One can say that three pre-eminent qualities are decisive for the politician: passion, a feeling of responsibility, and a sense of proportion.

Man does not by nature wish to earn more and more money.

Puritanism carried the ethos of the rational organization of capital and labor. It took over from the Jewish ethic only what was adapted to this purpose.

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.

One cannot with impunity try to transfer this task entirely to mechanical assistants if one wishes to figure something, even though the final result is often small indeed.

The nation is burdened with the heavy curse on those who come afterwards. The generation before us was inspired by an activism and a naive enthusiasm, which we cannot rekindle, because we confront tasks of a different kind from those which our fathers faced.

[In] the realm of science, ... what we have achieved will be obsolete in ten, twenty or fifty years. That is the fate, indeed, that is the very meaning of scientific work. ... Every scientific "fulfillment" raises new "questions" and cries out to be surpassed rendered obsolete. Everyone who wishes to serve science has to resign himself to this.