The caricature of science is that we hold tight to the theories we have, and shun challenges to them. That's just not true. In fact, we hold our highest rewards for those scientists who can prove others wrong. And by the way, they are famous in their own lifetimes. We don't wait until they're dead.

This influential, yet controversial idea requires that the mixture of species on Earth at any moment acts as a collective organism that continuously (yet unwittingly) tunes Earth's atmospheric composition and climate to promote the presence of life... But I'd bet there are some dead Martians and Venusians who advanced the same theory about their own planets a billion years ago.

We are part of this universe; we are in this universe, but perhaps more important than both of those facts, is that the universe is in us.

I wonder if, in fact, we have been observed by aliens and upon close examination of human conduct and human behavior they have concluded that there is no sign of intelligent life on Earth.

The theory of evolution, like the theory of gravity, is a scientific fact.

I see all this talk about jobs going overseas as a symptom of the absence of innovation. And the absence of innovation is a symptom of there being no major national priority to advance a frontier.

We live in a world where not everyone has the urge to help others... It is OK to encourage others to pull themselves up by the bootstraps, but if you do, just remember that some people have no boots.