That Aristotle has a place in the history of natural rights would not have seemed a startling proposition a hundred years ago. Ernest Barker declared in 1906 that for Aristotle, "the life-breath of the State . . . is a justice which assures to each his rights, enforces on all their duties, and so gives to each and all their own." This conception of justice stands in some contrast with Plato's, according to Barker. "While Plato's formula is that each individual should do his own, Aristotle's formula is that each individual should have his own. Plato thinks of the individual as bound to do the duty to which he is called as an organ of the State: Aristotle thinks of the individual as deserving the right which he ought to enjoy in a society based on (proportionate) equality."(1)
Not everyone agreed with Barker when he wrote those words. Few students of the Politics would agree with him today. Disagreement comes from different sides. On one hand--the "rights" hand, one might call it--Karl Popper argued in 1945 in The Open Society and its Enemies that Aristotle's essentialism was less interesting than Platonism but equally congenial to modern totalitarianism.(2) On the other hand--call it the "anti-rights" hand (although by no means the left or leftist hand)--scholars such as Alasdair MacIntyre and the legal historian Michel Villey would have it that the whole modern conception of rights, especially human or natural rights, is a pernicious fabrication of the Enlightenment, with roots going back no further than the similarly pernicious nominalism of William of Ockham.(3) As far as the current consensus is concerned, then, whether one favors rights or not, and whether one admires Aristotle or not, there are no rights--or at least no individual natural rights--in Aristotle.
Against this forbidding background Fred D. Miller, Jr. argues that for Aristotle "there is only one constitution which is everywhere according to nature the best" and that "that constitution is best according to nature which is unqualifiedly just and which guarantees the rights of its citizens according to this standard."(4) The paper is a necessarily sketchy attempt to determine, in effect, whether later thinkers read the Politics as Miller does or as Villey, MacIntyre, and others do.(5) I will focus mainly on the thirteenth and fourteenth centuries, the period in which Aristotle's political thought was taken more seriously than at any other time before or since and also the period in which something like a modern conception of natural rights becomes indisputably visible in contemporary theory.(6)
What is a modern conception of a natural rights? What sort of rights is the argument about? Within the Aristotelian tradition there is no doubt that some goods and some normative principles are natural or reasonable rather than conventional or arbitrary. At least that is the professed position, although Aristotle has been criticized by philosophers as different as Thomas Hobbes and Alan Gewirth for following the values of his own time or class rather than following nature or reason.(7) At least theoretically, however, there is no contradiction here between Aristotelians and modern defenders of natural rights.
Having mentioned Hobbes, let me concede at once that his concept of a natural right is in one respect quite different from anything in Aristotle. Fundamentally or naturally, for Hobbes, everyone has rights to everything. These rights are emphatically not compatible with one another as regards their full enjoyment. On the contrary, the war of all against all is a necessary consequence of this situation with regard to natural rights. It is therefore necessary for Hobbes that we give up our natural rights if we want peace and security. Aristotle is no Hobbes.(8) However, Hobbes is not the only modern theorist of natural rights. The possibility remains of a connection between Aristotle and modern theories in which the function of political justice is the guarantee or defense of natural rights, not their replacement. …