改变世界的唯一方法是改变自己。
The only way to change the world is to change yourself.
The essence of mathematics lies in its freedom.
任何一样东西，你渴望拥有它，它就盛开。一旦你拥有它，它就凋谢。
永远不要停止学习；世界总是在变化。
The purpose of psychology is to understand how we cope with the world.
Love doesn't just sit there, like a stone; it has to be made, like bread, remade all the time, made new.
唯一真正的自由是说“不”的自由。