Death

https://www.econlib.org/an-ageless-hypothetical-horpedahls-critique/?unapproved=272262&moderation-hash=afd8e54b8553f78a7582d6bf8380078e#comment-272262

 The other thing you mention is discount rates. Young people are more impatient.  It must also be allowed, though, that we can't push hard on the rationality assumption here, if by that we mean making unbiased decisions on average. You're only young once. Thus, it's quite possible for young people to systematically err in taking too much risk and spending too little on staying alive,  in the sense that if they were perfectly informed they would agree their decisions were mistaken. It's like Marriage and Crime and Buying a House: the first decision may well be wrong, but you're stuck with it.     Of cousre, you're also only old once. So it could be, and I suspect is, that it is the OLD people who are systematically mistaken--- too nervous, too fearful, too risk averse.  Plus, their brains don't work as well in many respects. Old people fear death, but maybe it isn't as bad as they think, nor Life as good.