The only justification for our concepts and systems of concepts is that they serve to represent the complex of our experiences; beyond this they have not legitimacy.

There is not the slightest indication that nuclear energy will ever be obtainable. It would mean that the atom would have to be shattered at will.

Wisdom is not a product of schooling but of the lifelong attempt to acquire it.

Formerly, people thought that if matter disappeared from the universe, space and time would remain. Relativity declares that space and time would disappear with matter.

An expert is a person who has few new ideas; a beginner is a person with many.

It may affront the military-minded person to suggest a regime that does not maintain any military secrets.

The world is an evil place to live in. Not for those who do evil, but for those who sit back and allow evil to occur.