Invention is 1% inspiration and 99% perspiration

I am much less interested in what is called God's word than in God's deeds. All bibles are man-made.

X-rays ... I am afraid of them. I stopped experimenting with them two years ago, when I came near to losing my eyesight and Dally, my assistant practically lost the use of both of his arms.

To those searching for truth -- not the truth of dogma and darkness but the truth brought by reason, search, examination, and inquiry, discipline is required. For faith, as well intentioned as it may be, must be built on facts, not fiction -- faith in fiction is a damnable false hope.

I remember that I was never able to get along at school. I was at the foot of the class.

I am proud of the fact that I never invented weapons to kill.

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