If quantum mechanics hasn't profoundly shocked you, you haven't understood it yet.

It is, indeed, perhaps the greatest prospect of humanistic studies to contribute through an increasing knowledge of the history of cultural development to that gradual removal of prejudices which is the common aim of all science.

In our description of nature the purpose is not to disclose the real essence of the phenomena but only to track down, so far as it is possible, relations between the manifold aspects of our experience.

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 and establishing mental connections.

Truth and clarity are complementary.

Opposites are not contradictory but complementary.

It is the hallmark of any deep truth that its negation is also a deep truth.