Jacob T. Levy [who is, by the way, a distinguished member of the McGill faculty] observes a propos my little riff on Rambo's knife that while die-hard Randians may cultivate the fantasy of the lone heroic producer, free market proponents and libertarians generally embrace warmly the role of the division of labor in modern economies [and others as well.] He is quite right, of course. Indeed, they insist upon it.
The point of my imaginary course syllabus tracing all the preconditions and filiations of Rambo's knife was to emphasize the extent to which we are all deeply embedded in and dependent upon the collective and anonymous products of prior labor and invention. It is simply out of the question to untangle these dependencies so as to establish which of them are the result of rational bargains freely entered into. Hence it is impossible to argue plausibly that present day individual holdings of private property are justified morally because they have arisen out of free and equal exchanges in the marketplace.
Every one of us comes into the world endowed with a material and cultural inheritance that we have not earned and can never justify. There are no "takers" and "makers" in our society. All of the takers are makers, and all of the makers are takers. And quite often those who start out with, or end up with, the most stuff have worked considerably less industriously than those who start out and end up with the least.
It is this fact that constitutes the real justification for Marx's Critique of the Gotha Program slogan: "From each according to his ability; to each according to his need."