To the scientist, the universality of physical laws makes the cosmos a marvelously simple place. By comparison, human nature-the psychologist's domain-is infinitely more daunting.

All tweets are tasty. Any tweet anybody writes is tasty. So, I try to have each tweet not simply be informative, but have some outlook, some perspective that you might not otherwise had.

Practically every food you buy in a store for consumption by humans is genetically modified food. There are no wild, seedless watermelons. There’s no wild cows.

Long ago Mars was an oasis of running water.Today the Martiansurfaceis a sterile,barren desert. Here on Earth, who knows what climactic knobs we unwittingly turn,which might one day render Earth as dry and lifeless as Mars. (From the cover of Old Poison by Joan Francis)

Curiosity is a self-driven motivation to explore and to learn. Learning is like... you know, you have to take your medicine. And that is what it has become. And that's unfortunate.

The great tragedy is that they're removing art completely, not because they're putting more science in, but because they can't afford the art teachers or because somebody thinks it's not useful. An enlightened society has all of this going on within it. It's part of what distinguishes what it is to be human from other life forms on Earth - that we have culture.

I've always been interested in pop culture. Some of my colleagues think of pop culture as beneath them, or there's the ivory tower and then there's everybody else, and I never could buy into that wall that's been put up by so many people over the decades and even the centuries.