 However, the concept of freedom as rational self-government did not disappear, John Locke, in his Two Treatises Concerning Government, accepted that we are politically free only when governed by a rational law. He argued that the reason why a man only attains to the status of a freeman at the age of maturity is that to be free is to be guided by reason (Locke 1689[1967]). Thus political freedom corresponds to being governed by a rational law, which is the law of nature. However, Locke undermined the epistemological basis of his political principles, which require that there is a moral “law of nature” discoverable by reason, when he insisted, as part of his empiricism, that there is no innate knowledge of principles. While Locke himself thought that reason could discover the rational validity of the law of nature, by reflecting on ideas that we have acquired through sensation and reflection, only a few subsequent writers were convinced by his reasoning. Some, such as Shaftesbury and Hutcheson reintroduced a form of innate knowledge, which nevertheless seemed respectably empirical, by developing the idea of a moral sense. Another anonymous “Remarker”, whose identity is unclear, argued that the closest that an empiricist such as Locke could get to a moral doctrine was a form of Epicureanism, which would reduce morality to enlightened self-interest (Burnet 1989; Walmsley 2016). Hume, following the logic of empiricism, would come to essentially the same conclusion, without seeing this as problematic. The Remarker’s critique of Locke was answered by Catharine Trotter Cockburn, whose attempt to defend Locke was praised by him, but not ultimately fully worked out. Nevertheless, the position that Cockburn developed in later works has some similarities with that which Macaulay defends (Cockburn 1702; Green 2014, 34–39, 172–79). According to Macaulay, there is an immutable moral truth that can be discovered by reason, and as Cockburn will come to do, she uses the concept of “fitness” to explain this process of discovery. Macaulay’s language is also very close to Samuel Clarke’s. But, while Cockburn was directly influenced by Clarke (Bolton 1996; Sheridan 2007), Macaulay claims that she did not read his works until after she had completed her Treatise (Macaulay 1783, viii). She proposes that there is a rule of eternal right grounded in,