Knowledge is not a loose-leaf notebook of facts. Above all, it is a responsibility for the integrity of what we are, primarily of what we are as ethical creatures.

It is important that students bring a certain ragamuffin, barefoot irreverence to their studies; they are not here to worship what is known, but to question it.

No science is immune to the infection of politics and the corruption of power.

Ask an impertinent question and you are on the way to the pertinent answer.

Man is unique not because he does science, and his is unique not because he does art, but because science and art equally are expressions of his marvelous plasticity of mind.

Knowledge is an unending adventure at the edge of uncertainty.

The hand is the cutting edge of the mind.

We have to understand that the world can only be grasped by action, not by contemplation. The hand is more important than the eye ... The hand is the cutting edge of the mind.

Man masters nature not by force, but by understanding

Dissent is the mark of freedom.

One aim of physical sciences had been to give an exact picture the material world. One achievement of physics in the twentieth century has been to prove that that aim is unattainable.

Stray cats are like two-timing men. He got tired of you and took off. He doesn't find anyone new? He'll come slinking back. By then, if you're smart, you'll have decided you're better without him.

You cannot advance if you cannot visualize the end from the start.

It occurs to me that with all the television people watch, most of their acquaintances are actors.

Unless I write every day, I don't feel I deserve my dinner.

When I found the beautiful white bones in the desert I picked them up and took them home too...I have used these things to say what is to me the wideness and wonder of the world as I live in it.

If you don't fill your days with love, you are wasting your life.

Politeness is the result of good sense and good nature.

Writing is mainly perspiration, not inspiration.

Definition is the companion of clarity; clarity is the guide to your goals.

No one ever keeps a secret so well as a child.