It is my conviction that pure mathematical construction enables us to discover the concepts and the laws connecting them, which gives us the key to the understanding of nature ... In a certain sense, therefore, I hold it true that pure thought can grasp reality, as the ancients dreamed.
Nobody knows how the stand of our knowledge about the atom would be without him. Personally, [Niels] Bohr is one of the amiable colleagues I have met. He utters his opinions like one perpetually groping and never like one who believes himself to be in possession of the truth.
[There is] a duty in refusing to cooperate in any undertaking that violates the Constitutional rights of the individual. This holds in particular for all inquisitions that are concerned with the private life and the political affiliations of the citizens.
When men are engaged in war and conquest, the tools of science become as dangerous as a razor in the hands of a child of three. We must not condemn man because his inventiveness and patient conquest of the forces of nature are being exploited for false and destructive purposes. Rather, we should remember that the fate of mankind hinges entirely upon man’s moral development.
When I think of the most able students I have encountered in my teaching - I mean those who have distinguished themselves not only by skill but by independence of thought - then I must confess that all have had a lively interest in epistemology.
I received your letter of June 10th. I have never talked to a Jesuit priest in my life and I am astonished by the audacity to tell such lies about me. From the viewpoint of a Jesuit priest I am, of course, and have always been an atheist.
I could say analogously that tolerance is the affable appreciation of qualities, views, and actions of other individuals which are foreign to one`s own habits, beliefs, and tastes. Thus being tolerant does not mean being indifferent towards the actions and feelings of others. Understanding and empathy must also be present.