Every choice that you make is the best possible choice at the time you make it, and given what you know. If you considered other timeframes, had different goals, more time to think about it, or different information, you might make a different choice, but you don’t.
Consider drug use: It’s not in your interest in the long term, but it may be if you prioritize feeling good in the short term. You can therefore define the use of addictive substances as rational within narrowly defined time windows and circumstances, but it doesn’t make sense to define taking drugs as rational once you sufficiently expand your time horizon and take into account the long-term consequences. Other choices make sense if you only consider your own self-interest, but not if you consider its impact on others.
This is the problem with a recent blog post by economist Arnold Kling, in which he suggests that peoples reading less fiction is a rational choice. He seems to assume that the choice we make are indicative of what the rational choice is. I think this may be true if it comes to short-term convenience and enjoyment, but that doesn’t mean it’s also true when considering a longer time horizon.
Nehaveigur 