The study of mental processes requires both experimental and comparative methods.

天也有喜怒哀乐的情感，与人类的情感是相通的。

There is no easy walk to freedom anywhere, and many of us will have to pass through the valley of the shadow of death again and again before we reach the mountaintop of our desires.

语言中最具破坏性的一句话是：“一直都是这样做的。”

The future is hidden even from those who make it.

——1905年8月13日在东京中国留学生欢迎大会上的演说