A proof is a device for convincing someone else that a mathematical statement is true.

"We are all in the gutter, but some of us are looking at the stars."

The biggest risk is not taking any risk.

你应该向你的竞争对手学习，但永远不要抄袭。抄袭你就会死。

λ演算是一种表示函数及其应用的形式体系。