The hardest single part of building a software system is deciding precisely what to build.

Most people are afraid of change, but if you look at it like it's something that can always count on, then it can be a comfort．It doesn't have many things that you can count on．

The city is the greatest invention of mankind.

科学不仅仅是关于发现，而是关于理解我们所发现的东西的含义。

世界可能是残酷的，但它也是美丽的。