Some months ago, during the middle of winter, I was sitting on the floor playing with my then roughly five month year old son when my wife came in from outside and stuck her icy hands on me. Mucking around, I pretended to cry, and the next thing my son bursts into tears, something he rarely does if he’s not hungry. Now as far as I can recall he’d never seen anyone else cry up to this point in his life, and we were mystified how he knew that it was an event to be upset about.
So I was looking at this article in The Economist about how our knowledge of facial expressions is likely inherited not learned, and was surprised to see that Charles Darwin had done something similar.
Darwin also believed babies are born able to recognise the facial expressions of others. His first child had suddenly assumed a melancholy expression in an experiment where the maid pretended to weep, even though the boy had apparently never before witnessed another person crying. This, Darwin thought, suggested that his son could not have learned that crying is linked to sadness and must have somehow inherited the knowledge.