我们所理解的唯一存在就是感知事物的存在。

在数学中，提出问题的艺术必须比解决问题更有价值。

Among thousands of people, you meet those you've met. Through thousands of years, across the boundless wilderness of time, you happen to meet them, neither earlier nor a bit too late. There is nothing to be said except to ask lightly, "Oh, you're here too?"

I like to be different. I don't want to be like everyone else.