The efficient market hypothesis states the value of a stock is the expected future dividends given all public information (or all private information, if you prefer the strong form).
This is a good example of how academic economics think because on the one hand it is consistent with your claim that "you'd have to take into account everything that goes through the minds of the entire world population" and on the other hand it "ignores the human factor" in that the efficient market hypothesis assumes that emotion, mass psychology, etc. don't enter into stock markets.
I think economists actually ignore the "human factor" in the right way, in order to get some reasonable approximation of reality. The problem is that adding the human factor back in doesn't result in a mathematically elegant theory, just a more complicated model. So they are unable to progress in the same way as physics can.
This is a good example of how academic economics think because on the one hand it is consistent with your claim that "you'd have to take into account everything that goes through the minds of the entire world population" and on the other hand it "ignores the human factor" in that the efficient market hypothesis assumes that emotion, mass psychology, etc. don't enter into stock markets.
I think economists actually ignore the "human factor" in the right way, in order to get some reasonable approximation of reality. The problem is that adding the human factor back in doesn't result in a mathematically elegant theory, just a more complicated model. So they are unable to progress in the same way as physics can.