If you look at the history of unexplained phenomena that was first explained by spiritual, mystical forces, the track record is not very good for the mystical, magical explanations to survive against more quote "mundane" physical explanations.

When your reasons for believing something are justified ad hoc, you are left susceptible to further discoveries undermining the rationale for that belief.

Santa knows Physics: Of all colors, Red Light penetrates fog best. That's why Benny the Blue-nosed reindeer never got the gig.

Publicly and among themselves biologists rightly celebrate the diversity of life on Earth... At the end of the day, however, their confession is heard by no one: they work with a single scientific sample-life on Earth.

Asteroids have us in our sight. The dinosaurs didn't have a space program, so they're not here to talk about this problem. We are, and we have the power to do something about it. I don't want to be the embarrassment of the galaxy, to have had the power to deflect an asteroid, and then not, and end up going extinct.

Do you realize that the 850 billion dollar bank bailout, that sum of money is greater than the entire 50 year running budget of NASA. And so when someone says, 'We don't have enough money for this space probe.' No, it's not that you don't have enough money. It's that the distribution of money that you're spending is warped in some way that you are removing the only thing that gives people something to dream about tomorrow.

Who you are, where you've been and what you've done is all up here, captured and preserved in your memories. If you lost that - the story of your own origins - you'd lose your identity, your sense of self.