Talk of ‘rights’ has a long history, and there is no reason to suppose that people are going to talk any less about ‘rights’ in the near future. In the past particular attention was given to what were called ‘natural rights’; these were rights that were supposedly derived from and guaranteed by ‘natural law’ or the Roman ius naturale which corresponds to that ‘which is always good and equitable’.1 In other words a distinction was drawn between man-made law (or convention) and ‘the notion of an eternal and immutable justice’2 or ‘a universal pattern of action applicable to all men everywhere’.3 Philosophers, as one might expect, disagreed to some extent about what precisely were the natural rights that man had in consequence of this natural law. Locke, for instance, asserted that man had a natural right to property, life and liberty. Not all agreed on the first of these, at least. And they did not always have the same account to give of the foundation of natural law. Aquinas saw natural law as essentially the expression of God’s will. Others saw no need for a religious foundation. But for a long time there was widespread agreement that there was such a thing as natural law and rights derived from it.