When things are going well, something will go wrong. / When things just can't get any worse, they will. / Anytime things appear to be going better, you have overlooked something.

We find that the statements of science are not of what is true and what is not true, but statements of what is known with different degrees of certainty: "It is very much more likely that so and so is true than that it is not true".

There's plenty of room at the bottom.

People often think I'm a faker, but I'm usually honest, in a certain way--in such a way that often nobody believes me!

Turbulence is the most important unsolved problem of classical physics.

We have been led to imagine all sorts of things infinitely more marvelous than the imagining of poets and dreamers of the past. It shows that the imagination of nature is far, far greater than the imagination of man. For instance, how much more remarkable it is for us all to be stuck-half of us upside down-by a mysterious attraction, to a spinning ball that has been swinging in space for billions of years, than to be carried on the back of an elephant supported on a tortoise swimming in a bottomless sea.

It is the fact that the electrons cannot all get on top of each other that makes tables and everything else solid.