In the Phaedrus we find a more detailed account of the psychology and art of love than in the Symposium. This account will be our exclusive focus. The soul, whether divine or human, Socrates claims, is like “the natural union of a team of winged horses and their charioteer” (246a6–7). But whereas in a divine soul all three elements are “good and come from good stock,” in a human soul the white horse (familiar from Republic IV as the honor-loving spirited element) is “beautiful and good, and of similar stock,” while the black one (the Republic‘s appetitive element) is “the opposite and of the opposite stock,” so that “the driving in our case is necessarily difficult and troublesome” (a7-b4). When spirit together with the charioteer (the Republic‘s rational element, there too identified with what is truly human rather than bestial in us (588b10–589a4)) “leads us towards what is best and is in control,” we possess moderation (sôphrosunê) (237e2–3). But when “appetite drags us irrationally towards pleasures and rules in us, its rule is called excess (hubris)” (238a1–2). Of this excess, gluttony is one species, but erotic love another (238b7-c4). This is the bad kind of love—Pandemotic in the Symposium—that Lysias rightly disparages in the speech Phaedrus admires and reads to Socrates (230e6–234c5).
In Socrates’ view, however, there is also another kind of love, namely, “the madness of a man who, on seeing beauty here on earth, and being reminded of true beauty, becomes winged, and fluttering with eagerness to fly upwards, but unable to leave the ground, looks upwards like a bird, and takes no heed of things below—and that is what causes him to be regarded as mad” (249d5-e1). This madman is the philosopher of the Symposium, who when he falls in love with a boy is led by his love to ascend by stages to the form of the beautiful. What makes his madness a divine gift, however, is that the ascent is now revealed as involving recollection of a prior pre-natal ascent taken in the company of a god.
From the rich literary account of this ascent, we need to take away just one idea: souls have different psychological structures depending on which god they followed, since this sets an upper limit on how much of the forms they see, and so how much they can subsequently recollect. Since gaining access to forms nourishes and strengthens the rational element in the soul (248b5-c2), this also helps determine their motivational structure: the stronger their reason is, the more likely it will be to succeed in controlling the other elements in the soul.
Followers of Zeus, for example, choose someone to love whose soul resembles their patron god. So they seek someone who is “naturally disposed to philosophy and leadership, and when they have found him and fall in love they do everything to make him philosophical” (252e1–5). Nonetheless, the falling itself involves a huge psychological upheaval. The black horse of appetite immediately urges towards sexual intercourse. The white horse—“constrained then as always by shame” (254a2)—holds itself back. Eventually, however, the black horse forces both the charioteer and the white horse “to move towards the beloved and mention to him the delights of sex” (a5–7). Again they balk, “indignant at being forced to do terrible and improper things” (b1). But finally, “when there is no limit to their plight, they follow its lead, giving in and agreeing to do what it tells them” (b2–3). As they come close to the beloved, however, to initiate intercourse, the flashing face of the beloved reminds the charioteer of the beautiful itself, so that his memory “again sees it standing together with temperance on a holy pedestal” (b5–7). He becomes frightened and “in sudden reverence falls on his back, and is forced at the same time to pull back the reins so violently as to bring the horses down on their haunches, the one willingly, because of it lack of resistance to him, but the unruly horse much against its will” (b7-c3). Eventually, “when the same thing happens to the evil horse many times, it allows the charioteer with his foresight to lead” (e5–7). If this control of appetite by reason and spirit continues—even when the boy has accepted his lover and embraces, kisses, and lies down with him—and draws them to “a well-ordered life and to philosophy,” they are blessedly happy here on earth, and, if they live such a life for three successive incarnations, they re-grow their wings and re-join the entourage of their god (255e2-b7).
