St. Augustine, Contra Faustum, XXII, c. 27 [PL 42, col. 418]: "Lex vero aeterna est ratio divina vel voluntas Dei, ordinem naturalem conservari iubens, perturbari vetans". For example, St. Augustine condemns lying, because it is directly against the nature of language and its calling to be a sign of one's thought; cf. Enchiridion, VII, 22 [Corpus christianorum, series latina, 46, 62]: "speech was not formed in order for men to mutually deceive each another, but in order for them to make others aware of their thoughts. To make use of speech to deceive and not for the end for which it was formed is therefore a sin (Et utique verba propterea sunt instituta non per quae invicem se homines fallant sed per quae in alterius quisque notitiam cogitationes suas perferat. Verbis ergo uti ad fallaciam, non ad quod instituta sunt, peccatum est)".

31. St. Augustine, De Trinitate, XIV, XV, 21 [Corpus christianorum, series latina, 50 A, 451]: "Where are these rules written? Where may even an unjust man know what is just? Where may he see that he has need of that which he has not? Where are they written, if not in the book of that light which is called Truth, by which every just law is written and transferred,not by moving but by being impressed, into the heart of the man who does justice, as an image passes from a ring into wax without leaving the ring? (Ubinam sunt istae regulae scriptae, ubi quid sit iustum et iniustus agnoscit, ubi cernit habendum esse quod ipse non habet? Ubi ergo scriptae sunt, nisi in libro lucis illius quae veritas dicitur, unde omnis lex iusta describitur et in cor hominis qui operatur iustitiam non migrando sed tamquam imprimendo transfertur, sicut imago ex anulo et in ceram transit et anulum non relinquit?)".

32. Cf. Gaius, Instituta, 1. 1 (II sec. d.C.) (ed. J. Reinach, "Collection des universités de France", Paris, 1950, 1): "Quod vero naturalis ratio inter omnes homines constituit, id apud omnes populos peraeque custoditur vocaturque ius gentium, quasi quo iure omnes gentes utuntur. Populus itaque romanus partim suo proprio, partim communi omnium hominum iure utitur".

33. Saint Thomas Aquinas distinguishes clearly the natural political order, based on reason, from the supernatural religious order, based on the grace of revelation. He opposes the Muslim philosophers and Medieval Jews who attributed to religious revelation an essentially political role. Cf. Quaestiones disputatae de veritate, q. 12, a. 3, ad 11: "The society of men inasmuch as it is ordered to eternal life as an end, can only be preserved by the righteousness of faith, the principle of which is prophecy [...] But since this end is supernatural, so also the righteousness ordered to this end, and prophecy, which is its principle, will be supernatural. But the justice by which human society is governed with respect to the civil good, can be sufficiently had through the principles of natural law innate in man. (Societas hominum secundum quod ordinatur ad finem vitae aeternae, non potest conservari nisi per iustitiam fidei, cuius principium est prophetia [...] Sed cum hic finis sit supernaturalis, et iustitia ad hunc finem ordinata, et prophetia, quae est eius principium, erit supernaturalis. Iustitia vero per quam gubernatur societas humana in ordine ad bonum civile, sufficienter potest haberi per principia iuris naturalis homini indita)".

34. Cf. Benedict XVI, Discourse at Regensburg at the meeting with the representatives of the world of science (September 12, 2006), in AAS 98 (2006) 733: "In the late Middle Ages we find trends in theology which would sunder this synthesis between the Greek spirit and the Christian spirit. In contrast with the so-called intellectualism of Augustine and Thomas, there arose with Duns Scotus a voluntarism which, in its later developments, led to the claim that we can only know God's voluntas ordinata. Beyond this is the realm of God's freedom, in virtue of which he could have done the opposite of everything he has actually done. This gives rise to positions which [...] might even lead to the image of a capricious God, who is not even bound to truth and goodness. God's transcendence and otherness are so exalted that our reason, our sense of the true and good, are no longer an authentic mirror of God, whose deepest possibilities remain eternally unattainable and hidden behind his actual decisions."

35. Thomas Hobbes, Leviathan, Part II, c. 26, "The interpretation of the laws of nature in a Commonwealth dependeth not on the books of moral philosophy. The authority of writers, without the authority of the Commonwealth, maketh not their opinions law, be they never so true."

