" This is what the bourgeois political economists have done: they have treated value as a fact of nature, not a social construction arising out of a particular mode of production. What Marx is interested in is a revolutionary transformation of society, and that means an overthrow of the capitalist value-form, the construction of an alternative value-structure, an alternative value-system that does not have the specific character of that achieved under capitalism. "

― David Harvey , A Companion to Marx's Capital