We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology.

We can judge our progress by the courage of our questions and the depth of our answers, our willingness to embrace what is true rather than what feels good.

We have begun to contemplate our origins: starstuff pondering the stars; organized assemblages of ten billion billion billion atoms considering the evolution of atoms; tracing the long journey by which, here at least, consciousness arose.

Science is a collaborative enterprise, spanning the generations. When it permits us to see the far side of some new horizon, we remember those who prepared the way - seeing for them also.

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

Many religions have attempted to make statues of their gods very large, and the idea, I suppose, is to make us feel small. But if that's their purpose, they can keep their paltry icons. We need only look up if we wish to feel small.

The significance of our lives and our fragile planet is then determined only by our own wisdom and courage. We are the custodians of life's meaning. We long for a Parent to care for us, to forgive us our errors, to save us from our childish mistakes. But knowledge is preferable to ignorance. Better by far to embrace the hard truth than a reassuring fable. If we crave some cosmic purpose, then let us find ourselves a worthy goal.