Abstract
<p>The question why Locke failed to publish an ethical system, notwithstanding the value he placed on the moral life, is raised and its answer postponed. Locke’s thoughts about ethics expressed in the <italic>Essay</italic> and other writings are examined, their sources identified, and the systematic connections between them are considered. Hellenistic sources, especially Epicurean ones, are identified, along with the ethical rationalism and naturalism of Hugo Grotius. Following Grotius, Locke developed a theory of the law of nature, rooted in social convenience, but sanctioned by divine command. In <italic>Some Thoughts concerning Education</italic>, Locke advocated the cultivation of virtues suitable to the moral and civic life of a gentleman. His abortive attempt to develop a system of ethics in ‘Of Ethics in General’, intended as a chapter of the <italic>Essay</italic>, but abandoned, brings the reader back to the opening question. Locke concluded that revelation is a more reliable source of moral knowledge.</p>