It is astonishing what an effort it seems to be for many people to put their brains definitely and systematically to work.

I have a peculiar theory about radium, and I believe it is the correct one. I believe that there is some mysterious ray pervading the universe that is fluorescing to it. In other words, that all its energy is not self-constructed but that there is a mysterious something in the atmosphere that scientists have not found that is drawing out those infinitesimal atoms and distributing them forcefully and indestructibly.

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.

I am so deaf I am debarred from hearing all the time articulation and have to depend on the judgment of others.

What a man's mind can create, man's character can control.

Most of my ideas belonged to other people who never bothered to develop them.

Genius is not inspired. Inspiration is perspiration.