“Our country is in a crisis that threatens to set us back 400 years.

I know this sounds dramatic, and I am not talking about politics, I’m talking about reversing the Age of Reason, which ushered in a period of unprecedented intellectual, economic, and social growth. The Enlightenment, as it is also called, drew a line in the sand between rumor and fact, between testable hypotheses and anecdote, and between demonstrable facts and nonsense. Prior to the Age of Reason, people who heard voices in their heads might have been drowned or burned at the stake as witches; by the 20th century we had identified a biological disease that causes this (schizophrenia) and developed drugs to treat it. The Age of Reason led us to the germ theory of disease, penicillin, and—although it took a while and is still not ubiquitous—women’s rights, child labor laws, and a reduction in racism.