How smart does a chimpanzee have to be before killing him constitutes murder?

Scientists can routinely predict a solar eclipse, to the minute, a millennium in advance. You can go to the witch doctor to lift the spell that causes your pernicious anaemia, or you can take Vitamin B12. If you want to save your child from polio, you can pray or you can inoculate. If you're interested in the sex of your unborn child, you can consult plumb-bob danglers all you want . . . but they'll be right, on average, only one time in two. If you want real accuracy . . . try amniocentesis and sonograms. Try science.

In a lot of scientists, the ratio of wonder to skepticism declines in time. That may be connected with the fact that in some fields-mathematics, physics, some others-the great discoveries are almost entirely made by youngsters.

We live in a vast and awesome universe in which, daily, suns are made and worlds destroyed, where humanity clings to an obscure clod of rock.

Time spent with children is time well spent. Their little minds are not constrained by 'reality' or focused upon goals. Anything and everything is possible. Imagination will often carry us to worlds that never were. But without it we go nowhere.

I find science so much more fascinating than science fiction. It also has the advantage of being true.

Exploration is in our nature. We began as wanderers, and we are wanderers still. We have lingered long enough on the shores of the cosmic ocean. We are ready at last to set sail for the stars.