2.1 The Idea of the Good as the First Principle of All

In Republic Book 6, Socrates says:

There are many issues raised by this passage including how the Idea of the Good is to be studied and how it actually makes justice and other things useful or beneficial.Footnote ² It does seem beyond doubt, however, that what is here being claimed is, minimally, that the Idea of the Good has a fundamental role to play in Plato’s moral realism. I put this claim in this anodyne manner not because I do not think that a much stronger claim can be substantiated; I do so because even such a claim has been widely rejected, especially but not only in the English-speaking world for well over a century.Footnote ³ It is held that the Good is redundant because justice and other virtues are good by definition. That is, the Good does not add anything to knowledge of the Forms of the Virtues. This possibility seems challenged by the fact that the study of the superordinate Good is “the most important study.” Indeed, as we learn a bit later in the passage on the Divided Line, the study of the Good is the greatest study at least because without knowing it, we cannot even know the definitions of the Virtues, let alone know that it is good or beneficial for us to possess instances of them.Footnote ⁴

Recognizing that the Idea of the Good makes justice useful or beneficial, one may object that then it cannot be the case that justice is intrinsically good; rather, goodness will be external to justice in some way.Footnote ⁵ Such an objection arises from a limited conception of how Plato conceives of the relation between the Good and the Forms. The Good is the explanation for the existence and essence of all the Forms.Footnote ⁶ Goodness is as intimately present to the Form of Justice as is its own οὐσία, if for no other reason than that whatever causal role the Good has in relation to Forms, it has eternally. The Good is also intimately, albeit indirectly, related to any instantiation of the Good via an instantiation of Justice and the other Forms. As a synonym for “instantiation” we might use “manifestation” or even “expression,” bearing in mind that instantiation is not instrumentality but, for Plato, participation.Footnote ⁷ In the eternal or intelligible realm, all relations are internal including the relation between that which participates and that which is participated in. So, Justice is intrinsically beneficial, not because of what the word “justice” means, but because of its eternal participation in the Good. And since this eternal participation is an internal relation, goodness is constitutive of the identity of Justice and the other Forms, too.

If the Idea of the Good is not relevant to the acquisition of virtue or anything else that is beneficial, or to the knowledge of it, then the following problem arises. It is a problem to which I have already alluded. Our paradigmatic malefactor, the tyrant, can without reservation concede that virtue is a good. He can also concede the supposedly “Socratic” point that what may seem to be a good is not really so if one does not know how to use it.Footnote ⁸ So much hardly steps outside the bounds of ordinary ancient Greek language and common sense. A virtue is good just because it is one of the things that people aim for, alongside health, wealth, beauty, pleasure, power, friendship, security, and so on.Footnote ⁹ They may well dispute what the virtue consists in or what its definition is, but the fact that someone pursues it means at a minimum that it is an apparent good, that is, a goal the achievement of which appears to the agent to be one that he or she truly desires. Even if the tyrant refuses to accept that some states or practices are virtues, for example, piety or justice, he can hardly wish to deny that there are some virtues including say, courage and endurance. And these will be at least prima facie goods. But at the same time, it is always open to the tyrant to say that, though some virtues are indeed goods, it is not good for him to have them or to practice them at this time and under these circumstances.Footnote ¹⁰ Another way of putting this point is that what may appear to be goods to some people are not good for him. Or at least, they are defeasible goods when measured against others.

Given the subjectivity and the ordinality of the valuations that people – ordinary people as well as tyrants – make, it is entirely possible to recognize virtue as one good among many. Sometimes, the self-interested calculations of people lead to the practical conclusion that in certain circumstances a good other than virtue needs to be prioritized. After all, it is not unreasonable to hold that A is the most important thing ceteris paribus, but that B has some importance too, and that from time to time, one should act to attain B rather than A. To be instructed by a “Socratic” critic that there are more important things in life than B is to invite the reply, “not here and now there aren’t.” Something like this must have been going through the mind of Crito in his eponymous dialogue when, at a critical moment, he hears Socrates’ decision to privilege the good of virtue over the good of human life. Socrates’ decision in this regard does not automatically invalidate or reduce to absurdity a contrary decision by someone else.

