How selfish soever man may be supposed, there are evidently some principles in his nature, which interest him in the fortune of others, and render their happiness necessary to him, though he derives nothing from it except the pleasure of seeing it.
无论一个人被认为多么自私，他的本性中显然存在某些原则，这些原则使他对别人的命运感兴趣，并将他们的幸福视为自己的必要，尽管他从中除了看到它时的快乐外一无所得。
The more specific you are, the more universal you become.
一本书永远是通往另一个世界的敞开之门。
数学中最令人兴奋的时刻是当你发现两个看似不相关的领域有着深刻的联系。