如果你不犯错，说明你不够努力。
If you don't make mistakes, you're not trying hard enough.
《在陆军军官学校开学典礼的演说》（1924年6月16日）
The cement industry must evolve or become obsolete.
The end of wisdom is to dream high enough to lose the dream in the seeking of it.
心理学的真理是在现实世界中有效的东西。