Ex ante and ex post: What Does Rod Stewart Really Know Now? by Art Carden, Walter Block, Stephen Carson (Washington University in St. Louis, Loyola University in New Orleans)
Do we really know whether or not we have "maximized" utility in any meaningful sense of the word, or do we just know that we are "happy" or "sad?" We argue that we can never know objectively whether or not utility has been maximized; however, people acting on a free market are sufficiently close to the decision as to be able to hazard a better guess about their opportunity costs than policymakers.