In many cultures it is customary to answer that God created the universe out of nothing. But this is mere temporizing. If we wish courageously to pursue the question, we must, of course ask next where God comes from? And if we decide this to be unanswerable, why not save a step and conclude that the universe has always existed?
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.
But, Jefferson worried that the people - and the argument goes back to Thucydides and Aristotle - are easily misled. He also stressed, passionately and repeatedly, that it was essential for the people to understand the risks and benefits of government, to educate themselves, and to involve themselves in the political process. Without that, he said, the wolves will take over.
Writing is perhaps the greatest of human inventions, binding together people who never knew each other, citizens of distant epochs. Books break the shackles of time. A book is proof that humans are capable of magic.
(When asked merely if they accept evolution, 45 percent of Americans say yes. The figure is 70 percent in China.) When the movie Jurassic Park was shown in Israel, it was condemned by some Orthodox rabbis because it accepted evolution and because it taught that dinosaurs lived a hundred million years ago-when, as is plainly stated at every Rosh Hashonhan and every Jewish wedding ceremony, the Universe is less than 6,000 years old.
All of us cherish our beliefs. They are, to a degree, self-defining. When someone comes along who challenges our belief system as insufficiently well-based - or who, like Socrates, merely asks embarrassing questions that we haven't thought of, or demonstrates that we've swept key underlying assumptions under the rug - it becomes much more than a search for knowledge. It feels like a personal assault.
Science is not perfect. It's often misused; it's only a tool, but it's the best tool we have. Self-correcting , ever changing, applicable to everything: with this tool, we vanquish the impossible.
By exploring other worlds we safeguard this one. By itself, I think this fact more than justifies the money our species has spent in sending ships to other worlds. It is our fate to live during one of the most perilous and, at the same time, one of the most hopeful chapters in human history.
The surface of the Earth is the shore of the cosmic ocean. On this shore, we've learned most of what we know. Recently, we've waded a little way out, maybe ankle-deep, and the water seems inviting. Some part of our being knows this is where we came from. We long to return, and we can, because the cosmos is also within us. We're made of star stuff. We are a way for the cosmos to know itself.