变革在开始时最难，在中间最混乱，在结束时最好。

动力学的方程在用变分法的语言表达时是完全的。

诗歌应当像火焰一样燃烧。

生活是记忆与遗忘之间永无止境的斗争。

I think that we communicate only too well, in our silence, in what is unsaid, and that what takes place is a continual evasion, desperate rearguard attempts to keep ourselves to ourselves.

尽可能广泛地涉猎各门学问，并且尽可能深入地择一钻研。

教师不应该像往空容器里倒知识那样教学，而应该像点燃火焰那样教学。