My primary aim is to reconstruct Marx's economic categories in terms of his social theory of alienation and vice versa. In other words, I reinterpret the social in the economic and the economic in the social by doing a close reading on Marx's early and later writings. My task is two-fold: first, to reveal within Marx's economic categoriesas they are expressed in Capital and his later writingshis social theory of alienation. And second, to extend his theory of alienationas it is forcefully expressed in his early writingsthrough talk of the inner-workings of capital, that is to say, by infusing the structure of alienation with the language of economics. I argue that Marx's social theory of alienation underlies his labor theory of value, along with all the corresponding economic categories that unfold from it. I reconstruct Marx's conception of human nature to show how it informs his theory of alienation, and how the latter ultimately anchors his socio-economic-historical analysis of capitalist society and his conception of freedom. I conclude by sketching Marx's vision of the new society, that is, his conception of a non-alienating mode of production based on my reinterpretation.