Adam Smith's uncritically enthusiastic modern disciples portray his invisible hand theory as saying that market forces reliably harness selfish individuals to serve the common good. That's often true, but as Darwin recognized clearly, many traits that serve the interests of individual animals make life more difficult for larger groups.

Many social critics wag their fingers at what they perceive to be frivolous luxury spending. But that misses the point that consumption norms are local. It's not just the rich who spend more when they get more money. Everyone else does, too. The mansions of the rich may seem over the top to people in the middle, but the same could be said of middle-class houses as seen by most of the planet's seven billion people.

No society has ever succeeded without a decent government.

We could curtail private spending by several trillion dollars a year without requiring painful sacrifices from anyone. That would be more than enough to rebuild our crumbling infrastructure and eliminate government indebtedness once and for all.

Questions like, "Is my suit OK?", or "Is my job performance satisfactory?", are impossible to think about in the absence of a suitable frame of reference. For an interview suit to serve its purpose, it must make you look good relative to other candidates for the job you want. For your job performance to be satisfactory, it must compare favorably with the performance of others who want the same promotion you do. As Charles Darwin saw clearly, much of life is graded on the curve, and conventional economic models completely ignore that fact.

If the search is for examples that contradict the predictions of standard economic models, a good rule of thumb is to start in France.

Unless we can act collectively, there would be no way to defend ourselves, no way to define or enforce property rights. We couldn't curb congestion or pollution or build and maintain public infrastructure.