地球在所有方向上都是相同的，人类在任何地方都直立其上。

I got the idea to start Amazon 16 years ago. I came across the fact that Web usage was growing at 2，300 percent per year. I'd never seen or heard of anything that grew that fast， and the idea of building an online bookstore with millions of titles -- something that simply couldn't exist in the physical world -- was very exciting to me. I had just turned 30 years old， and I'd been married for a year. I told my wife MacKenzie that I wanted to quit my job and go do this crazy thing that probably wouldn't work since most startups don't， and I wasn't sure what would happen after that. MacKenzie (also a Princeton grad and sitting here in the second row) told me I should go for it. As a young boy， I'd been a garage inventor. I'd invented an automatic gate closer out of cement-filled tires， a solar cooker that didn't work very well out of an umbrella and tinfoil， baking-pan alarms to entrap my siblings. I'd always wanted to be an inventor， and she wanted me to follow my passion.

我不怕死，我怕不去尝试。

Parental investment is the key to understanding sex differences in mating strategies.

理解计算的极限与扩展其能力同样重要。