真相很少纯粹，也绝不简单。
The truth is rarely pure and never simple.
——《在山西实业界学界及各党派欢迎会的演说》（1912年9月20日）
Confidence isn't optimism or pessimism, and it's not a character attribute. It's the expectation of a positive outcome.
The best scientists are those who remain humble in the face of nature’s complexity.
粒子的概念只是一个近似，在经典极限下有效。