Human history can be viewed as a slowly dawning awareness that we are members of a larger group.

I consider it an extremely dangerous doctrine, because the more likely we are to assume that the solution comes from the outside, the less likely we are to solve our problems ourselves.

To live in the hearts of others is to never die in those we leave behind.

[One's] inability to invalidate your hypothesis is not at all the same thing as proving it true.

There is perhaps no better a demonstration of the folly of human conceits than this distant image of our tiny world.

The total number of stars in the Universe is larger than all the grains of sand on all the beaches of the planet Earth.

Our ancestors lived out of doors. They were as familiar with the night sky as most of us are with our favorite television programs.