Marx’s Capital does not present an analysis of different economic ‘models’ of ‘themes’ (first the ‘simple commodity production’, then the ‘capitalist commodity’, etc.). It has a unique object of study, the capitalist mode of production (i.e. the immanent regularities and tendencies of capitalist social relations), which Marx analyses, first of all, in relation with the concept of value: From the first text in the period under examination, the Grundrisse (1857-8), to Capital (1867), Marx insisted that value is an expression of relations exclusively characteristic of the capitalist mode of production (CMP).
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