Marx sharply criticized the contemplative materialism of the Young Hegelians, viewing "the essence of man" in isolation and abstraction , instead arguing that the nature of man could only be understood in the context of his economic and social relations.  Marx argued that understanding the origins of religious belief were not enough in moving towards its elimination; instead declaring that it was the underlying social and economic structure which gave rise to religious belief and that it was a transformation of this which was a necessary precondition to the elimination of religion. 
The third law, "negation of the negation", originated with Hegel. Although Hegel coined the term "negation of the negation", it gained its fame from Marx's using it in Capital . There Marx wrote this: "The [death] knell of capitalist private property sounds. The expropriators [capitalists] are expropriated. The capitalist mode of appropriation, the result of the capitalist mode of production, produces capitalist private property. This is the first negation [antithesis] of individual private property. [The "first negation", or antithesis, negates the thesis, which in this instance is feudalism, the economic system that preceded capitalism.] ... But capitalist production begets, with the inexorability of a law of Nature, its own negation. It [final communism, the synthesis] is the negation of [the] negation."