All we have to do to cease being a “cancer” on the planet is turn the clock back half a billion years—roughly 1,000 times the span since Homo sapiens emerged—and Mr. Graber will get off our case. True, that would mean no airplanes, polio vaccines, metals, dentistry, Mozart, air-conditioning, plans to go to Mars. But who needs those things anyway? It is more important that we again become part of nature, as we were, happily, eons ago.

This third rock from the sun can now support seven-plus billion people prosperously (or could if everyone would adopt the principle of free enterprise) thanks to modern science, technology, medicine, etc. If Mr. Graber had his way, billions of people would be wiped out.

Economists make predictions only to show we have a sense of humor. If we knew the future course of the economy, we’d all be rich. We’re not. Nevertheless I’m going to go out on a limb and make a prediction. Mr. Graber won’t be canceled. That’s not because his article is so old; others have been punished for views expressed longer ago and subsequently disavowed. (In a Wednesday email, Mr. Graber wrote that he regrets “some of the harsh language I used” but still believes “mankind is destroying nature.”)