I don’t think we economists have quite gotten to the bottom of sleep. To the extent we think of it at all, I think we are inclined to think of it as an input in a kind of Gary Becker way. More sleep = less time for production and consumption, but too little sleep harms the productivity of both production and consumption. Solve for the optimum (in which you will be slightly over-tired all the time).In this model the objective function is to maximize the present value of all future WAKING consumption. Adopting this approach, studies showing that more sleep = longer life are not very persuasive, because the effect would have to be huge before more total hours would translate into more waking hours, particularly since the old-age hours are highly discounted. (Of course some people believe the decades-away future may bear huge positive shocks – new therapies, new kinds of experiences, etc.- and this would offset the discount.)I don’t find this model very convincing. Many people don’t view time spent sleeping as time wasted. Is enjoying a good nap merely a synonym for enjoying subsequent consumption more intensively, or do we perhaps actually enjoy a good nap? (My 17 year old son is adamant that he enjoys sleeping and sometimes it seems to be his favorite activity.)
And he follows up with this:
…My conjecture is that these wake drugs will mostly change the intertemporal substitutability of sleep. It will be easy to “borrow” wakefulness the night before an exam, during an extended battle, etc. But the total amount of lifetime sleep will be little affected. Qui vivra, verra.Could also be related to the frequency and pleasantness of dreams. I have frequent and sometimes quite interesting dreams so giving up on sleep would be more of a sacrifice for me than for someone who has few dreams or frightening ones.