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.

The United States, and other advanced nations, will someday be able to produce instruments of death so terrible the world will be in abject terror of itself and its ability to end civilization.... Such war-making weapons should be developed - but only for purposes of discovery and experimentation

There seems to be no limit to which some men will go to avoid the labor of thinking. Thinking is hard work.

Nature made us - nature did it all - not the gods of the religions.

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

I consider Paine our greatest political thinker. As we have not advanced, and perhaps never shall advance, beyond the Declaration and Constitution, so Paine has had no successors who extended his principles.

The value of a good idea is in using it.