每个出口都是另一个地方的入口。

"The more you try to understand the game, the less you know."

Mathematics is not a spectator sport—you have to engage with it to appreciate its beauty.

The value of an idea lies in its practical consequences.

Youth is not a time of life; it is a state of mind; it is not a matter of rosy cheeks, red lips and supple knees; it is a matter of the will, a quality of the imagination, a vigor of the emotions; it is the freshness of the deep springs of life.