Just a few lines after the passage quoted at the beginning of this chapter, Socrates provides what I take to be the conclusive reason for the centrality of a superordinate Idea of the Good in Plato’s ethics. This is the passage indicating the Good as that which all desire and the fact that everyone divines that it is something, although they do not know what it is.Footnote ¹¹

Suppose that it is not the Idea of the Good that makes justice really good for oneself as opposed to merely being apparently good. If that which does this is not above οὐσία, then it is or has an οὐσία of its own. For example, say that what makes justice good for oneself is that the Form of Justice partakes of another Form, the Form of ἀταραξία (absence of anxiety). It is then open to the tyrant to ask why absence of anxiety should be the stopping-point. That is, why should it be assumed that absence of anxiety is really good for oneself? Or always good for oneself? It seems that for the possession of an instance of any οὐσία, the question of the real good for oneself continues to remain open. Hence, in order to avoid begging the question, the “good at which all things aim” must be beyond οὐσία.Footnote ¹²

Terry Penner has argued that the Idea of the Good is just the Form of Advantage.Footnote ¹³ This seems to be taken by him to be synonymous with a putative Form of Happiness. So, in answer to the question of why one should be just, Socrates (or Plato) would say, “because you want what is really good for yourself and what is really good for yourself is advantage, which is equivalent to happiness.” Set aside for the moment the implausibility of this interpretation based solely on the fact that the Idea of the Good is what makes all Forms knowable and provides truth to them, not only the so-called ethical or normative Forms.Footnote ¹⁴ How a Form of Advantage makes, say, Circularity knowable is, to say the least, mysterious. Penner is correct, of course, in supposing that Plato believes that all human beings desire to be happy and that for them, the real good is happiness.Footnote ¹⁵ Socrates insists that happiness is found in virtuous living. The tyrant protests that this might be so for the many but not so for the few. For those who are up to the challenge, the life of the tyrant is to be preferred. It is in that life that happiness is to be found. Penner’s Socrates is in no position to reply that it is impossible for a tyrant to be happy. This is so because either happiness is a purely formal term or else it has content, presumably, the content of Virtue. If it is a formal term, then a “prudential” Socrates has no grounds for excluding the exceptions to his rule that the tyrant claims. If the Form of Advantage has content, namely, Virtue, the tyrant, it seems, can still legitimately ask why being virtuous is more than merely apparently good.Footnote ¹⁶ Or he can ask why the demands of virtue are not defeasible.

The Idea of the Good has to be above οὐσία in order to attain to the universality of an ethical theory, at least for any theory that is even remotely plausibly Platonic.Footnote ¹⁷ Stated otherwise, the unhypothetical first principle of all has to be the Idea of the Good if Plato is to have an ethical theory of any kind. Eliminating the Idea of the Good or discounting its ontological significance is tantamount to saddling Plato with the inability to advance beyond rhetoric in Socrates’ exhortations to his interlocutors to live a certain kind of life. It is a mistake to conflate the universality of the Idea of the Good with the universality of any Form. For it is the uniqueness of a superordinate Idea of the Good that alone provides the requisite universality for moral realism.Footnote ¹⁸ This universality must be “unhypothetical” because it is a stopping-point or first principle. Only that is something sufficient (τι ἱκανόν) as an explanation, in the present case for the truth of moral claims. The explanatory stopping-point is then identical with the goal or τέλος of all action.

2.2 The Idea of the Good and the Form of the Good

There are a number of passages in the dialogues in which Plato speaks about a Form of the Good which appears to be coordinate with other Forms as opposed to being “above” all Forms.Footnote ¹⁹ By “coordinate” I mean one οὐσία among many.Footnote ²⁰ So, the obvious question arises as to why a coordinate Form of the Good is not sufficient to do the job that Plato needs the Idea of the Good to do. I have already suggested the answer to this question along the lines of the absolute priority of the first principle of all. But a stronger reply can be formulated if we include the reason why a superordinate Idea of the Good does not preempt a coordinate Form of the Good such that the latter becomes otiose.

