尽管儿童的举止有比较大的自由，但总的说来，他们给人一种非常有纪律的印象。

The meaning of earthly existence lies not, as we have grown used to thinking, in prospering but in the development of the soul.

The only limits in life are the ones you make.

最好的科学不是来自随波逐流，而是来自追求你的好奇心。