A man is a dangerous thing, a man who has nothing to lose is even more dangerous.
一个人是危险的，一个没有什么可失去的人更危险。
The only limit to our realization of tomorrow will be our doubts of today.
It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge.
心理学是我们如何驾驭存在的研究。