The experience of the irrationality of the world has been the driving force of all religious revolution.

Within the confines of the lecture hall, no other virtue exists but plain intellectual integrity.

Only he has the calling for politics who is sure that he shall not crumble when the world from his point of view is too stupid or too base for what he wants to offer. Only he who in the face of all this can say 'In spite of all!' has the calling for politics.

Only by strict specialization can the scientific worker become fully conscious, for once and perhaps never again in his lifetime, that he has achieved something that will endure. A really definitive and good accomplishment is today always a specialized act.

Daily and hourly, the politician inwardly has to overcome a quite trivial and all-too-human enemy: a quite vulgar vanity.

Either one lives for politics or one lives off politics.

The so-called materialistic conception of history, with the crude elements of genius of the early form which appeared, for instance, in the Communist Manifesto, still prevails only in the minds of laymen and dilettantes.