 It is a difficult question what precisely would count as the discovery of the will. Clearly, voluntas and velle (‘willing’, ‘wanting’) figure prominently in many of Seneca’s arguments. Does Seneca think there is a separate faculty of the will, thus modifying psychological monism? Or is he interested in exploring the phenomenology of decision-making and self-improvement, and this leads him to describe certain mental acts as acts of willing (velle)? This second suggestion seems more persuasive, and seems to capture much of what is important to the traditional interpretation: that Seneca keeps discussing how we must be continually committed to self-improvement (cf. Letters 34.3 and 71.36). Perhaps Seneca’s depictions of the mental act that the Greek Stoics call assent appear in some sense richer than those of the earlier Stoics (without changing the substance of the theory), because Seneca likes to use metaphorical language. Rather than stick with the abstract description that, in deciding what to do, we assent to a practical impression, Seneca envisages us as judges, passing judgment over what we should be doing, and issuing commands to ourselves (cf. Inwood 2005, [5] and [7]; Star 2012, 23–52). With respect to the emotions, Seneca distinguishes between involuntary reactions (what earlier Stoics call “proto-emotions” or propatheiai) and full-blown emotions, which involve assent and thus are voluntary (On Anger II; see below). They are voluntary in the sense that assent is in the agent’s power. This is a key piece of Stoic doctrine—that, whether we are foolish or wise, it is in our power to assent or not assent to impressions. But at other times, Seneca employs a normative notion of voluntariness. Only virtuous action is free in the sense of being fully reasonable, while other actions spring from irrational movements of the mind such as emotions; in this sense, only virtuous action is voluntary (Letter 66.16).