Much of the scholarship on Thomas Jefferson characterizes him as a consummate immoralist. Yet he had a keen interest in morality and most of his reading–when he was not immersed in politics–was for moral study. Jefferson once told his physician, Vine Utley, that he seldom went to sleep without first reading something morally inspiring. Some Jefferson scholars consider him at best a moral dilettante with incoherent views. Others see him as a Stoic, interested in virtue as measured by both intentions and outcomes, who in later life became an Epicurean, weighing pleasure versus ends. Drawing on a careful reading of his writings and an examination of his known readings on morality, this study argues that Jefferson developed early a consistent moral sense–Stoical in essence and focused on his own moral improvement–and maintained it throughout his life.