I write to discover what I think. After all, the bars aren't open that early.

The computer can help us find what we know is there. But the book remains our symbol and our resource for the unimagined question and the unwelcome answer.

Water, that wonderful, flowing medium, the luck of the planet - which would serve humankind in so many ways, and which would give our planet a special character.

The most promising words ever written on the maps of human knowledge are terra incognita, unknown territory.

The most important lesson of American history is the promise of the unexpected. None of our ancestors would have imagined settling way over here on this unknown continent. So we must continue to have society that is hospitable to the unexpected, which allows possibilities to develop beyond our own imaginings.

I have observed that the world has suffered far less from ignorance than from pretensions to knowledge. It is not skeptics or explorers but fanatics and ideologues who menace decency and progress. No agnostic ever burned anyone at the stake or tortured a pagan, a heretic, or an unbeliever.

The hero was distinguished by his achievement; the celebrity by his name or trademark.