Proclus in his remarkable book of essays on Republic sees clearly the need to distinguish a coordinate Form of the Good from a superordinate Idea of the Good.Footnote ²¹ Proclus identifies the former as the genus of perfections (τελεώσεις) and the latter with the unhypothetical first principle of all.Footnote ²² The genus of perfections is distinct from the genus of substances (οὐσίαι). Among these are Human Being and Horse. Among the “species” of the genus of perfections are Beauty, Justice, Health, Strength, and so on.Footnote ²³ What the latter all share is there are various ways in which a human being can be perfected or completed. That is, there are various ways in which we strive to bridge the gap between our human endowment and the achievements that comprise our fulfillment as human beings.Footnote ²⁴ Proclus thinks it obvious that perfections as different as beauty and virtue have, nevertheless, a generic unity. This is analogous to the specific unity that, say, physical beauty and intellectual beauty have in Symposium. But there is an important reason why this coordinate Form of Good, the genus of perfections, cannot substitute for the superordinate Idea of the Good.

The coordinate generic Form of the Good is an οὐσία in which all its species participate. Things or states that are bad or neutral do not participate in it. Thus, the Form of the Good lacks the universality of the superordinate Idea of the Good. Its nature is absent from things that do not participate in it. This is owing entirely to its being a limited nature in which participation or lack of participation is possible.Footnote ²⁵ By contrast, the superordinate Idea of the Good is not limited in any way. Everything with an οὐσία of any sort participates in it including things with radically disparate natures. It is true that Plato does not make explicit the distinction between the Form of the Good and the Idea of the Good, but since he does explicitly make the latter “beyond οὐσία,” it is not, I think, unreasonable to suppose that he means to distinguish it from anything that has an οὐσία including the coordinate Form of the Good.

The coordinate Form of the Good is the eternal foundation for facts of a particular sort.Footnote ²⁶ Whether someone is or is not virtuous or healthy is an objective fact, quite independent of his or her own perceptions or beliefs. This is true generally for all the coordinate Forms which provide the explanation for the real or objective samenesses and differences in the sensible world. But the validation of a claim to objective fact, for example, that Socrates is virtuous and Callicles is not, does not and cannot answer any questions about normativity. When Plato lays down the principle that everyone desires the real good, he is not making the banal claim that everyone seeks to perfect themselves according to their own ideas of what perfection consists of. The presence of a real good as opposed to a merely apparent good is determined according to a norm, not a fact. The norm is set by nature as an achievement as opposed to an endowment. It must be a real, not a merely notional norm. Without an ontological foundation for the norm, though objectivity may still be supported, universality is not. An anti-Platonic scientific approach to ethics can be content to endorse a pallid form of normativity based, for example, on evolutionary biology or sociobiology. Or no normativity at all. Without the superordinate Idea of the Good, this is the right approach to take. On this approach, there is no room for Socrates’ absolutism. In this regard, Penner’s prudentialism is actually closer to an anti-Platonic position than to Plato’s own as expressed in the dialogues.

A multiplicity of universal norms runs up against the problem canvassed above, namely, that they will each have to have content, thereby leaving necessarily open the motivational question.Footnote ²⁷ Mere objectivity is strictly compatible with relativism whether at the individual or group level. Only universality can yield exceptionlessness, like the exceptionlessness of mathematics; but only the unique universality of the superordinate Idea of the Good can yield normative exceptionlessness. There is no way to achieve normative universality or absoluteness without a unique normative principle that transcends “content.” In a hierarchical metaphysics, this principle is bound to be the first principle of being. No matter how bizarre or even repugnant one may find this view, it seems to be the view that Plato holds.Footnote ²⁸

There is a fairly obvious objection to this view, an objection found as frequently among those sympathetic to Plato’s ethics as among those who are not.Footnote ²⁹ The objection is that the universality here outlined is entirely inappropriate as a foundation for the rich, contextual human world.Footnote ³⁰ An exhortation to strive for and embrace the superordinate Idea of the Good should only be met with derision by anyone struggling to do good and avoid evil in real life. Plato’s response to this objection is twofold. First, the Good is instantiated here below via the Forms. And the Forms are the paradigms of all possible intelligible content. That is, any ethical theory will ultimately need to appeal to the definitional content of Forms in order to make intelligible its normative claims. Second, the precise way in which, say, the Form of Justice is to be instantiated is not, alas, immediately entailed by a recognition of a superordinate Idea of the Good that makes just acts useful or beneficial.Footnote ³¹ One naturally struggles to find some heuristic to apply the results of having engaged in “the most important study.” There seem to be at least three.

