As for slavery, there is no need for me to speak of its bad aspects. The only thing requiring explanation is the good side of slavery. I do not mean indirect slavery, the slavery of proletariat; I mean direct slavery, the slavery of the Blacks in Surinam, in Brazil, in the southern regions of North America. Direct slavery is as much the pivot upon which our present-day industrialism turns as are machinery, credit, etc. … Slavery is therefore an economic category of paramount importance.

The ideas of the ruling class are in every epoch the ruling ideas, i.e., the class which is the ruling material force of society, is at the same time its ruling intellectual force.

In the national struggles of the proletarians of the different countries, they point out and bring to the front the common interest of the entire proletariat, independently of all nationality.

In the domain of Political Economy, free scientific inquiry meets not merely the same enemies as in all other domains. The peculiar nature of the material it deals with, summons as foes into the field of battle the most violent, mean and malignant passions of the human breast, the Furies of private interest.

You are horrified at our intending to do away with private property. But in your existing society, private property is already done away with for nine tenths of the population; its existence for the few is solely due to its non-existence in the hands of those nine tenths. You reproach us, therefore, with intending to do away with a form of property, the necessary condition for whose existence is the non-existence of any property for the immense majority of society.

By means of the banking system the distribution of capital as a special business, a social function, is taken out of the hands of the private capitalists and usurers. But at the same time, banking and credit become the most effective means of driving captialist production beyond its own limits and one of the most effective vehicles of crises and swindle.

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