数学不是一项观赏性运动。
"Mathematics is not a spectator sport."
发散级数是魔鬼的发明,基于它们的任何证明都是一种耻辱。
You can fool all the people some of the time, some of the people all the time, but you cannot fool all the people all the time.
To the artist there is never anything ugly in nature.