I’m curious, is there anyone on the stage that does not believe in evolution?” came the question at the first Republican presidential debate. Much has been made of the fact that three candidates raised their hands. The candidates were not allowed to elaborate, but what should they have said had they more time?

What makes the original question difficult to answer yes or no is that “evolution” can mean many things. It can range from simple change over time, which no one disputes, to the specifically Darwinian idea that all of life’s diversity — from bald eagles to newborn baby boys — is owed to the mindless process of natural selection and random mutations and nothing more. As the eminent Harvard Paleontologist George Gaylord Simpson famously summarized it, “Man is the result of a purposeless and natural process that did not have him in mind.”