What makes you think economists don't try to study all those things? Even the caricatured "homo economicus" model, while defined as being perfectly rational in the methods, had an utility function (ie, goals) that was completely subjective; the idea that it was necessarily an Ebenezer Scrooge type is nonsense.
I derive my conclusion based on articles I read in financial/economic press.
I know that's not a very good heuristic, but somehow I feel like economic thought is mostly based on mathematical models and political science, while the study of human behavior and more generally, human mind is left to psychologists/psychiatrists as something marginally useful.
I think economics and society in general would benefit greatly from a more unified theory.
I'm sure that hedge funds do exactly this and reap great returns as a result.
And political science isn't concerned with the behaviour of people or groups?
>benefit greatly from a more unified theory.
Economists are generally concerned with things that can be measured. As others have pointed out, psychological findings are often irreproducible. So what's the point in incorporating them into models?
And this all ignores the fact that behavioural economics is a popular and growing field...
