Religion is the opium of the people.
Philosophers have only interpreted the world in various ways; the point, however, is to change it.
Reason has always existed, but not always in a reasonable form.
The way things appear is not the way they are; and if things were as they appear, the whole of science would be unnecessary.
No one fights freedom; at most, they fight the freedom of others. Freedom has always existed, but at times as a privilege of some, and at other times as the right of all.
Political power is simply the organized power of one class to oppress another.
The engine of history is the class struggle.
Human beings make their own history, albeit under circumstances influenced by the past.
The dispossessed have a world to win.
Social progress can be measured by the social position of the female sex.