Too much openness and you accept every notion, idea, and hypothesis-which is tantamount to knowing nothing. Too much skepticism-especially rejection of new ideas before they are adequately tested-and you're not only unpleasantly grumpy, but also closed to the advance of science. A judicious mix is what we need.

But down deep, at the molecular heart of life we're essentially identical to trees.

The open road still softly calls, like a nearly forgotten song of childhood

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.

The method of science, as stodgy and grumpy as it may seem, is far more important than the findings of science.

If you are only skeptical, then no new ideas make it through to you. You become a crotchety old person convinced that nonsense is ruling the world. (There is, of course, much data to support you.) But every now and then, a new idea turns out to be on the mark, valid and wonderful. If you are too much in the habit of being skeptical about everything, you are going to miss or resent it, and either way you will be standing in the way of understanding and progress.

If you look at Earth from space you see a dot, that's here. That's home. That's us. It underscores the responsibility to deal more kindly and compassionately with one another and to preserve and cherish that pale blue dot, the only home we've ever known.