There will one day spring from the brain of science a machine or force so fearful in its potentialities, so absolutely terrifying, that even man, the fighter, who will dare torture and death in order to inflict torture and death, will be appalled, and so abandon war forever.

I never view mistakes as failures. They are simply opportunities to find out what doesn't work.

I never did anything by accident, nor did any of my inventions come by accident; they came by work.

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

Be brave as your fathers before you. Have faith and go forward.

Our greatest weakness lies in giving up.

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