" It was a grand triumph but not one easily understood. The skeptical Silverstein came up to Eddington and said that people believed that only three scientists in the world understood general relativity. He had been told that Eddington was one of them. The shy Quaker said nothing. "Don't be modest, Eddington," said Silverstein. Replied Eddington, "On the contrary, I'm just wondering who the third might be. "

― Walter Isaacson , Einstein: The Life of a Genius