If you have an apple and I have an apple, and we exchange apples, we both still only have one apple. But if you have an idea and I have an idea, and we exchange ideas, we each now have two ideas.
你和我各有一个苹果，如果我们交换苹果的话，我们还是只有一个苹果。但当你和我各有一个想法，我们交换想法的话，我们就都有两个想法了。
一个人的工作不过是通过艺术的迂回，重新发现那两三个伟大而简单的形象，正是它们让他的心初次敞开。
Your attitude, not your aptitude, will determine your altitude.
It seems to me that if you or I must choose between two courses of thought or action, we should remember our dying and try so to live that our death brings no pleasure to the world.
Mathematics is a living subject, constantly evolving and growing.
历史学家必须公正，但不能冷漠。