I cannot believe in the immortality of the soul. No, all this talk of an existence for us, as individuals, beyond the grave is wrong. It is born of our tenacity of life - our desire to go on living - our dread of coming to an end.

Our greatest weakness lies in giving up.

Ideas without execution are hallucinations.

IF PARENTS PASS ENTHUSIASM ALONG TO THEIR CHILDREN, THEY WILL LEAVE THEM AN ESTATE OF INCALCULABLE VALUE

When I have eliminated the ways that will not work, I will find the way that will work.

Good fortune is what happens when opportunity meets with planning.

I make more mistakes than anyone else I know, and sooner or later, I patent most of them.