Science is far from a perfect instrument of knowledge. It's just the best we have.

All inquires carry with them some element of risk. There is no guarantee that the universe will conform to our predispositions.

You could just as well say that an agnostic is a deeply religious person with at least a rudimentary knowledge of human fallibility.

Since, in the long run, every planetary society will be endangered by impacts from space, every surviving civilization is obliged to become spacefaring — not because of exploratory or romantic zeal, but for the most practical reason imaginable: staying alive.

There is today-in a time when old beliefs are withering-a kind of philosophical hunger, a need to know who we are and how we got here. It is an on-going search, often unconscious, for a cosmic perspective for humanity

Extraordinary claim requires extraordinary proof.

The cosmos is within us. We are made of star stuff