If our solar system is not unusual, then there are so many planets in the universe that, for example, they outnumber the sum of all sounds and words ever uttered by every human who has ever lived. To declare that Earth must be the only planet with life in the universe would be inexcusably bigheaded of us.

I wake up and I go to work. I don't look for the cup of coffee. The universe is enough of a draw for me - to awaken me and have me bound out of bed and go to my office.

Kids are born curious about the world. What adults primarily do in the presence of kids is unwittingly thwart the curiosity of children.

If you love what you do, you'll be your best at it compared to anything else you might have chosen as a career. Or at least you will love it more, and you won't lead a depressed day of your life.

The remarkable feature of physical laws is that they apply everywhere, whether or not you choose to believe in them. After the laws of physics, everything else is opinion.

Claiming there is no other life in the universe is like scooping up some water, looking at the cup and claiming there are no whales in the ocean.

I can't think that leaving Earth once is enough.