Not long after the second world war, the Jewish, German-born political philosopher Leo Strauss coined the term reductio ad Hitlerum. It suggests that simply comparing something to Adolf Hitler does not inevitably taint it with the Nazi dictator’s terrible crimes. Hitler was a vegetarian, but that doesn’t make all vegetarians bad people.
When the internet arrived several decades later, attorney Mike Godwin updated Strauss. “As an online discussion grows longer,” he said, “the probability of a comparison involving Nazis or Hitler” increases.