36. The position of the Reformers as regards the natural law was not monolithic. More than Martin Luther, John Calvin, basing himself on St. Paul, recognizes the existence of the natural law as ethical norm, even if it is radically incapable of justifying man. "Nothing, indeed, is more common, than for man to be sufficiently instructed in a right course of conduct by natural law, of which the Apostle here speaks [...]. The end of the natural law, therefore, is to render man inexcusable, and may be not improperly defined as: the judgment of conscience distinguishing sufficiently between just and unjust, and by convicting men on their own testimony, depriving them of all pretext for ignorance." In the three ages following the Reformation, for the Protestants the natural law served as the foundation for jurisprudence. Only with the secularization of the natural law, in the 19th century, has Protestant theology distanced itself from it. Only from this period has there been opposition between Catholic and Protestant opinion on the question of the natural law. But today the Protestant ethic seems to manifest a new interest in this notion.

37. The expression originates with Hugh Grotius, De iure belli et pacis, Prolegomena: "The things we have just said would have a place, even if we granted, which one may not do without the greatest iniquity, that God did not exist."

38. Gratian, Concordantia discordantium canonum, pars I, dist. 1 [PL 187, col. 29]: "The human race is ruled by two things, namely by natural law and by custom. Natural law is that which is contained in the law and in the Gospel, by which everyone is commanded to do to others what he wants done to him, and is forbidden from inflicting on others what he does not want done to him. [...] All laws are either divine or human. The divine are based on nature, the human on custom – the latter differ, because different things please different nations."

39. Cf. Paul VI, Encyclical Humanae vitae, n. 4, in AAS 60 (1968) 483.

40. Cf. Catechism of the Catholic Church, nn. 1954-1960; John Paul II, Encyclical Veritatis splendor, nn. 40-53.

41. Benedict XVI, To the participants in the International Congress on Natural Moral Law sponsored by the Pontifical Lateran University (February 12, 2007), in AAS 99 (2007) 243.

42. Cf. Benedict XVI,Address to the General Assembly of the United Nations Organization in New York (April 18, 2008) in AAS 100 (2008) 335: "These rights [human rights] are based on the natural law inscribed on human hearts and present in different cultures and civilizations. Removing human rights from this context would mean restricting their range and yielding to a relativistic conception, according to which the meaning and interpretation of rights could vary and their universality would be denied in the name of different cultural, political, social and even religious outlooks."

43. Cf. John Paul II, Encyclical Evangelium vitae, nn. 73-74.

44. Cf. John Paul II., Encyclical Veritatis splendor, n. 44: "The Church has often made reference to the Thomistic doctrine of natural law, including it in her own teaching on morality."

45. St. Thomas Aquinas, Summa theologiae, Ia-IIae, q. 94, a. 2: "The first precept of the law is that good is to be done and pursued, and evil is to be avoided. And all other precepts of the natural law are based on this one: thus whatever practical reason naturally apprehends as human goods [or evils], pertain to the precepts of the natural law as things to be done or to be avoided. (Hoc est primum praeceptum legis, quod bonum est faciendum et prosequendum, et malum vitandum. Et super hoc fundantur omnia alia praecepta legis naturae, ut scilicet omnia illa facienda vel vitanda pertineant ad praecepta legis naturae, quae ratio practica naturaliter apprehendit esse bona humana)".

46. Cf. ibid, Ia, q. 79, a. 12; Catechism of the Catholic Church, n. 1780.

47. Cf. R. Guardini, Liberté, grâce et destinée (tr. J. Ancelet-Hustache, Paris, 1969, 46-47): "To carry out the good means also to carry out that which renders existence fecund and rich. Thus, the good is that which preserves one's life and leads it to its fullness, but only when it is accomplished for itself.

