I have not failed. I've just found 10,000 foundations and individual donors whose priorities don't align with my organization's.

Keep on the lookout for novel ideas that others have used successfully. Your idea has to be original only in its adaptation to the problem you're working on.

The three things that are most essential to achievement are common sense, hard work and stick-to-it-iv-ness... Unfortunately, many of life's failures are experienced by people who did not realize how close they were to success when they gave up. I have far more respect for the person with a single idea who gets there than for the person with a thousand ideas who does nothing.

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 would construct and work along various lines until I found them untenable. When one theory was discarded, I developed another at once. I realized very early that this was the only possible way for me to work out all the problems.

When there's no experimenting there's no progress. Stop experimenting and you go backward. If anything goes wrong, experiment until you get to the very bottom of the trouble.

Radio is just a fashion contrivance that will soon die out. It is obvious that there never will be invented a proper receiver!