The deepest problems in mathematics often arise from the simplest questions.

成功的交易者必须与两个强大的敌人斗争：市场和他自己。

The state of nature has a law of nature to govern it, which obliges every one: and reason, which is that law, teaches all mankind, who will but consult it, that being all equal and independent, no one ought to harm another in his life, health, liberty, or possessions.