The following puzzle compares the happiness of a man who thinks some of the goods he generally seeks in life are realized with the happiness of a man in the case where those goods are realized, but he thinks they are not. Besides being an interesting thought exercise, it might be helpful for shedding some light on what is involved in the notion of happiness. Warning! The scenario presented is not a pleasant one! A nicer scenario that would so starkly focus on the same issues did not, however, occur to me.
Twenty years from now, two twins, who are both happily married and love their families, have had a falling out with a extremely brilliant, wicked, and rich scientist, who determines to destroy their lives. He kidnaps them, locks them in separate rooms, and offers each of them the choice between the following two options:
(1) I will kidnap your wives and children, and torture them for the rest of your life in the most horrible ways thinkable, but by careful use of precise memory-altering drugs, planted evidence, false witnesses, etc., I will see to it that you are convinced without the slightest doubt that your wife and children died a a heroic or a peaceful death.
(2) I will kidnap your wives and children, and by the use of precise memory-altering drugs so that they no longer remember you at all, arrangement of circumstances, etc., I will do my best to see to it (there's a 95%-99% chance of success) that they are quite happy in their new life, but by use of similar drugs, falsified evidence, etc., I will ensure that you are convinced that they are being tortured and suffering horribly.
The first of the twins chooses the first option, while the second chooses the second. The wicked scientist keeps his threats and promises. Five years later, the first man is still convinced that his family died heroically, though they are in fact still suffering. The second man is still convinced, and reasonably on the basis of the evidence available to him, that his family is suffering, though they are not.
The questions for you, dear reader, are the following: on the basis only of the statements provided: (1) at this point in time, five years after the deed, which of the two men is happier? (2) Taken as a whole, whose life is happier?