Teller contended, not implausibly, that hydrogen bombs keep the peace, or at least prevent thermonuclear war, because the consequences of warfare between nuclear powers are now too dangerous. We haven't had a nuclear war yet, have we? But all such arguments assume that the nuclear-armed nations are and always will be, without exception, rational actors, and that bouts of anger and revenge and madness will never overtake their leaders (or military and secret police officers in charge of nuclear weapons). In the century of Hitler and Stalin, this seems ingenuous.

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

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.

Societies will, of course, wish to exercise prudence in deciding which technologies that is, which applications of science are to be pursued and which not. But without funding basic research, without supporting the acquisition of knowledge for its own sake, our options become dangerously limited.

This oak tree and me, we're made of the same stuff.

We have heard the rationales offered by the nuclear superpowers. We know who speaks for the nations. But who speaks for the human species? Who speaks for Earth?

The suppression of uncomfortable ideas may be common in religion or in politics, but it is not the path to knowledge, and there's no place for it in the endeavor of science. We do not know beforehand where fundamental insights will arise from about our mysterious and lovely solar system. The history of our study of our solar system shows us clearly that accepted and conventional ideas are often wrong, and that fundamental insights can arise from the most unexpected sources.