First, if Good is universal, then it is not possible that something, say, some action, should be good for A and at the same time not good for B. The obvious parallels are found in the truths of mathematics. Another way to put this is to say that if the Good is instantiated here and now, it is otiose to add “for me” to the proposition that represents the good state of affairs. Thus, if benevolent kingship is good for Athens, then it is true, but also needs no saying, that it is good for me, an Athenian citizen, that a benevolent king rules. More interesting and related to the role of the Good in illuminating the Socratic paradoxes, if it is good that I be punished for my wrongdoing, then it is good for me that I be punished for my wrongdoing. Conversely, if it is good for me that I obtain something or do something, then we can infer that it is good simpliciter that this occur.

How does this logical point about the universality of Good yield a heuristic? If I am right in believing that, say, just deeds are good owing to the Idea of the Good, then I can infer that they are good for me. Similarly, I can infer that it is bad for me to do an unjust deed.Footnote ³² Then, my doing an unjust deed can never be in my interest. Plato surely believes this on any account of his ethics. But on the prudentialist account, it does not follow that doing just deeds is in everyone’s interest even if Justice, like all the Virtues, is a species of perfection. Thus, I can never achieve my good by being unjust to anyone else. Clearly, knowledge of what justice is is crucial to the task of being just and of benefiting oneself. But this knowledge is only dispositive in determining action on behalf of my good if the Form of Justice participates in the superordinate Idea of the Good which is the object of my will. Suppose that knowledge of what Justice is includes, minimally, knowledge that intentionally harming an innocent person cannot constitute a just deed. If that is so, the heuristic indicates that one refrain from aggressing against anyone. Needless to say, agreeing to this would amount to a huge concession on the part of the tyrant. His devotion to the idea of life as a zero-sum game leads him to think that his own good can often only be advanced at the expense of others.

Let us dig a bit deeper for a more problematic case. Someone employing a utilitarian calculus might argue either that (a) if the greatest happiness of the greatest number is attained, then injustice done to the few is good or that (b) if the greatest happiness of the greatest number is achieved, then no injustice is thereby done whatever is in fact done to a few. It seems that on the basis of the universality of the Good, Plato would decisively reject both alternatives. The first is rejected in Socrates’ absolutist prohibition of injustice in Crito.Footnote ³³ The rejection of the second alternative follows from Socrates’ refutation of Thrasymachus’ definition of justice as the advantage (συμφέρον) of the stronger.Footnote ³⁴ This claim is rejected for all cases of “the stronger” including the majority in a democracy. Attaining advantage for the majority presumably entails disadvantage for the minority, that is, the weaker; otherwise, it would be for the advantage of all. According to Thrasymachus, the advantage of the majority (if it is stronger) is just for all.Footnote ³⁵ The rejection of this position by Socrates entails the rejection of (b). If this is so, here is a strong, albeit negative, heuristic based on the universality of the Good.

This heuristic is also sharply circumscribed since the possibility of doing something apparently good that has adverse consequences for someone sometime is considerable. And the “greater” the good that one aims to do, the greater the chance of bringing about these consequences. In the face of this, one might attempt various strategies. For example, one might introduce degrees of goodness. So, one doesn’t calculate whether doing something to A has or has not a bad effect on B, but whether bringing about A-B is, on balance, a greater good than not doing so. In other words, one tries to contextualize the effects of acting and then shape the demands of virtuous behavior accordingly. Alternatively, one might introduce a doctrine of unintended consequences or of “double effect.” According to such a doctrine, if doing something good to A has the unintended effect of producing something bad for B, then this does not “count” as a failure of virtue. Admittedly, both of these strategies are fraught with possibilities for abuse. It should also be noted, however, that truly unintended side effects of one’s behavior – if they are unforeseeable – cannot, ex hypothesi, be part of a calculation regarding doing good and avoiding evil. But often, and especially at the political rather than personal level, unintended side effects are reasonably foreseeable. At this level, it is difficult to see how an absolutist prohibition of wrongdoing would not be violated. The cascading consequences of behavior and the circumscription of the first heuristic suggest a certain skepticism about instantiating the Good or at least of trying to do so via laws or rubrics. Understandably, Plato hoped that a philosopher with knowledge of the Good would be best placed to make circumstantial judgments about how the Good should be brought about case by case.

