The fact that labour is external to the worker, i.e., it does not belong to his intrinsic nature; that in his work, therefore he does not affirm himself but denies himself, does not feel content but unhappy, does not develop freely his physical and mental energy but mortifies his body and his mind. The worker therefore only feels himself outside his work, and in his work feels outside himself.

It is not the consciousness of men that determines their being, but, on the contrary, their social being that determines their consciousness.

...the very cannibalism of the counterrevolution will convince the nations that there is only one way in which the murderous death agonies of the old society and the bloody birth throes of the new society can be shortened, simplified and concentrated, and that way is revolutionary terror.

Force is the midwife of every old society pregnant with a new one.

The last capitalist we hang shall be the one who sold us the rope.

The materialist doctrine that men are products of circumstances and upbringing, and that, therefore, changed men are products of other circumstances and changed upbrinding, forgets that it is men that change circumstances and that the educator himself needs educating.

The product of mental labor - science - always stands far below its value, because the labor-time necessary to reproduce it has no relation at all to the labor-time required for its original production.