Frederick Douglas taught that literacy is the path from slavery to freedom. There are many kinds of slavery and many kinds of freedom, but reading is still the path.

Think of how many religions attempt to validate themselves with prophecy. Think of how many people rely on these prophecies, however vague, however unfulfilled, to support or prop up their beliefs. Yet has there ever been a religion with the prophetic accuracy and reliability of science? ... No other human institution comes close.

The brain is like a muscle. When it is in use we feel very good. Understanding is joyous.

An atheist is someone who is certain that God does not exist, someone who has compelling evidence against the existence of God. I know of no such compelling evidence.

In exchange for freedom of inquiry, scientists are obliged to explain their work.

National boundaries are not evident when we view the Earth from space. Fanatical ethnic or religious or national chauvinisms are a little difficult to maintain when we see our planet as a fragile blue crescent fading to become an inconspicuous point of light against the bastion and citadel of the stars.

We are prodding, challenging, seeking contradictions or small, persistent residual errors, proposing alternative explanations, encouraging heresy. We give our highest rewards to those who convincingly disprove established beliefs.