I never knew I had an inventive talent until Phrenology told me so. I was a stranger to myself until then!

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

The three things that are most essential to achievement are common sense, hard work and stick-to-it-iv-ness.

The money one gets for selling one's soul is always spent in deadening one's conscience, so the net gain at the end of a lifetime is no greater than if the diabolic bargain had not been struck.

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.

Every wrong attempt discarded is another step forward

Nothing that's good works by itself, you've got to make the damn thing work.