Thomas Jefferson basically secularized Jesus.

If an alien lands on your front lawn and extends an appendage as a gesture of greeting, before you get friendly, toss it an eightball. If the appendage explodes, then the alien was probably made of antimatter. If not, then you can proceed to take it to your leader.

Space exploration is a force of nature unto itself that no other force in society can rival.

FM signals and those of broadcast television...travel out to space at the speed of light. Any eavesdropping alien civilization will know all about our TV programs (probably a bad thing), will hear all our FM music (probably a good thing), and know nothing of the politics of AM talk-show hosts (probably a safe thing).

I want to create the airplane that flies in the rarified atmosphere of Mars. This is what galvanizes a generation to want to become scientists and engineers in the first place, not we need a scientist to develop a plane that's 20 percent more fuel-efficient than the one your parents flew.

I have found that when calculating what no one has calculated before, like my observing sessions on the mountain, my mental acuity peaks. Ironically, these are the times that I would flunk the reality check normally reserved for mental patients and dazed boxers: What is your name? What day is it? Who is the president of the United States?... I do not know, and I do not care. I am at peace with my equations as I connect to the cosmic engines that drive our universe.

You say you're worried about kids? I'm not worried about kids, I'm worried about grown ups... Children are not the problem here... We spend the first year of their lives teaching them how to walk and talk, and the rest of their lives telling them to shut up and sit down.