At that age， I'd take any excuse to make estimates and do minor arithmetic. I'd calculate our gas mileage -- figure out useless statistics on things like grocery spending. I'd been hearing an ad campaign about smoking. I can't remember the details， but basically the ad said， every puff of a cigarette takes some number of minutes off of your life: I think it might have been two minutes per puff. At any rate， I decided to do the math for my grandmother. I estimated the number of cigarettes per days， estimated the number of puffs per cigarette and so on. When I was satisfied that I'd come up with a reasonable number， I poked my head into the front of the car， tapped my grandmother on the shoulder， and proudly proclaimed， "At two minutes per puff， you've taken nine years off your life！"

Polka dots can't stay alone, like human existence.

最大的智慧是知道自己一无所知。

The essence of creativity is figuring out how to use what you already know in order to go beyond what you already think.

老师声称代数是完美而自然的、我们应无条件地接受它，而我甚至不能理解什么是数。对我来说数学课完全就是恐怖和折磨。我完全不理解代数，这使我胆怯得不敢问任何问题。

The fact that there is nothing permanent except change is a permanent theme in nature.

每一本书都是一次旅程，而每一次旅程都是一本书。