This paper examines the relationships between natural rights theory and contractualism, based on the difficulties raised by Locke’s thesis of the natural right to punish. To do this, it begins with Nozick’s political philosophy, which offers a very clear example of the anti-contractualist consequences of said thesis; it then continues with the philosophy of some theologians from Salamanca, who anticipated some of the problems that arise from a natural right of privates to punish. It will be held that the arguments of such theologians serve not only to dismiss such a right, but also to defend the necessity of the social contract in general.
