History is not just the story of bad people doing bad things. It's also the story of good people doing nothing.

The best way to cheer yourself up is to try to cheer somebody else up.

In mathematics, the journey is as important as the destination.

一年中的夜晚与白天数量相同、持续时间一样长。即使快乐的生活也有其阴暗笔触，没有“悲哀”提供平衡，“愉快”一词就会失去意义。耐心镇静地接受世事变迁，是最好的处事之道。