This article aims to show that in the socialist tradition, alongside Marx, there is a position as materialist that it would be valuable to combine with his powerful critique of capitalism. This perspective is that of Proudhon. His work is interesting in that it enables us to see in the 'working' man something else than a stubborn animal, de-subjectivized by capitalism and existing only as a means of production. This is why, if indeed this is anthropology, it may be called positive anthropology. By continuously and almost exclusively favoring the notion of alienation, Marx runs the risk of allowing a purely negative anthropology to emerge in his work.