Self-criticism, cruel, unsparing criticism that goes to the very root of the evil, is life and breath for the proletarian movement.

With the true artist, the social formula that he recommends is a matter of secondary importance; the source of his art, its animating spirit, is decisive.

We stand todaybefore the awful proposition: either the triumph of imperialism and the destruction of all culture, and, as in ancient Rome, depopulation, desolation, degeneration, a vast cemetery; or, the victory of socialism.

There is no democracy without socialism, and no socialism without democracy.

Those who do not move, do not notice their chains.

Marxism must abhor nothing so much as the possibility that it becomes congealed in its current form. It is at its best when butting heads in self-criticism, and in historical thunder and lightning, it retains its strength.

Only to the rude ear of one who is quite indifferent does the song of a bird seem always the same.