The power of abstraction allows us to see the common threads that run through seemingly disparate problems.
我不得不提醒自己,有些鸟是不能关在笼子里的,他们的羽毛太漂亮了,当他们飞走的时候…你会觉得把他们关起来是种罪恶,但是,他们不在了你会感到寂寞,可是我只是想我的朋友了…
A proof of a proposition is a process the nature of which is such as to produce in us a belief in that proposition.