The writer must earn money in order to be able to live and to write, but he must by no means live and write for the purpose of making money.

Once the inner connection is grasped, all theoretical belief in the permanent necessity of existing conditions collapses before their collapse in practice -- Letter to Ludwig Kugelmann (July 11, 1868)

Bourgeois society ought long ago to have gone to the dogs through sheer idleness; for those of its members who work, acquire nothing, and those who acquire anything, do not work.

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

Without the presence of class warfare, trade unions would be hard put to justfy their existence.

...the realm of freedom does not commence until the point is passed where labor under the compulsion of necessity and of external utility is required.

Anyone who knows anything of history knows that great social changes are impossible without feminine upheaval. Social progress can be measured exactly by the social position of the fair sex, the ugly ones included.