[Kepler] preferred the hard truth to his dearest illusions, and that is the heart of science.

We are the children equally of the Sky and the Earth.

The visions we offer our children shape the future.

I can find in my undergraduate classes, bright students who do not know that the stars rise and set at night, or even that the Sun is a star.

We are rare and precious because we are alive, because we can think as well as we can. We are privileged to influence and perhaps control our future. I believe we have an obligation to fight for life on Earth - not just for ourselves, but for all those, humans and others, who came before us, and to whom we are beholden, and for all those who, if we are wise enough, will come after.

The difference between physics and metaphysics is not that the practitioners of one are smarter than the practitioners of the other. The difference is that the metaphysicist has no laboratory.

Human history can be viewed as a slowly dawning awareness that we are members of a larger group Groups of people from divergent ethnic and cultural backgrounds working in some sense together [is] surely a humanizing and character building experience. If we are to survive, our loyalties must be broadened further, to include the whole human community, the entire planet Earth.