To invent, you need a good imagination and a pile of junk.

The inventor can't do it all, you've got to change people. We have an enormous capacity to invent super-machinery. But our desire to install the device is weak. Human inertia is the problem, not invention. Something in man makes him resist change.

Be brave as your fathers before you. Have faith and go forward.

Many a person who could not comprehend Rousseau, and would be puzzled by Montesquieu, could understand Paine as an open book. He wrote with a clarity, a sharpness of outline and exactness of speech that even a schoolboy should be able to grasp.

I've never made a mistake. I've only learned from experience.

It is very beautiful over there. (last words)

The most necessary task of civilization is to teach people how to think. It should be the primary purpose of our public schools. The mind of a child is naturally active, it develops through exercise. Give a child plenty of exercise, for body and brain. The trouble with our way of educating is that it does not give elasticity to the mind. It casts the brain into a mold. It insists that the child must accept. It does not encourage original thought or reasoning, and it lays more stress on memory than observation.