How and Why Darwin Got Emotional about Race

In The Expression of the Emotions in Man and Animals, published in 1872, Charles Darwin purported to show that, around the world, humans of every race express their emotions in the same ways: crying when sad, smiling when happy, and so on. He claimed that this sameness afforded a “new argument” for the common descent of all the human races from a single ancestral stock. What follows is a new account of the origins of the empirical research underpinning this argument as well as the bravura deep-time reconstruction with which Darwin fleshed it out. Understanding how and why Darwin first began to collect evidence on emotional expression across the human races throws new light on the recently controversial question of where, if anywhere, his scientific work reflected his lifelong hatred of black slavery. It also suggests a new solution to an old puzzle: the notoriously “non-Darwinian” character of Darwin’s explanations in the Expression.