48. Cf. St. Thomas Aquinas, Summa theologiae, Ia-IIae, q. 91, a. 2: "The rational creature is subject to divine providence in a more excellent way than all beings, inasmuch as it shares in providence, providing both for itself and for others. Hence it also partakes in the eternal reason, and from it has a natural inclination to its proper act and end; and this participation of the eternal law in the rational creature is called the natural law. (Inter cetera autem rationalis creatura excellentiori quodam modo divinae providentiae subiacet, inquantum et ipsa fit providentiae particeps, sibi ipsi et aliis providens. Unde et in ipsa participatur ratio aeterna, per quam habet naturalem inclinationem ad debitum actum et finem. Et talis participatio legis aeternae in rationali creatura lex naturalis dicitur)". This text is cited in John Paul II, Encyclical Veritatis splendor, n. 43. Cf. also Vatican Council II, Declaration Dignitatis humanae, n. 3: "The highest norm of human life is the divine law - eternal, objective and universal - whereby God orders, directs and governs the entire universe and all the ways of the human community by a plan conceived in wisdom and love. Man has been made by God to participate in this law, with the result that, under the gentle disposition of divine Providence, he can come to perceive ever more fully the truth that is unchanging."

49. Vatican Council II, Pastoral Constitution Gaudium et spes, n. 36.

50. Cf. St. Thomas Aquinas, Summa theologiae, Ia-IIae, q. 94, a. 2.

51. Cf. ibid., Ia-IIae, q. 94, a. 6.

52. Cf. Universal declaration of human rights, art.

53. Cf. ibid., article 16.

54. Cf. Aristotle, Politics, I, 2 (1253 a 2-3); Vatican Council II, Pastoral Constitution Gaudium et spes, n. 12, § 4.

55. St. Jerome, Epistolae 121, 8 [PL 22, col. 1024].

56. Cf. St. Thomas Aquinas, Summa theologiae, Ia-IIae, q. 94, a. 6: "But as regards the other, secondary precepts, the natural law can be destroyed from men’s hearts, either on account of evil persuasions—just as also in speculative matters errors may arise concerning necessary conclusions—or on account of depraved customs and corrupt habits, as some men did not consider stealing a sin, or even the vices against nature, as the Apostle says (Rom 1:24 ff.) (Quantum vero ad alia praecepta secundaria, potest lex naturalis deleri de cordibus hominum, vel propter malas persuasiones, eo modo quo etiam in speculativis errores contingunt circa conclusiones necessarias; vel etiam propter pravas consuetudines et habitus corruptos; sicut apud quosdam non reputabantur latrocinia peccata, vel etiam vitia contra naturam, ut etiam apostolus dicit, ad Rom. 1,24)".

57. St. Thomas Aquinas, Summa theologiae, Ia-IIae, q. 94, a. 4: "Practical reason considers the contingent matters with which human actions are concerned, and therefore, although there is a necessity in the general things, the more one descends to specific things, the more deficiency one finds. [...]. But in practical matters there is not the same practical truth or rightness for all men as regards specific things, but only as regards general things; and among those for whom there is the same rightness in specific things, it is not equally known to all of them. [...] And the more specific one makes the proposition, the more often will it fail to be right. [translation added – ed.] (Ratio practica negotiatur circa contingentia, in quibus sunt operationes humanae, et ideo, etsi in communibus sit aliqua necessitas, quanto magis ad propria descenditur, tanto magis invenitur defectus [...]. In operativis autem non est eadem veritas vel rectitudo practica apud omnes quantum al propria, sed solum quantum ad communia, et apud illos apud quod est eadem rectitudo in propriis, non est aequaliter omnibus nota. [...]. Et hoc tanto magis invenitur deficere, quanto magis ad particularia descenditur)".

58. Cf. St. Thomas Aquinas, Sententia libri Ethicorum, Lib. VI, 6 (Leonine ed., t. XLVII, 353-354): "Prudence considers not only universals, in which there is not action, but must also know singulars, since it is active, i.e., a principle of acting, and action regards singulars. Hence some who do not have knowledge of universals are more active in some particular things than those who have universal knowledge, because they have experience in the particulars. [...] Therefore since prudence is active reason, the prudent man must have each kind of knowledge, namely of universals and of particulars; or if he happens to have only one, it should rather be knowledge of particulars, which are closer to operation. (Prudentia enim non considerat solum universalia, in quibus non est actio; sed oportet quod cognoscat singularia, eo quod est activa, idest principium agendi. Actio autem est circa singularia. Et inde est, quod quidam non habentes scientiam universalium sunt magis activi circa aliqua particularia, quam illi qui habent universalem scientiam, eo quod sunt in aliis particularibus experti. [...]. Quia igitur prudentia est ratio activa, oportet quod prudens habeat utramque notitiam, scilicet et universalium et particularium; vel, si alteram solum contingat ipsum habere, magis debet habere hanc, scilicet notitiam particularium quae sunt propinquiora operationi)".

