The history of all previous societies has been the history of class struggles.

The history of all hitherto existing society is the history of class struggles.

Freeman and slave, patrician and plebeian, lord and serf, guildmaster and journeyman, in a word, oppressor and oppressed, stood in constant opposition to one another, carried on an uninterrupted, now hidden, now open fight, that each time ended, either in the revolutionary reconstitution of society at large, or in the common ruin of the contending classes.

Women are the only exploited group in history to have been idealized into powerlessness.

Revolutions are the locomotives of history.

Men [sic] make their own history, but they do not make it as they please; they do not make it under self-selected circumstances, but under circumstances existing already, given and transmitted from the past.

(Marx, 1963)

History always repeats itself twice: first time as tragedy, second time as farce.