I find my greatest pleasure, and so my reward, in the work that precedes what the world calls success.

I was always afraid of things that worked the first time. Long experience proved that there were great drawbacks found generally before they could be got commercial; but here was something there was no doubt of.

I am afraid of radium and polonium ... I don't want to monkey with them.

When I have fully decided that a result is worth getting I go ahead of it and make trial after trial until it comes.

Of the 200 light bulbs that didn't work, every failure told me something that I was able to incorporate into the next attempt.

There is no limit to which a man will not go to avoid thinking.

If I had not had so much ambition and not tried to do so many things, I probably would have been happier, but less useful.