There’s a funny story in Robert Heilbroner’s 1953 book The Worldly Philosophers (which has been republished dozens of times):

One evening Keynes was having dinner with Max Planck, the physicist who was responsible for the development of quantum mechanics. Planck turned to Keynes and told him that he had once considered going into economics himself. But he decided against it – it was too hard. Keynes repeated this story with relish to a friend back at Cambridge. “Why, that’s odd,” said the friend. “Bertrand Russell was telling me just the other day that he’d also thought about going into economics. But he decided it was too easy.” Continue reading →