Without general elections, without unrestricted freedom of press and assembly, without a free struggle of opinion, life dies out in every public inst….

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

The high stage of world-industrial development in capitalistic production finds expression in the extraordinary technical development and destructive….

The more that social democracy develops, grows, and becomes stronger, the more the enlightened masses of workers will take their own destinies, the l….

History is the only true teacher, the revolution the best school for the proletariat..

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-cri….

Revolutionary tactics cannot be invented by leaders; they must develop spontaneously-history comes first, leaders' consciousness second..

The masses are the decisive element, they are the rock on which the final victory of the revolution will be built..

We will be victorious if we have not forgotten how to learn..

The victory of socialism will not descend like fate from heaven..

The working classes in every country only learn to fight in the course of their struggles..

The clergy, no less than the capitalist class, lives on the backs of the people, profits from the degradation, the ignorance and the oppression of th….

What do you want with these special Jewish pains? I feel as close to the wretched victims of the rubber plantations in Putamayo and the blacks of Afr….

We stand todaybefore the awful proposition: either the triumph of imperialism and the destruction of all culture, and, as in ancient Rome, depopulati….

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

Freedom only for the members of the government, only for the members of the Party - though they are quite numerous - is no freedom at all..

Those who don't move don't notice their chains..

Life is singing also in the sand crunching under the slow and heavy steps of the guards, when we know how to listen to it..

Only through the conscious action of the working masses in city and country can it be brought to life, only through the people's highest intellectual….

The working classes in every country only learn to fight in the course of their struggles...Social democracy...is only the advance guard of the prole….

The self-discipline of the Social Democracy is not merely the replacement of the authority of bourgeois rulers with the authority of a socialist cent….