Mathematics is a way of thinking, not just a collection of facts.

文章的妙处在于，一句话能说尽天下的道理，片言能概括万物的情状。

Life is a slope.As long as you're going up you're always looking towards the top and you feel happy, but when you reach it, suddenly you can see the road going downhill and death at the end of it all. It's slow going up and quick going down.

你的20岁是你人生中最重要的十年。