So everybody lives in and around San Francisco, everybody eats McDonald’s double cheeseburgers, and everybody drives a Prius, everybody drinks one beer chosen by the experts — maybe that’s not the utopia you had in mind, but you could make a pretty good empirical case that this arrangement represents the right metropolis, the right food, and the right car, etc.

It is easy to see that these results are absurd. For example, sending 300 million people to live in the Bay Area might change some of the things that people like about the region. (But sending millions of people into the health-insurance market will have a negligible effect on prices, market structure, or incentives? Right?) Fine, pick your own answer — but it is important to recognize that the real absurdity here is not in the answer to each question, but in the question itself. The idea that there exists a single “right” urban cluster or a single “right” automobile or meal fails to take into account any number of variables, not least of which is the fact that people do not all want or need uniformly the same things, and that it is not really our business to tell them what they should want, even when we believe we know better — even when we have a pretty good body of evidence suggesting that we know better.