Conspiratorial thinking has always been a part of American political thought, but in recent years, fringe beliefs seem to be moving more into the mainstream. People who push disproven conspiracies like the 2020 election fraud lie and the Obama birther myth or rile support for radical groups like QAnon hold major political offices, sit in Congress, and even formerly occupied the White House.

Why do people believe far-out ideas that have been repeatedly debunked? Skeptic Magazine founder Michael Shermer walks us through the psychology of conspiracy theories, their appeal and the methods we need to detect them. Shermer’s new book is, Conspiracy: Why the Rational Believe the Irrational.