“Anyone who can contemplate quantum mechanics without getting dizzy hasn’t understood it.”

It is a great pity that human beings cannot find all of their satisfaction in scientific contemplativeness.

There are two sorts of truth: trivialities, where opposites are clearly absurd, and profound truths, recognised by the fact that the opposite is also a profound truth.

If an idea does not appear bizarre, there is no hope for it.

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

Address to Albert Einstein: You are not thinking. You are merely being logical.

When it comes to atoms, language can be used only as in poetry.

There are some things so serious you have to laugh at them.

One must always do what one really cannot.

There is no hope for any speculation that does not look absurd at first glance.

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

If anybody says he can think about quantum physics without getting giddy, that only shows he has not understood the first thing about them.

If we couldn’t laugh at ourselves, that would be the end of everything.

An expert is a man who has made all the mistakes which can be made, in a narrow field.

Physics is the belief that a simple and consistent description of nature is possible.

Some subjects are so serious that one can only joke about them.

Sometimes the child in one behaves a certain way and the rest of oneself follows behind, slowly shaking its head.

Magnetic lines of force convey a far better and purer idea than the phrase magnetic current or magnetic flood: it avoids the assumption of a current or of two currents and also of fluids or a fluid, yet conveys a full and useful pictorial idea to the mind.

No paradox, no progress.

Speculations? I have none. I am resting on certainties.

Democracy is the art and science of running the circus from the monkey cage.

The lasting pleasures of contact with the natural world are not reserved for scientists but are available to anyone who will place himself under the influence of earth, sea and sky and their amazing life.

There is one quality that characterizes all of us who deal with the sciences of the earth and its life – we are never bored.

Opposites are not contradictory but complementary.

The aim of science is to discover and illuminate truth. And that, I take it, is the aim of literature, whether biography or history or fiction. It seems to me, then, that there can be no separate literature of science.