The second heuristic for the instantiation of the Good follows from the necessary absolute or unqualified simplicity of the unhypothetical first principle of all and from its being identified with the Idea of the Good. As Plato says in Republic, “the virtuous person becomes one out of many (ἕνα γενόμενον ἐκ πολλῶν).”Footnote ³⁶ I shall have much more to say about the Good as One later in this chapter, but for now it should suffice to indicate that unification according to kind or integrative unity is a standalone criterion of goodness for Plato even though its effective implementation depends on having at hand definitions of the natures whose unity is sought, including species of living things and forms of association like a state or a family.Footnote ³⁷ The optimal state for any natural or even for any artificial construct is integrative unity.Footnote ³⁸ In nature, integrative unity maps the steps from endowment to achievement, from the kind of thing one is by nature to the fulfillment of that nature.Footnote ³⁹ The diversity of types of integrative unity once again indicates the necessity for the first principle of all to be beyond οὐσία. The Good or One is a principle of integrative unity, and in its absolute simplicity, it is beyond any need for an integration of parts. But for this to be more than merely notional, the Good or One must be, as Plato says explicitly, the source of the being of everything that has the complexity of an existent with an essence. In eternity, endowment and achievement of integrative unity coincide; in the temporal world, where being is “spread out” across time (and space), integration is not inevitable. But it is the only way that the Good is achievable.

The third heuristic is offered in Philebus where we learn that the Good cannot be grasped on its own.

I shall have more to say about this triad of criteria in Chapter 6. Here I only want to emphasize that this triad is potentially the most powerful heuristic of all in determining whether or not the Good is being instantiated. It indicates implicitly integrative unity (“treat these as in a way one”), but it also indicates the relational properties of truth, beauty, and symmetry: Truth is the property of being in relation to our intellects, beauty is the property of being in relation to our desire or appetite, and symmetry is the property of being in relation to authentic imaging of it in the sensible world.Footnote ⁴¹ Thus, in reflecting on the truth, the beauty that attracts us, and the symmetry of the parts of real images of Forms, we have something of a guide to action.

The Idea of the Good provides truth to the intelligible world, thereby making its inhabitants knowable.Footnote ⁴² It is itself “more beautiful (κάλλιον)” than this world, drawing things to itself by drawing them to the intelligible world.Footnote ⁴³ In short, the Good is the principle of beauty and truth. It is puzzling how symmetry (συμμετρία) fits into this picture until we see the Good as the One. For symmetry is virtually identical with integrative unity. All genuine symmetries are “true” images of the first principle, the paradigm of all being.Footnote ⁴⁴ The Good or One is virtually all the intelligible world.

These three heuristics, even when used together, fall short of a comprehensive formula for determining how to live a good life or how to act so that the Good is instantiated in it. Political τέχνη is indispensable in this regard. Nevertheless, these heuristics in fact exclude a great deal from consideration – such as utilitarianism and relativism – and are action-guiding in countless ways. Most important, these criteria make no sense without the superordinate Idea of the Good. They make no sense if achieving one’s own good cannot be grounded in supersensible metaphysics, in particular in a principle that is both without specific essentialistic content and at the same time, explanatory for all the intelligible content that there is.

I shall conclude this section with one additional consideration in favor of the necessity for distinguishing a coordinate Form of the Good and the superordinate Idea of the Good. The latter, as we have seen, makes Justice and other Forms “useful or beneficial.” The superordinate Good is not required to make any “perfection” a good. Unless we distinguish the Idea of the Good “from everything else,” we are powerless to answer the question of whether the possession of one or more of these perfections is actually useful or beneficial.Footnote ⁴⁵ Wisdom or knowledge does not determine whether, for example, pleasure or health is a good, but only whether it will be circumstantially useful or beneficial to us to have that good. Conflating the coordinate Form of the Good and the superordinate Idea of the Good forces one to say that physical health is not something that human beings desire, ceteris paribus, since it is undoubtedly true that a fully healthy vicious person can do more harm to himself and to others than if he were prostrate with illness.Footnote ⁴⁶ Conflating the coordinate Form of the Good with the superordinate Idea of the Good would also threaten the argument in Book 4 of Republic that justice is desirable in itself (i.e., good) just as is physical health. By contrast, distinguishing the Form and the Idea allows us to recognize and endorse the obvious fact that people want pleasure and health and so on without conceding that the unalloyed Good that they seek is identical with either of these. And indeed, achieving this Good might even require us to forgo one or more of these goods.

