Impromptus

I thought economists assume that, everything else being equal, people tend to act in their own self-interest?

It’s more exact than that, but yes. The thing is that people DON’T act in their own self interest all the time – either due to psycological hangups, lack of freedom, lack of knowledge, or out and out idiocy. Assuming that people will act in their own self interest presumes perfect free will.

I don’t follow. If I’m acting rationally (in the game theory/economics sense), then I only have one choice. Isn’t that the opposite of free will?

See, this is why I don’t discuss philosophy much. I was thinking of the whole thing WRT being able to successfully and accurately evaluate what is the best course of action, as well as actually being able to take it, if you want.

I think that perhaps what I was trying to express is best shown here: http://economistsview.typepad.com/economistsview/2007/01/george_akerlof_.html

It's more exact than that, but yes. The thing is that people DON'T act in their own self interest all the time – either due to psycological hangups, lack of freedom, lack of knowledge, or out and out idiocy. Assuming that people will act in their own self interest presumes perfect free will.