The stranger is close to us, insofar as we feel between him and ourselves common features of a national, social, occupational, or generally human, nature. He is far from us, insofar as these common features extend beyond him or us, and connect us only because they connect a great many people.

To live is the rarest thing in the world. Most people exist, that is all.

You are as big as the things that make you angry.

我们都害怕——为我们的信心，为未来，为这个世界。

"In observational studies, we often have to rely on assumptions that are not directly testable."

On pivoting: "If you're not stubborn， you'll give up on experiments too soon. And if you're not flexible， you'll pound your head against the wall and you won't see a different solution to a problem you're trying to solve."

All my life through, the new sights of Nature made me rejoice like a child.

If you're alive, you've got to flap your arms and legs, you've got to jump around a lot, you've got to make a lot of noise, because life is the very opposite of death.