This chapter asks where Kant stands on one of the most famous contentions of ancient ethics: the so-called Unity of the Virtues, the claim that a person who has one of the virtues must have all of them. The twentieth-century revival of virtue ethics was partly prompted by explorations of this proposal – its centrality to ancient theories and its presumed implausibility for philosophers today. Kant announces that he rejects three ancient premises about virtue, the first of which is “there is only one virtue and one vice”. The chapter argues that he thereby rejects the Unity of the Virtues, as the Stoics conceive of it. For Kant, virtue-singular is prior to virtues-plural, but it is not one. The virtues-plural are not parts of virtue; the latter is not a whole in the way the Stoics take it to be. Nevertheless, Kant shares more with the ancients than with twentieth-century philosophers writing on the topic. He endorses the premise that virtue-singular is prior to the virtues-plural.

This chapter argues against a dominant reading of the Stoics according to which all appropriate actions (kathēkonta), whether drinking when thirsty or standing firm at a critical juncture in battle, count equally as “duties” (officia). All scholars interpret the Stoic Sage’s perfection to imply that absolutely every token action of the Sage counts as a (morally) perfect action (katorthōma), with the result that there is no category of actions constituted by the morally permissible. Appreciating the significance of the misunderstood Stoic category of “intermediate appropriate actions,” however, makes clear that there are actions that follow nature, but that are simply concerned with pursuing “promoted indifferents.” Thus, it is argued that the Stoic position recognizes a class of permissible actions – even for the Sage, whose perfection consists rather in never acting contrary to virtue. The Stoics are thus much closer to Kant and their Socratic heritage than has been previously recognized.

In this chapter, I attempt to trace the influence of the Stoic tradition on Marcus Aurelius by focusing on his approach to impressions, material flux, and fate. The primary suggestion is that the influence of earlier Stoicism is best interpreted within the framework of how Marcus develops a normative response to the external world. It is within this context of getting to grips with fluctuating, alienating, and disturbing appearances that we should seek to locate his reception of the Stoic theories of the cognitive impression, material flux, and the philosophical life, more broadly. Such an emphasis on inculcating a reliable response in the soul to the outside world also helps to explain a much-discussed feature of the Meditations, namely the unusual incorporation of Epicurean atomism within the work. I also push back on recent claims that there is evidence of a flirtation with Platonism evident in this text. Marcus was an innovative interpreter of his tradition with a particular focus on psychological stability, but, for all that, he was also a thoroughgoing Stoic.