Only when creative people take ownership of cosmic discovery will society accept science as the cultural activity that it is.

Something bad happened on both Mars with its dried-up watercourses and Venus with its runaway greenhouse effect. Could something bad happen on Earth too? Our species currently turns row upon row of environmental knobs, without much regard to long-term consequences.

I suppose I can live with missing decimals, missing floors to tall buildings, and floors that are named instead of numbered. A more serious problem is the limited capacity of the human mind to grasp the relative magnitudes of large numbers. Counting at the rate of one number per second...to count to a trillion takes 32,000 years, which is as much time as has elapsed since people first drew on cave walls.

If the Sun exploded, we wouldn't know about it for 8 minutes and 20 seconds. Light and gravity take that long to reach us. Then we would vaporize.

We only went to the moon for military reasons. The space enthusiasts of the day kept saying, "Oh, we're on the moon; we should be on Mars in ten years." That's if it was driven by exploration, but it's never been driven by exploration.

If we have the power to turn another planet into Earth, then we have the power to turn Earth back into Earth.

Just to settle it once and for all: Which came first, the chicken or the egg? The egg, laid by a bird that was not a chicken.