睹貌而相悦者，人之情也。
解释：看见美丽的容貌就心悦，是人之常情。
When you are young, you think you will be happy when you are older. But then you get older and you realize you were happy when you were young.
学习各种思维模型是你能给自己最好的礼物。
定义就是限制。