Your theory is crazy, but it's not crazy enough to be true.

Prediction is very difficult, especially if it's about the future.

Every great and deep difficulty bears in itself its own solution. It forces us to change our thinking in order to find it.

Technology has advanced more in the last thirty years than in the previous two thousand. The exponential increase in advancement will only continue.

While the finish given to our picture of the world by the theory of relativity has already been absorbed into the general scientific consciousness, this has scarcely occurred to the same extent with those aspects of the general problem of knowledge which have been elucidated by the quantum theory.

When it comes to atoms, language can be used only as in poetry. The poet, too, is not nearly so concerned with describing facts as with creating images.

The opposite of a fact is falsehood, but the opposite of one profound truth may very well be another profound truth.

How wonderful that we have met with a paradox. Now we have some hope of making progress.