there is a lot of evidence to show consumers do not make entirely rational choices. Even if they did, trying to determine a utility function for a consumer woul

there is a lot of evidence to show consumers do not make entirely rational choices. Even if they did, trying to determine a utility function for a consumer would still fail. For instance, can you even with certainty determine your own utility function. Of course; I never claimed otherwise. It's certainly true that any person's utility function is at least partly unknown to them, and in any case changes over time. As a result it has little value as a predictive tool. But that doesn't mean that it doesn't exist. Ludwig von Mises attacks this head-on in Human Action (http://en.wikipedia.org/wiki/Human_Action http://en.wikipedia.org/wiki/Human_Action ). It's undeniable that at any juncture, the action that a person takes is based on some judgment, conscious or not (and quite possibly mistaken), that the chosen action delivers a greater utility than its alternatives. Thus, the hypothetical postdoc-cum-bartender is deciding -- for reasons that we don't know, but real all the same -- that he would prefer to do his research over bartending, even to the extent of giving up $60K to do so. Who are we to second guess his decision? Precisely because, and not in spite of, the fact that his reasons are inscrutable, we can only assume that he's making the best call he can. By what right can we override it? And more to the point, if his/her university is providing such a valuable career for him, who are we to say that they must sweeten the pot and throw in even more money?