The July 5 issue of Newsweek has an interesting piece (not online) about the weird interaction between money, the brain, and social psychology. Try this experiment: Take any two people. Give one of them (A) $10 and tell them they have to offer some of the money to the other person (B), who is free to accept or reject the offer. Game over. The goal is for both parties to walk away with as much money as possible.
As predicted by John (“A Beautiful Mind”) Nash, A should offer $1 to B, and B should accept the offer. But what in fact happens in the vast majority of cases where the experiment is tried is that low offers of $1 or $2 are almost universally rejected by B, even though it serves B’s best interests to accept the offer. This is where funny motivators like pride and dignity interlope, overriding pure reason. B is insulted that A would keep most of the money for themselves, and so rejects the offer altogether. And for similar reasons (sensitivity to the prospect of insulting another), most people playing A don’t offer $1 or $2, but something closer to a 50/50 split, e.g. $4.
It makes no mathematical sense for B to reject any offer, and it makes no mathematical sense for A to offer more than $1, but that’s how humans interact. Interestingly, people will offer or accept just $1 when playing the same game against a computer. But the part that I found really fascinating is that there is one group of people who play the game “rationally” (I put rational in quotes, because I do think that treating humans fairly is a rational thing to do, even if not mathematically sensible) — autistics will generally offer or accept $1, since they lack the sense of social fabric that most people experience.