爱不是容易的事。
人类并非在母亲生下他们的那一天就一劳永逸地诞生了，生活迫使他们一次又一次地重生自己。
常反省自身，少议论他人，是最高级的修养。
The beauty of physics lies in its ability to explain the complex with the simple.
The laws that forbid the carrying of arms are laws of such a nature. They disarm only those who are neither inclined nor determined to commit crimes.... Such laws make things worse for the assaulted and better for the assailants; they serve rather to encourage than to prevent homicides, for an unarmed man may be attacked with greater confidence than an armed man.
Education’s rewards are too distant when today’s survival is urgent.
一棵树的真正价值不在于它的板材体积，而在于它的根系和影响。