 It has often been noted that later Stoics, including Seneca, seem to lose interest in the ideal agent—the sage or wise person—who figures so prominently in early Stoic ethics. Rather than assume that the later Stoics are disillusioned or more realistic, we should note that Seneca’s focus on the progressor (proficiens)—the person who is seriously trying their best to move forward in their way of life toward that ideal—is part and parcel of his own, specific way of doing philosophy. The early Stoics’ sage may, first and foremost, be a tool for developing theories. The early Stoics spell out what knowledge or wisdom is by explaining what a knowledgeable or wise person would do (how she assents, how she acts, etc.). But Seneca’s philosophy is a practice of training ourselves to appreciate to the fullest the truths of Stoicism. In this practice, accounts of, for example, the wise person’s assent, can only play a limited role. We need precisely what Seneca offers: someone who takes us through the various situations in life in which we tend to lose sight of our own insights, and fall victim to the allurements of money and fame, or to the violence of emotions evoked by the adversities of life. We need to learn how to overcome our own residual tendencies, despite our better intentions, to suffer such failures.