When followers of Ares fall in love, on the other hand, they “adopt a lower way of living, not philosophical, but honor-loving” (256b7-c1). When they are drinking together, for example, or are careless in some other way, “the licentious horses in the two of them catch their souls off guard,” and since the man’s recollection of beauty is dimmer and is not rekindled by philosophical conversation, they end up having sex together—something “the masses regard as the happiest choice of all” (c1–5). Nonetheless, they don’t have sex very often, because “what they are doing has not been approved by their whole mind” (c6–7). So while the degree of their love and happiness is less than the philosophical pair and, on their death, “they leave the body without wings,” still they have an impulse, coming from love, to try to gain them. Hence they aren’t punished in the next life, but helped on the way to future happiness together (c7-e2).
The love that is divine madness is a good thing, therefore, especially when, “accompanied by philosophical discussions (erôta meta philosophôn logôn)” (257b6), it leads to the beautiful itself and the other forms, which are what we—as most of all the rational element in our souls—truly love and crave. The question is what makes a discussion philosophical? What makes it of the sort to be included in the true art of love that the philosopher who loves the beautiful itself practices? The answer now proposed is that it must be a technê or craft, and so must have the defining characteristics of one. As applied to love itself, for example, it must begin with a definition of love, and reach its conclusions by ordering its discussion in relation to it (263d5-e3). And this definition, in turn, must be established by what Socrates refers to as collection and division (266b3–4).
Collection is a process of “perceiving together and bringing into one form items that are scattered in many places” (265d3–4). It is a process that we, unlike other animals, are able to engage in it, because our souls include a rational element that has prior acquaintance with forms: “a soul that never [prenatally] saw what is true cannot take a human shape, since a human being must understand what is said by relation to a form that is reached from many sense-perceptions being collected into one by reasoning” (249b5-c1). (It is useful to compare this description with the one given in Aristotle, Posterior Analytics II. 19.)
Once a form has been reached in this way, division begins. This is a matter of “cutting the form up again, by relation to [sub-]forms, by relation to its natural joints” (265e1-2). As an example, Socrates cites the case of love itself:
just as a single body naturally has its parts in pairs, with both members of each pair having the same name, and labeled respectively left and right, so the two speeches regarded madness as naturally a single form in us. The one [Socrates’ reorganized version of Lysias’ attack on love] cut off the part on the left side, then cutting it again, and not giving up until it had found among the parts a love which is, as we say, “left-handed,” and abused it with full justice, while the other speech [Socrates’ own defense of love] led us to the parts of madness on the right-hand side, and discovering and exhibiting a love which shares the same name as the other, but is divine, it praised it as a cause of our greatest goods. (265e4–266b1)
Thus, while each speech tells only half the story, the two together show how correct division should proceed. The goal, however, isn’t just truth or correctness, but explanatory adequacy. Thus if the form in question “is simple, we should consider…what natural capacity it has for acting and on what, or for being acted upon and by what,” and if it is complex, we should count its sub-forms, and consider the same things about them as about the simple ones (270d3–7). That Socrates—the archetypal searcher for explanatory definitions (Euthyphro 6d9-e6)—should pronounce himself “a lover of these divisions and collections” is no surprise, therefore (266b3–4).
Philosophy aims at true definitions and true stories based on them. But it also aims at persuasion, since the philosophical lover wants to persuade his boy to follow him on the path to the forms. Philosophy and rhetoric must thus go together, which means that rhetoric, too, must be developed as a technê. It must, first, distinguish and give definitions of the various kinds of souls and kinds of speeches, revealing their respective capacities and susceptibilities, and, second, “coordinate each kind of soul with the kind of speech appropriate to it, explaining why one kind of soul is necessarily convinced by one kind of speech, while another is not” (271b1–5). Mastery of such a science, however, requires one further thing: “the student must observe these things as they are in real life, and actually being put into practice, and be able to follow them with keen perception” (d8-e1). It isn’t enough, in other words, to know what kinds of speeches affect what kinds of soul, the philosophical rhetorician must also know that this man in front of him is of such and such a kind, and be able to talk in the kind of way that will prove convincing to him (e2–272b2).