We can make a similar examination, but with greater uncertainty, of the extraterrestrial hypothesis that holds that a wide range of UFOs viewed on the planet Earth are space vehicles from planets of other stars.

Science is much more than a body of knowledge. It is a way of thinking. This is central to its success. Science invites us to let the facts in, even when they don't conform to our preconceptions. It counsels us to carry alternative hypotheses in our heads and see which ones best match the facts. It urges on us a fine balance between no-holds-barred openness to new ideas, however heretical, and the most rigorous skeptical scrutiny of everything - new ideas and established wisdom.

The cure for a fallacious argument is a better argument, not the suppression of ideas.

Religions are tough. Either they make no contentions which are subject to disproof or they quickly redesign doctrine after disproof. ... near the core of the religious experience is something remarkably resistant to rational inquiry.

Science cuts two ways, of course; its products can be used for both good and evil. But there's no turning back from science. The early warnings about technological dangers also come from science.

The universe is not required to be in perfect harmony with human ambition.

All of the books in the world contain no more information than is broadcast as video in a single large American city in a single year. Not all bits have equal value.