Do not let us go back to a fictitious primordial condition as the political economist does, when he tries to explain. Such a primordial condition explains nothing; it merely pushes the question away into a grey nebulous distance. The economist assumes in the form of a fact, of an event, what he is supposed to deduce- namely, the necessary labour and exchange. Thus the theologian explains the origin of evil by the fall of man; that is he assumes as a fact, in historical form, what has to be explained.
— Karl Marx - Estranged Labour - Economic and Philosophic Manuscripts of 1844 - Marx and Engels:1843-44 Volume 3 Collected Works
The bourgeois have very good grounds for fancifully ascribing supernatural creative power to labour, since it follows precisely from the fact that labour depends on nature, that the man who possesses no other property than his labour power must, in all conditions of society and culture, be the slave of other men who have made themselves the owners of the material conditions of labour. He can only work with their permission, and hence only live with their permission.
— Karl Marx - Critique of the Gotha Programme