把这一句，留给此刻的你

We often think that when we have completed our study of one we know all about two, because "two" is "one and one." We forget that we still have to make a study of "and."

我们常常认为，当我们完成了对一的学习，我们就知道了关于二的一切，因为“二”就是“一和一”。我们忘记了我们仍然要研究“和”。

— Arthur Eddington 爱丁顿