The state, therefore, has not existed from all eternity. There have been societies that did without it, that had no notion of the state or state power. At a certain stage of economic development, which was necessarily bound up with the split of society into classes, the state became a necessity.

小孩是在敏感期学会调适自己并获得特定能力的。

成功不是幸福的关键。幸福是成功的关键。如果你热爱你所做的事情，你就会成功。

"The only way to do great work is to love what you do."

I want to liberate America from fear. I want people to be afraid of the things that are really scary, like war and famine, not their neighbor because he has a different religion.

进步更有效的原因似乎在于青年时期大脑可塑性强的良好教育，以及成年后达到的高标准卓越。