Civilization is a stream with banks. The stream is sometimes filled with blood from people killing, stealing, shouting and doing the things historians usually record, while on the banks, unnoticed, people build homes, make love, raise children, sing songs, write poetry and even whittle statues. The story of civilization is the story of what happened on the banks.

The method of psychology must be as exact as the methods of the natural sciences.

一个理论的优雅不仅在于其数学表述，还在于其在一个统一框架下连接不同现象的能力。

化学的乐趣在于实践，而不仅仅是发现。

物理学的美丽在于它能够用简单的原理描述复杂的事物。