2.3 The Idea of the Good as Beginning and as End

The Idea of the Good is “in a certain sense the cause of all things (τρόπον τινὰ πάντων αἴτιος).”Footnote ⁴⁷ Its causality is represented by the metaphor of “overflowing (ἐπίρυττον),” an activity that is unlimited in any way since the Good is beyond οὐσία.Footnote ⁴⁸ It is also, as we saw in Section 2.1, that at which everything aims. The simple conjunction of these two claims yields a particularly powerful conclusion. Apparently, it was a conclusion that Speusippus, Plato’s successor, could not accept. For according to Aristotle, he maintained that the good for human beings must be separate from the first principle of all, the One.Footnote ⁴⁹ Presumably, Aristotle mentions this because he thought that Speusippus held this position in opposition to Plato. If this is so, this supports the claim that Plato identified the Good as source with the Good as goal.Footnote ⁵⁰ Why is the cyclicity of the identification of the beginning and the end so importantly different from the centrifugality of the Speusippian position? With the view of Speusippus or anything like it, the source of all being is no guide to the attainment of the good for human beings or for anything else. On this view, the only possible guide to that which is really good is how that appears to each one. By contrast, for Plato the source of being is the only guide to the attainment of the Good, whether through one or more of the three heuristics discussed in the previous section or in some other way. No doubt, this is why the Good is the object of “the most important study.” The situation of ethics within a metaphysical framework and therefore the rejection of its autonomy sets Plato’s ethical theory apart from most others.

Later Platonists made much of the coincidence of the first principle of all and the real Good that we all seek. Plotinus famously insisted that in order to know who we are we have to know where we come from.Footnote ⁵¹ And, naturally, we have to know who we are in order to know how to achieve our own good.Footnote ⁵² Nevertheless, in order to escape the suspicion that Plato has simply stipulated that the beginning is the end by giving them the identical name, it is necessary to ask for some rationale within a Platonic framework for this far-reaching claim. Here are the assumptions I find operating beneath the seemingly cavalier conflation of the answers to two questions: What is the first principle of all and what is the good life for a human being?

First, as I have already suggested, Plato is very much in line with all ancient Greek thinkers in taking nature (φύσις) to have a dual aspect. That is, there is a distinction between nature as an endowment and nature as an achievement. Normativity is found in the interstice between the two and depends on a first principle of normativity that explicitly transcends appearances.Footnote ⁵³ What is good for someone, or some thing, is to become what it is in the fullest possible way. With this assumption, Plato takes his own path in arguing that the paradigms of the natures of things are eternal Forms.Footnote ⁵⁴ But since there must be a first principle of all, which is the cause or explanation for the combination of existence and essence that constitutes any Form, this principle is in a way the paradigm of the natures here below.Footnote ⁵⁵ It is uniquely paradigmatic since it is “beyond οὐσία.”Footnote ⁵⁶ The first principle is the goal precisely because of its unique paradigmatic status.

The principal alternative to Plato’s assumption of the dual aspect of nature is this. Someone with a human endowment fulfills his or her nature every day no matter what he or she does. On this view, it is a mistake to separate endowment and achievement normatively. On this view, it would still be possible to retain a distinction between first and second actuality, but the latter would have no normative significance. Even if there were a Form of Humanity, there is nothing we could do, short of dying, that would cause us to divest ourselves of our natural bodily endowment. We are fulfilling our nature at every moment. So, whatever good we seek is bound to diverge from a unique and universal first principle of all since that good can only be a function of our idiosyncratic individual desires.Footnote ⁵⁷ On what other basis could I seek my own good? On what other basis could I discover that what appears to me to be my good is in reality not so? For I can have in principle no other guide to my real good than what appears to me to be that.

