The Stoics have sometimes been credited with concern for appropriately moral motivation, based on their distinction between those actions they classify as appropriate (kathēkonta) and those they characterize, in addition, as done on the basis of virtue (katorthōmata). This chapter argues that the Kantian and Stoic views closely resemble one another in this respect: just as Kant’s motive of duty requires a singular interest in the rightness of dutiful action, so the Stoics suppose that virtue and actions that originate in virtue are the only objects of fully rational desire. Both theories recognize, as well, that many of our cognitions are not transparent to ourselves, so that we are often unaware of our own motives. This recognition speaks to the depth and complexity of Stoic intellectualist psychology and underlies Kant’s claim that the effort to understand our own moral condition is a “wide” duty of virtue.

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.

Kant and the Stoics both rely on a momentous argument, set out in Plato’s dialogues, for the conclusion that nothing is unconditionally good but wisdom, yet they differ on how to interpret it. The Stoics identify this wisdom with the perfection of technical or productive knowledge of nature, and they regard it as the sole good. Kant identifies this wisdom with the perfection of practical knowledge of the good, and, analyzing this knowledge along the hylomorphic lines implicitly suggested in Plato’s argument, he locates wisdom’s unconditional goodness – its morality, or moral goodness – in its agreement not with the object it produces but with its form, morality’s principle. Two contrasting accounts of morality’s relation to perfection thus emerge. The Stoics see perfection in the knowledge of nature as entailing moral goodness, whereas Kant argues that moral goodness is the condition of all other goodness, including that of perfection.