If we can't think for ourselves, if we're unwilling to question authority, then we're just putty in the hands of those in power.

If some good evidence for life after death were announced, I'd be eager to examine it; but it would have to be real scientific data, not mere anecdote. As with the face on Mars and alien abductions, better the hard truth, I say, than the comforting fantasy.

The library connects us with the insight and knowledge, painfully extracted from Nature, of the greatest minds that ever were, with the best teachers, drawn from the entire planet and from all our history, to instruct us without tiring, and to inspire us to make our own contribution to the collective knowledge of the human species.

Our children long for realistic maps of the future that they can be proud of. Where are the cartographers of human purpose?

Atoms are mainly empty space. Matter is composed chiefly of nothing.

A multitude of aspects of the natural world that were considered miraculous only a few generations ago are now thoroughly understood in terms of physics and chemistry.

Eratosthenes was the director of the great library of Alexandria, the Centre of science and learning in the ancient world. Aristotle had argued that humanity was divided into Greeks and everybody else, whom he called barbarians and that the Greeks should keep themselves racially pure. He thought it was fitting for the Greeks to enslave other peoples. But Erathosthenes criticized Aristotle for his blind chauvinism, he believed there was good and bad in every nation.