最激动人心的发现往往来自于以全新的方式看待老问题。

学习数学的最好方法就是去做数学。

有成就感的人会把世界看成一个友好的世界，并乐于看到它照原样保持下去，但失意者却会乐于看到世界急遽改变。

The battle of life is already half won by the young man who is brought personally in contact with high officials; and the great aim of every boy should be to do something beyond the sphere of his duties--something which attracts the attention of those who over him.

被视为行为系统的人类其实相当简单。我们行为表面上的复杂性很大程度上反映了我们所处环境的复杂性。

可持续性不是一种趋势，而是我们对后代的责任。