Our greatest weakness lies in giving up. The most certain way to succeed is always to try just one more time.
The purpose of abstraction is not to be vague, but to create a new semantic level in which one can be absolutely precise.
If you're not failing occasionally, you're not pushing hard enough.
一个好的系统设计是使做正确的事情变得容易,做错误的事情变得困难。