The basis for Plato’s rejection of this alternative is found in Socrates’ “autobiography” in Phaedo.Footnote ⁵⁸ Naturalistic explanations for things being the way they are and for it being good that things are the way they are as provided by Anaxagoras are inadequate. A turn from naturalistic explanations to metaphysics is required. These sorts of explanation have a natural stopping-point in Forms, but ultimately require a stopping-point in “something adequate (τι ἱκανόν).” For example, if it is asked why Socrates is sitting in prison when he could escape death, the naturalist will provide an explanation in terms of anatomy and physiology whereas Socrates argues that he is remaining in prison because he believes that it is good for him to do so (even though, of course, dying unnaturally is not a good). Leave aside for now the explanations for things and events that stand outside human ethical considerations and appear to have no connection to the Idea of the Good. If it is indeed good for Socrates to remain, without this good being explained ultimately by the Idea of the Good, it is very difficult to see why it is good for Socrates to give up his life as opposed to fleeing and perhaps fighting again another day. But perhaps he believes that it is good for him to remain just because that is the way he is. Perhaps he wants to stay because of some pathological psychological state. If that is the case, then the issue morphs into a question of relativism.

If relativism turns out to be unsustainable, then the desire for the real good for oneself can only be the achievement of one’s nature, the paradigm of which is the Form of Humanity whose paradigm in turn is the Idea of the Good. So, fulfilling one’s nature is to approach the ideal.Footnote ⁵⁹ But the ideal is itself only an ideal expression of the first principle of all. It is only an instrument of the first principle, which exceeds all οὐσίαι in “power (δυνάμει).” It does so because it is uniquely self-explanatory and unlimited in its activity. As we can see in the Divided Line, it is not even possible to know the Forms without “ascending” to the unhypothetical first principle of all.Footnote ⁶⁰ If the good we all seek for ourselves were other than an instance of the Idea of the Good, the first principle of all, then there could in principle be no explanation for why something is really, as opposed to apparently, good for us. For a process of reasoning that led me to conclude that something was really good for me would still leave me with the fact that it can only appear to me that it is really good for me. If it is indeed good for me, that is not because it appears to me to be so. The successful defense of the claim that all human beings seek the real good requires that the real good is identical to the ultimate and “adequate” explanation or αἰτία for the being of anything.

Every Form is, of course, unique. But the uniqueness of the Idea of the Good is not the uniqueness of a Form and that fact should restrain us from taking it to be unequivocally a paradigm, even the “ultimate” paradigm. It is only analogously so. The Good is not eminently all things; if it were, we might be enticed to say that it has the predicate “paradigmatically good.” If that were so, it could only be because the Good participated in another paradigm. It is a paradigm only in the sense that it stands to everything else analogous to the way the real paradigms – the Forms – are paradigms of the intelligible samenesses and differences found in the world. It is virtually everything, analogous to the way that “white” light is virtually all the colors of the spectrum. The relevance of this unique, quasi-paradigmatic status for moral realism is as follows. The Good, although it makes things beneficial or useful, does not provide “content” to things such that when they are good, that is because they participate in that content. The Forms are “Good-like (ἀγαθοειδῆ)” not because they participate in the “content” that is the Good but because their being is the effect of the eternal causal activity of the Good.Footnote ⁶¹ There is, as we shall see later in this chapter, an indirect way in which things participate in the Good by achieving integrative unity according to kind.

The charge frequently made against the interpretation of Plato according to which the Idea of the Good is the focal point of his moral philosophy depends upon the unquestionable truth that the Good is devoid of content in the sense that it is beyond οὐσία and is, therefore, absolutely simple. But for the charge to work, two additional premises are needed, namely, that which is absolutely simple can have no effects and that it cannot be an object either of desire or of thought. The Platonic rebuttal of both of these premises must be the same: The Good or One is essentially productive. It cannot produce what it is incapable of producing. Since it is ultimately the cause of everything, it is capable of producing everything. From the vast and complex array of intelligible beings in the world, we can immediately infer that the Good/One has the power to produce these. That is why it exceeds all intelligible being in its power.Footnote ⁶² The supposed content of which the Good/One is bereft is actually the entire intelligible world, so long as this is understood to be an effect rather than an explanatory terminus. The Good that we all seek must be the Good from which we all come because any putative content sought for other than the Good can always be “deconstructed” as effect and not as cause. As such, the question still remains as to what makes this effect good. The answer to this question is always: the Good in which it partakes. And it is that that we are seeking. The Good is not “empty”; it is the cause of the being of all there is. Its productive causality consists in its “overflowing,” which it does eternally. Everything desires the Good because the Good is the principle of one aspect in the duality of nature, the aspect of achievement. It could only be this if it is also the source, “containing” in itself virtually everything it produces. The Good produces all the things whose goods consist in the fulfillment of their natures, natures which are what the Good is virtually. To achieve one’s end is to arrive at one’s source.

