If something works, let it work.

At the end of World War II, the mathematician and physicist Stanislaw Ulam asked the Nobel laureate in economics, Paul Samuelson, to name "a proposition in all of the social sciences that is both true and non-trivial."

It is an episode I would have liked to discuss in depth in Zombies of Marx—available on Amazon:

but I would have had to double the size of the book.

Whether the social sciences—and therefore also economics—have ever, in their history, managed to formulate a proposition capable of fully describing the functioning of at least one complex human phenomenon is difficult to say.

Samuelson answered Ulam only in 1969, after a long reflection. He pointed to "comparative advantage in international trade."

This is the hypothesis that a nation benefits from importing goods that it cannot produce efficiently and specializing in markets where it has the greatest advantage, rather than protecting domestic industries.

So far, it has worked quite well, and I believe that one of the propositions all economists agree on is: "If something works, let it work." International trade, when it is free and fair, works, and there is no reason to disrupt it when it is doing its job.

Economics is a complicated subject. It seeks to understand the functioning of the most complex system that exists: the network of human collaboration realized through exchange.

This is a network that constantly changes shape, is influenced by random events, and is determined by the most powerful force in the universe: human will.

I believe Ulam’s question was a trap: complex systems have behavior that is difficult to predict.

Small changes can produce disasters, and seemingly drastic interventions can leave the established equilibrium entirely unchanged. In this kind of system, finding a universal law is truly difficult.

However, economics has taught us at least one non-trivial thing: when the market is a place of collaboration, it is possible to create a system that benefits everyone; when someone tries to use force to dominate the market, they end up facing consequences they had never even imagined.

If something works, only a fool tries to change it.