Poetry is the mirror of the soul.

在观察性研究中，我们常常不得不依赖于无法直接检验的假设。

International politics is a ruthless and dangerous business, and it is foolish to expect states to behave according to moral principles.

There are some people who think love is marriage and six o'clock-kisses and children, and perhaps it is, Miss Lester. But do you know what I think? I think love is a touch and yet not a touch.

Don’t wait for the perfect moment; take the moment and make it perfect.

从精神奴役中解放自己，只有我们自己才能解放我们的思想。

The best illustrations are those that leave room for the reader's imagination.