《三民主义·民族主义·第六讲》（1924年3月2日）

Society can and does execute its own mandates， and if it issues wrong mandates instead of right， or any mandates at all in things with which it ought not to meddle， it practices a social tyranny more formidable than many kinds of political oppression， since， though not usually upheld by such extreme penalties， it leaves fewer means of escape， penetrating much more deeply into the details of life， and enslaving the soul itself.

Men and women differ in their reproductive strategies because they have faced different adaptive problems throughout evolutionary history.

The dead are always looking down on us, they say. But we don't look back.

不要等待机会，要创造机会。

形式系统的发展彻底改变了我们对数学的理解。