证明是一种用于使他人相信数学陈述为真的工具。

A great business at a fair price is superior to a fair business at a great price.

The best moments in our lives are not the passive, receptive, relaxing times… The best moments usually occur if a person’s body or mind is stretched to its limits in a voluntary effort to accomplish something difficult and worthwhile.

量子力学的数学形式不仅是一种工具，更是一种揭示自然深层结构的语言。