A mathematician is a person who can find analogies between theorems; a better mathematician is one who can see analogies between proofs and the best mathematician can notice analogies between theories.
"Banach Spaces and Their Applications in Analysis: Proceedings of the International Conference at Miami University, May 22-27, 2006, in Honor of Nigel Kalton's 60th Birthday" by Beata Randrianantoanina, Narcisse Randrianantoanina, Walter de Gruyter, (p. 5), 2007.
