Quality is not an act, it is a habit.

The world is full of small pleasures; the trick is to find them.

The true teacher defends his pupils against his own personal influence. He inspires self-distrust. He guides their eyes from himself to the spirit that quickens him. He will have no disciple.

数学的美在于它让我们看到世界上不立即显现的模式和结构。

为自己的原则而战比实践这些原则要容易。

La literatura no sirve para nada, y por eso es imprescindible.

解释：兄弟之间虽然会因谗言而起争执，但在遇到外人的侮辱时仍应一致对外。