Outside of their particular area of expertise scientists are just as dumb as the next person.

We are at the very beginning of time for the human race. It is not unreasonable that we grapple with problems. But there are tens of thousands of years in the future. Our responsibility is to do what we can, learn what we can, improve the solutions, and pass them on.

There is enough energy in a single cubic meter of space to boil all the oceans in the world.

The highest forms of understanding we can achieve are laughter and human compassion.

We can deduce, often, from one part of physics like the law of gravitation, a principle which turns out to be much more valid than the derivation.

The principle of science, the definition, almost, is the following: The test of all knowledge is experiment. Experiment is the sole judge of scientific "truth." But what is the source of knowledge? Where do the laws that are to be tested come from? Experiment, itself, helps to produce these laws, in the sense that it gives us hints. But also needed is imagination to create from these hints the great generalizations--to guess at the wonderful, simple, but very strange patterns beneath them all, and then to experiment to check again whether we have made the right guess.

Some people think Wheeler's gotten crazy in his later years, but he's always been crazy.