"When Ratz saw how intelligent Jancsi was, he began giving him private lessons. . . . [Ratz] felt so privileged to tutor a phenomenon like Jancsi that he refused any money for it. His compensation was more subtle: the brush with a special kind of mind; the privilege of training that mind in a discipline that both of them loved."
January 1, 1970
https://en.wikiquote.org/wiki/John_von_Neumann