59. For example, experimental psychology underlines the importance of the active presence of the parents of both sexes for the harmonious development of the child's personality, and the decisive role of paternal authority for the construction of the child's identity. Political history suggests that the participation of all in decisions that regard the totality of the community is generally a factor of social peace and political stability.

60. At this first level, the expression of the natural law sometimes abstracts from an explicit reference to God. Certainly the openness to transcendence makes part of the virtuous behaviors that must be expected from the fulfilled man, but God is not necessarily recognized as the foundation and the source of the natural law, nor as the last end that mobilizes and hierarchizes the different virtuous behaviors. The explicit non-acknowledgment of God as the ultimate moral norm seems to prevent the "empirical" approach to the natural law from being constituted as properly moral doctrine.

61. St. Bonaventure, Commentarius in Ecclesiasten, cap. 1 (Opera omnia, VI, ed. Quaracchi, 1893, p. 16): "Verbum divinum est omnis creatura, quia Deum loquitur."

62. Cf. St. Thomas Aquinas, Summa theologiae, Ia-IIae, q. 91, a. 1: "Law is nothing other than a certain dictate of practical reason in the leader who governs some perfect community. Now it is evident, supposing that the world is ruled by divine providence, as was established in the First Part, that the whole community of the universe is governed by the divine reason. Hence the very plan [ratio] of the governing of things, which is in God as the ruler of the universe, has the account of law. And since the divine reason does not conceive something from a certain time, but has an eternal conception [...], this kind of law we must call eternal law. (Nihil est aliud lex quam quoddam dictamen practicae rationis in principe qui gubernat aliquam communitatem perfectam. Manifestum est autem, supposito quod mundus divina providentia regatur [...], quod tota communitas universi gubernatur ratione divina. Et ideo ipsa ratio gubernationis rerum in Deo sicut in principe universitatis existens, legis habet rationem. Et quia divina ratio nihil concipit ex tempore, sed habet aeternum conceptum [...], inde est quod huiusmodi legem oportet dicere aeternam)".

63. Cf. ibid., Ia-IIae, q. 91, a. 2: "Unde patet quod lex naturalis nihil aliud est quam participatio legis aeternae in rationali creatura" (It is therefore evident that the natural law is nothing other than the rational creature's participation in the eternal law [translation added – ed.]).

64. John Paul II, Encyclical Veritatis splendor, n. 41 – The teaching on natural law as the foundation of ethics is accessible by right to natural reason. History attests to this. But in fact, this teaching reached its full maturity only under the influence of Christian revelation. First of all, because the comprehension of the natural law as a participation in the eternal law is strictly linked with a metaphysics of creation. Now, although this is of right accessible to philosophical reason, it was truly presented and explained only under the influence of biblical monotheism. Secondly, because revelation, e.g., through the Decalogue, explains, confirms, purifies, and completes the fundamental principles of the natural law.

65. Does the theory of evolution, which tends to reduce species to a precarious and provisory equilibrium in the river of becoming, not perhaps call the very concept of nature radically into doubt? In fact, whatever its value on the level of empirical biological description, the notion of species answers a constant requirement of the philosophical explanation of living beings. Only recourse to a formal specificity, irreducible to the sum of the material properties, allows one to give an account of the intelligibility of the internal functioning of a living organism considered as a coherent whole.

66. The theological doctrine of original sin strongly underlines the real unity of human nature. This cannot be reduced to a simple abstraction, nor to a sum of individual realities. It indicates rather a totality that embraces all man who share the same destiny. The simple fact of being born (nasci) puts us in enduring relations of solidarity with all other men.

67. Boethius, Contra Eutychen et Nestorium, c. 3 [PL 64, col. 1344]: "Persona est rationalis naturae individua substantia (A person is an individual substance of a rational nature". Cf. Bonaventura, s., Commentaria in librum I Sentantiarum, d. 25, a. 1, q. 2; St. Thomas Aquinas, Summa theologiae, Ia, q. 29, a. 1.

