• tags :: capitalismsurplus-value

• source :: Capital Vol. 1Capital Vol. 2

Marx's theroy of surplus-value can be summarized as (from vol. 2):

Productive capital, in performing its functions, consumes its own component parts for the purpose of transforming them into a mass of products of a higher value. Since labour-power acts merely as one of its organs, the excess of the product’s value engendered by its surplus-labour over and above the value of productive capital’s constituent elements is also the fruit of capital. The surplus-labour of labour-power is the gratuitous labour performed for capital and thus forms surplus-value for the capitalist, a value which costs him no equivalent return. The product is therefore not only a commodity, but a commodity pregnant with surplus-value.

That is to say, that surplus-value comes from a laborer performing labor upon a commodity to increase its value. The result is surplus-value.