I believe, indeed, that overemphasis on the purely intellectual attitude, often directed solely to the practical and factual, in our education, has led directly to the impairment of ethical values.

When I examine myself and my methods of thought, I come to the conclusion that the gift of fantasy has meant more to me than any talent for abstract, positive knowledge.

All our thoughts and concepts are called up by sense-experiences and have a meaning only in reference to these sense-experiences. On the other hand, however, they are products of the spontaneous activity of our minds; they are thus in no wise logical consequences of the contents of these sense-experiences. If, therefore, we wish to grasp the essence of a complex of abstract notions we must for the one part investigate the mutual relationships between the concepts and the assertions made about them; for the other, we must investigate how they are related to the experiences.

Any fool can know. The point is to understand.

As far as the laws of mathematics refer to reality, they are not certain, and as far as they are certain, they do not refer to reality.

Before God we are all equally wise - and equally foolish.

By academic freedom I understand the right to search for truth and to publish and teach what one holds to be true. This right implies also a duty: one must not conceal any part of what on has recognized to be true. It is evident that any restriction on academic freedom acts in such a way as to hamper the dissemination of knowledge among the people and thereby impedes national judgment and action.

Common sense is the collection of prejudices acquired by age eighteen.