We can judge our progress by the courage of our questions and the depth of our answers, our willingness to embrace what is true rather than what feels good.

Cutting off fundamental, curiosity-driven science is like eating the seed corn. We may have a little more to eat next winter but what will we plant so we and our children will have enough to get through the winters to come?

Goddard represented a unique combination of visionary dedication and technological brilliance. He studied physics because he needed physics to get to Mars. In reading the notebooks of Robert Goddard, I am struck by how powerful his exploratory and scientific motivations were - and how influental speculative ideas, even erroneous ones, can be on the shaping of the future.

Accommodation to change, the thoughtful pursuit of alternative futures are keys to the survival of civilization and perhaps of the human species.

Avoidable human misery is more often caused not so much by stupidity as by ignorance, particularly our ignorance about ourselves.

An organism at war with itself is doomed.

There are many hypotheses in physics of almost comparable brillance and elegance that have been rejected because they did not survive such a confrontation with experiment. In my view, the human condition would be greatly improved if such confrontations and willingness to reject hypotheses were a regular part of our social, political, economic, religious and cultural lives.