A long time ago, I happened upon a cartoon in some publication or other. A single frame—in the vein of Gary Larson—depicted thousands of sheep rushing headlong off a cliff. In the middle of this great multitude, one particular sheep moved in the opposite direction. “Excuse me…excuse me…excuse me,” it bleated. That scene came to mind recently as I read Douglas Murray’s latest book. He takes his title and inspiration from Extraordinary Popular Delusions and the Madness of Crowds (1841), that oddly compelling 19th-century miscellany by Charles Mackay, a book that is still in print and widely read today. This is because it concerns the most bestial part of human nature: the herd mentality.
“Men,” Mackay writes, “…think in herds; it will be seen that they go mad in herds, while they only recover their senses slowly, and one by one.” This may be overly optimistic. It isn’t that men recover their senses so much as they move on to some new madness. He admits as much elsewhere in the book:
We find that whole communities suddenly fix their minds upon one object, and go mad in its pursuit; that millions of people become simultaneously impressed with one delusion, and run after it, till their attention is caught by some new folly more captivating than the first.
Advances in science and technology have...