The past is not dead. It is not even past.

Quality is free. It's not a gift, but it's free. What costs money are the unquality things -- all the actions that involve not doing jobs right the first time.

我们不是朋克乐队，我们不是流行乐队，我们是U2。

"The world is full of magic things, patiently waiting for our senses to grow sharper."

Randomized evaluations can help us understand what works and what doesn't in development.

I’m stronger than I thought I was.

你最不满意的客户是你最大的学习来源。