“I am nothing but I must be everything.”

“If anything is certain, it is that I myself am not a Marxist.[In a letter about the peculiar 'Marxism' which arose in France 1882]”

“Your favourite virtue ... SimplicityYour favourite virtue in man ... StrengthYour favourite virtue in woman ... WeaknessYour chief characteristic ... Singleness of purposeYour idea of happiness ... To fightYour idea of misery ... SubmissionThe vice you excuse most ... GullibilityThe vice you detest most ... ServilityYour aversion ... Martin TupperFavourite occupation ... Book-wormingFavourite poet ... Shakespeare, Aeschylus, GoetheFavourite prose-writer ... DiderotFavourite hero ... Spartacus, KeplerFavourite heroine ... Gretchen [Heroine of Goethe's Faust]Favourite flower ... DaphneFavourite colour ... RedFavourite name ... Laura, JennyFavourite dish ... FishFavourite maxim ... Nihil humani a me alienum puto [Nothing human is alien to me]Favourite motto ... De omnibus dubitandum [Everything must be doubted].”

“...it is all the more clear what we have to accomplish at present: I am referring to ruthless criticism of all that exists, ruthless both in the sense of not being afraid of the results it arrives at and in the sense of being just as little afraid of conflict with the powers that be.”

“You must be aware that the reward for labour, and quantity of labour, are quite disparate things.”

“The proletarians have nothing to loose but their chains. They have a world to win.”

“Let the ruling classes tremble at a Communistic revolution. The proletarians have nothing to lose but their chains. They have a world to win.Workingmen of all countries unite!”