GMVarun wrote:My whole point is that for economists a serial killer can be rational. If the serial killer's objective is to kill person x, has only available modes of behavior X,Y, Z, and X costs the least of the three, and if the serial killer choose mode X, killing someone, the serial killer is "rational" according to economic choice theory. Very few people would think that a serial killer can be rational.
oh I see
Rationality refers to achieving your objective in the most efficient manner. Economists generally care more about the direction of the behavior rather than the magnitude (though there are obviously cases where we care about the magnitude and we might try to measure the magnitude in cases where we might not care about it so much). Say we increase the price of good x, assuming "rational behavior", we economists think that the consumption of good x will go down. How much is an empirical question - which we can try to answer, but the models will tell us the direction (that consumption will go down.. not up). Iono, I think it's a useful way of analyzing behavior .. and, on the margins, is accurate.
well that gets to the problem I have with economics in general... decision making is complex and subjective... even if you take out the individual subjectivity and take it to the population level it is still subjective. Choices are always based on costs and benefits (and I guess sometimes categorical imperatives) but costs and benefits are kind of like directions too, one goes one way the other goes in the opposite, without knowing magnitude you don't know the resultant direction...
and economics has no good answer for figuring out the magnitude of any of these directions and so ultimately it doesn't do a whole lot of good anyway.