A reporter called on Edison to interview him about a substitute for lead in the manufacture of storage batteries that the scientist was seeking. Edison informed the man that he had made 20,000 experiments but none had worked. "Aren't you discouraged by all this waste of effort?" the reporter asked. Edison: "Waste! There's nothing wasted. I have discovered 20,000 things that won't work."

I have not failed 700 times. I have not failed once. I have succeeded in proving that those 700 ways will not work. When I have eliminated the ways that will not work, I will find the way that will work.

Consider data without prejudice.

Restlessness is discontent and discontent is the first necessity of progress. Show me a thoroughly satisfied man and I will show you a failure.

Somewhere between the ages of eleven and fifteen, the average child begins to suffer from an atrophy, the paralysis of curiosity and the suspension of the power to observe. The trouble, I should judge, to lie with the schools.

Youth doesn't take advice.

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