An extraterrestrial being, newly arrived on Earth - scrutinizing what we mainly present to our children in television, radio, movies, newspapers, magazines, the comics, and many books - might easily conclude that we are intent on teaching them murder, rape, cruelty, superstition, credulity, and consumerism. We keep at it, and through constant repetition many of them finally get it.

We are an intelligent species and the use of our intelligence quite properly gives us pleasure. In this respect the brain is like a muscle. When we think well, we feel good. Understanding is a kind of ecstasy.

Those afraid of the universe as it really is, those who pretend to nonexistent knowledge and envision a Cosmos centered on human beings will prefer the fleeting comforts of superstition.

We are not smart enough to decide which pieces of knowledge are permissible and which are not.

At a few hundred kilometers altitude, the Earth fills half your sky, and the band of blue that stretches from Mindanao to Bombay, which your eye encompasses in a single glance, can break your heart with its beauty. Home you think. Home. This is my world. This is where I come from. Everyone I know, everyone I ever heard of, grew up down there, under that relentless and exquisite blue.

If intelligence is our only edge, we must learn to use it better, to shape it, to understand its limitations and deficiencies -- to use it as cats use stealth, as katydids use camouflage -- to make it the tool of our survival.

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