68. Benedict XVI, Encyclical Spe salvi, n. 5.

69. Cf. also Athanasius of Alexandria, Traité contre les païens, 42 [Sources chrétiennes, 18, 195]): "As a musician who tunes the lire, by his art unites the low notes with the high notes, the middle notes with the others, in order to execute a single melody, so the Wisdom of God, the Word, holding the whole universe as a lire, unites the beings of the air with those of the earth, the beings of heaven with those of the air; combines the whole with the parts; leads all by his command and will; thus he produces, in beauty and harmony, a single world and a single order of the world."

70. The physis of the ancients, noting the existence of a certain non-being (matter), preserved the contingency of earthly reality and resisted the pretenses of human reason to impose on the totality of reality a purely rational deterministic order. Thus it left open the possibility of an effective action of human freedom in the world.

71. Cf. John Paul II, Letter to Families, n. 19: "The philosopher who formulated the principle of "Cogito, ergo sum", "I think, therefore I am", also gave the modern concept of man its distinctive dualistic character. It is typical of rationalism to make a radical contrast in man between spirit and body, between body and spirit. But man is a person in the unity of his body and his spirit. The body can never be reduced to mere matter: it is a spiritualized body, just as man's spirit is so closely united to the body that he can be described as an embodied spirit."

72. The ideology of gender, which denies all anthropological or moral significance to the natural difference of the sexes, is inscribed in this dualistic perspective. Cf. Congregation for the Doctrine of the Faith, Letter to the Bishops of the Catholic Church on the Collaboration of Men and Women in the Church and in the World, n. 2: "In order to avoid the domination of one sex or the other, their differences tend to be denied, viewed as mere effects of historical and cultural conditioning. In this perspective, physical difference, termed sex, is minimized, while the purely cultural element, termed gender, is emphasized to the maximum and held to be primary. [...] While the immediate roots of this second tendency are found in the context of reflection on women's roles, its deeper motivation must be sought in the human attempt to be freed from one's biological conditioning. According to this perspective, human nature in itself does not possess characteristics in an absolute manner: all persons can and ought to constitute themselves as they like, since they are free from every predetermination linked to their essential constitution."

73. John Paul II, Encyclical Veritatis splendor, n. 50.

74. The duty to humanize the nature in man is inseparable from the duty to humanize external nature. This justifies the immense effort made by men to emancipate themselves from the coercions of physical nature in the measure in which they hinder properly human values. The struggle against illness, the prevention of hostile natural phenomena, the improvement of the conditions of life are of themselves works that attest to the greatness of man called to fill the earth and to subdue it (cf. Gen 1:28). Cf. Pastoral Constitution Gaudium et spes, n. 57.

75. Reacting to the danger of physicalism and rightly insisting on the decisive role of reason in the elaboration of the natural law, some contemporary theories of natural law neglect, or rather reject, the moral significance of the natural pre-rational dynamisms. [According to these theories] the natural law would be called "natural" only in reference to reason, which would define the whole nature of man. To obey the natural law would be therefore reduced to acting in a rational manner, i.e., to applying to the totality of behaviors a univocal ideal of rationality generated by practical reason alone. This means wrongly identifying the rationality of the natural law with the rationality of reason alone, without taking account of the rationality inherent in nature.

76. Cf. St. Thomas Aquinas, Summa theologiae, IIa-IIae, q. 154, a. 11. The moral evaluation of sins against nature should take account not only of their objective gravity but also of the subjective dispositions, often attenuated, of those who commit them.

77. Cf. Gen 2:15.

78. Cf. Vatican Council II, Pastoral Constitution Gaudium et spes, nn. 73-74. The Catechism of the Catholic Church, n. 1882, clarifies that "certain societies, such as the family and the state, correspond more directly to the nature of man."

79. Cf. John XXIII, Encyclical Mater et Magistra, n. 65; Vatican Council II, Pastoral Constitution, Gaudium et spes, n. 26 § 1; Declaration Dignitatis humanae, n. 6.

80. Cf. John XXIII, Encyclical Pacem in terris, n. 55.

81. Cf. ibid., n. 37; Pontifical Council for Justice and Peace, Compendium of the Social Doctrine of the Church, nn. 192-203.

