It is often claimed that knowledge multiplies so rapidly that nobody can follow it. I believe this is incorrect. At least in science it is not true. The main purpose of science is simplicity and as we understand more things, everything is becoming simpler. This, of course, goes contrary to what everyone accepts.

Really exotic methods of propulsion . . . will have to be devised to get there. How it will be done, I do not know. Whether it will be done, I am not quite certain. But I would bet it can be done.

Society's emissions of carbon dioxide may or may not turn out to have something significant to do with global warming-the jury is still out.

I tried to contribute to the defeat of the Soviets. If I contributed 1%, it is 1% of something enormous.

One may say that predictions are dangerous particularly for the future. If the danger involved in a prediction is not incurred, no consequence follows and the uncertainty principle is not violated.

Physics without mathematics is meaningless.

If there ever was a misnomer, it is "exact science." Science has always been full of mistakes. The present day is no exception. And our mistakes are good mistakes; they require a genius to correct. Of course, we do not see our own mistakes.