Utopias have their value -- nothing so wonderfully expands the imaginative horizons of human potentialities -- but as guides to conduct they can prove literally fatal.

The notion of the perfect whole, the ultimate solution in which all good things coexist, seems to me not merely unobtainable--that is a truism--but conceptually incoherent. ......Some among the great goods cannot live together. That is a conceptual truth. We are doomed to choose, and every choice may entail an irreparable loss.

No perfect solution is, not merely in practice, but in principle, possible in human affairs, and any determined attempt to produce it is likely to lead to suffering, disillusionment and failure.

Science cannot destroy the consciousness of freedom, without which there is no morality and no art, but it can refute it.

The very desire for guarantees that our values are eternal and secure in some objective heaven is perhaps only a craving for the certainties of childhood or the absolute values of our primitive past.

Lenin could listen so intently that he exhausted the speaker.

The most passionate, consistent, extreme and implacable enemy of the Enlightenment and ... all forms of rationalism ... was Johann Georg Hamann. His influence, direct and indirect, upon the romantic revolt against universalism and scientific method ... was considerable and perhaps crucial.