数学不是关于数字、方程、计算或算法的：它是关于理解的。
Mathematics is not about numbers, equations, computations, or algorithms: it is about understanding.
The only information we can legitimately derive from aesthetic and moral experiences is information about our own mental and physical make-up.
Everything that happens once can never happen again. But everything that happens twice will surely happen a third time.
"There is no sun without shadow, and it is essential to know the night."
"Friendship isn't about who you've known the longest. It's about who walked into your life and said, 'I'm here for you,' and proved it."