82. Cf. St. Thomas Aquinas, Summa theologiae, Ia-IIae, q. 95, a. 2.

83. St. Augustine, De libero arbitrio, I, V, 11 [Corpus christianorum, series latina, 29, 217]: "In fact a law that is not just does not seem to me to be a law"; St. Thomas Aquinas, Summa theologiae, Ia-IIae, q. 93, a. 3, ad 2: "Human law has the nature of law insofar as it in accord with right reason, and in this respect it is evident that it derives from the eternal law. But insofar as it departs from right reason, it is called an unjust law, and does not have the account of law, but rather of a certain violence. (Lex humana intantum habet rationem legis, inquantum est secundum rationem rectam, et secundum hoc manifestum est quod a lege aeterna derivatur. Inquantum vero a ratione recedit, sic dicitur lex iniqua, et sic non habet rationem legis, sed magis violentiae cuiusdam)"; Ia-IIae, q. 95, a. 2: "Every law made by men has the nature of law to the extent that it is derived from the natural law. But if in some matter it is not in accordance with the natural law, then it will no longer be law, but a perversion of law. (Unde omnis lex humanitus posita intantum habet de ratione legis, inquantum a lege naturae derivatur. Si vero in aliquo a lege naturali discordet, iam non erit lex sed legis corruptio)".

84. Cf. St. Thomas Aquinas, Summa theologiae, Ia-IIae, q. 97, a. 1.

85. For Saint Augustine, the legislator, to do a good work, should consult the eternal law; cf. St. Augustine, De vera religione, XXXI, 58 [Corpus christianorum, series latina, 32, 225]: "The legislator of temporal laws, if he is a good and wise man, consults that eternal law, about which it is given to no soul to judge, so that, according to its immutable rules, he may discern what should be commanded and what should be forbidden at a given time." In a secularized society, in which not all acknowledge the mark of this eternal law, the search for, defense, and expression of natural right by means of positive law guarantee this law its legitimacy.

86. Cf. St. Augustine, De Civitate Dei, I, 35 [Corpus christianorum, series latina, 47, 34-35].

87. Cf. Pius XII, Address given on March 23, 1958, in AAS 25 (1958) 220.

88. Cf. Pius XI, Encyclical Quadragesimo anno, nn. 79-80.

89. Cf. also Jn 1,3-4; 1 Cor 8,6; Heb 1,2-3.

90. Cf. Jn 3,19-20; Rom 1,24-25.

91. Vatican Council II, Pastoral Constitution Gaudium et spes, n. 22. Cf. St. Irenaeus of Lyons., Against Heresies, V, 16,2 [Sources chrétiennes, 153, 216-217]: "In prior ages it was certainly said that man was made to the image of God, but it had not appeared, since the Word was still invisible, to whose image man had been made, moreover, for this reason the resemblance was easily lost. But when the Word of God became flesh, he confirmed the one and the other; he showed the image in all its truth, becoming himself that which was his image, and restored the resemblance in a stable manner, rendering man completely like the invisible Father by means of the Word, from then on visible.

92. Cf. St. Augustine, Enarrationes in Psalmos, LVII, 1 [Corpus christianorum, series latina, 39, 708]: "The hand of our Maker in our very hearts has written this truth, "That which you would not have done to you, do not do to another" Of this truth, even before that the Law was given, no one was suffered to be ignorant, in order that there might be some rule by which even those to whom Law had not been given might be judged. But lest men should complain that something had been wanting for them, there has been written also in tables that which they do not read in their hearts. For it was not that they did not have it written, but that they did not want to read it. There has been set before their eyes that which they would be compelled to see in their conscience; and as if from without the voice of God were brought to them, to his own inward parts has man been thus driven. (Quandoquidem manu formatoris nostri in ipsis cordibus nostris scripsit: “Quod tibi non vis fieri, ne facias alteri”. Hoc et antequam lex daretur nemo ignorare permissus est, ut esset unde iudicarentur et quibus lex non esset data. Sed ne sibi homines aliquid defuisse quaererentur, scriptum est et in tabulis quod in cordibus non legebant. Non enim scriptum non habebant, sed legere nolebant. Oppositum est oculis eorum quod in conscientia videre cogerentur; et quasi forinsecus admota voce Dei, ad interiora sua homo compulsus est)". Cf. St. Thomas Aquinas, In III Sent., d. 37, q. 1, a. 1: "Necessarium fuit ea quae naturalis ratio dictat, quae dicuntur ad legem naturae pertinere, populo in praeceptum dari, et in scriptum redigi [...] quia per contrariam consuetudinem, qua multi in peccato praecipitabantur, iam apud multos ratio naturalis, in qua scripta erant, obtenebrata erat"; Summa theologiae, Ia-IIae, q. 98, a. 6.

93. Cf. Sir 24,23 (Vulgate: 24,32-33).

94. Cf. St. Thomas Aquinas, Summa theologiae, Ia-IIae, q. 100.

95. The Byzantine liturgy of St. John Chrysostom expresses well the Christian conviction when it puts in the mouth of the priest who blesses the deacon in thanksgiving after the communion: "Christ our God, who are the fulfillment of the Law and the Prohets, and have fulfilled the whole mission you received from the Father, fill our hearts with joy and gladness, at all times, now and always, forever and ever. Amen."

96. Cf. Gal 3,24-26: "So that the law was our custodian until Christ came, that we might be justified by faith. But now that faith has come, we are no longer under a custodian; for in Christ Jesus you are all sons of God, through faith." On the theological notion of fulfillment, cf. Pontifical Biblical Commission, The Jewish People and Their Sacred Scriptures in the Christian Bible, especially n. 21.

97. Cf. Mt 22,37-40; Mk 12,29-31; Lk 10,27.

98. Cf. Lk 6,27-36.

99. Cf. Lk 10,25-37.

100. Cf. Jn 15,13.

101. Cf. also Jer 31,33-34.

102. Cf. St. Thomas Aquinas, Summa theologiae, Ia-IIae, q. 106, a. 1: "That which is most powerful in the law of the new testament, and in which its whole power consists, is the grace of the Holy Spirit, which is given through the faith of Christ. And therefore the new law is principally the grace of the Holy Spirit, which is given to the Christian faithful. (Id autem quod est potissimum in lege novi testamenti, et in quo tota virtus eius consistit, est gratia Spiritus sancti, quae datur per fidem Christi. Et ideo principaliter lex nova est ipsa gratia Spiritus sancti, quae datur Christi fidelibus)".

103. Cf. ibid., Ia-IIae, q. 108, a. 1, ad 2: "Therefore since the grace of the Holy Spirit is like an interior habit poured into us inclining us to work rightly, it makes us do freely the things fitting to grace, and avoid the things opposed to grace. Thus the new law is called the law of freedom in two ways. In one way, because it does not restrict us to doing or avoiding anything except things which are of themselves necessary for or opposed to salvation, which fall under the precept or prohibition of the law. Second, because it makes us fulfill precepts or prohibitions of this kind freely, insofar as we fulfill them from the interior impulse of grace. And on account of these two things the new law is called the “law of perfect freedom” in Jam. 1:25. (Quia igitur gratia Spiritus sancti est sicut habitus nobis infusus inclinans nos ad recte operandum, facit nos libere operari ea quae conveniunt gratiae, et vitare ea quae gratiae repugnant. Sic igitur lex nova dicitur lex libertatis dupliciter. Uno modo, quia non arctat nos ad facienda vel vitanda aliqua, nisi quae de se sunt vel necessaria vel repugnantia saluti, quae cadunt sub praecepto vel prohibitione legis. Secundo, quia huiusmodi etiam praecepta vel prohibitiones facit nos libere implere, inquantum ex interiori instinctu gratiae ea implemus. Et propter haec duo lex nova dicitur lex perfectae libertatis, Iac 1,25)".

104. St. Thomas Aquinas, Quodlibeta, IV, q. 8, a. 2: "The new law, which is the law of freedom [...] is constituted by moral precepts of the natural law, by the articles of faith, and by the sacraments of grace (Lex nova, quae est lex libertatis [...] est contenta praeceptis moralibus naturalis legis, et articulis fidei, et sacramentis gratiae)."

105. John Paul II, Address of January 18, 2002, in AAS 94 (2002) 334.