2.4 The Idea of the Good and the Demiurge

In Timaeus, Plato introduces “the maker and father of this universe (τὸν μὲν οὖν ποιητὴν καὶ πατέρα τοῦδε τοῦ παντὸς),” the Demiurge.Footnote ⁶³ This maker is “good (ἀγαθός).”Footnote ⁶⁴ And because he is good, he is not “grudging (φθόνος).”Footnote ⁶⁵ Therefore, he “willed (ἐβουλήθη)” that the cosmos he was about to create should be good, too, as near to being like himself as possible.Footnote ⁶⁶ In fact, he desired that the cosmos should be as good as possible.Footnote ⁶⁷ On the basis of this description alone, many Platonists throughout history have been irresistibly drawn to the conclusion that the Demiurge is to be identified with the Idea of the Good.Footnote ⁶⁸ It is hardly surprising that early Christian Platonists should be drawn to this conclusion, too. The principal reason for this is that if the Demiurge and the Good are conflated, then the Christian God can more plausibly be identified with both.Footnote ⁶⁹ So, God is the first principle of all and God is provident and has or is an intellect. But in Timaeus itself, the text seems implicitly to deny this identification. In the course of a discussion of the principle of necessity and of the world prior to its being made a cosmos, Timaeus says,

Since the Demiurge has already been spoken of extensively, it seems straightforwardly to follow that the Demiurge is not the first principle of all.Footnote ⁷¹ The only thing that might lead us to hesitate in drawing this conclusion is that Timaeus refers to “first principle or principles.” One might suppose that “principles” cannot refer to the first principle and hence not to the Good. But the ambiguity is easily resolved on the basis of Aristotle’s testimony, according to which Plato posited two principles, the One and the Indefinite Dyad, identifying the former with the Good. For our purposes, we can leave aside for now in what sense the Indefinite Dyad is a principle. However exactly it is related to the Good, identified with the One, does not change the fact that the Demiurge is not the unhypothetical first principle of all, and therefore is not God, understood in the Christian sense, nor is he the source of normativity. For he is good, not the Good.Footnote ⁷² Furthermore, because he is an intellect, he has an οὐσία.Footnote ⁷³ And thinking all the Forms contained within the Living Animal means, minimally, that his intellect is informed by these in all their complexity.Footnote ⁷⁴ Hence, he cannot be beyond οὐσία or absolutely simple in the way that the Good must be.

Perhaps the most important consideration militating against the identification of the Demiurge and the Good is this. The Demiurge is required to work on the Receptacle and the precosmic chaos in order to bring about the best possible image of the intelligible world. He is undoubtedly constrained by the circumstances presented to him. He is confronted with “necessity (ἀνάγκη).”Footnote ⁷⁵ He is constrained because he has or is an intellect which is his οὐσία. That is what he is. His οὐσία is, by definition, a principle of limitation: to have an οὐσία is to be this and not that. These constraints indicate, or more accurately, define the nature of the Demiurge. He can do only what he can do with the material at hand because he is the good intellect that he is. Since the Good is beyond οὐσία, there is no way to attribute a definitional limitation to it. To say that it was constrained by the precosmic chaos would be to imply that there is something about its nature or οὐσία that makes this precosmic chaos a constraint on it. So, in addition to the other reasons given above, it seems quite clear that the Demiurge cannot be identified with the Good, the first principle of all.

This leaves us with the question of how the Demiurge is related to the Good and specifically, what role the Demiurge plays in Plato’s moral theory. The refusal to conflate the Demiurge and the Good yields some fairly obvious conclusions.Footnote ⁷⁶ First, providence is not to be attributed to the Good. This is solely within the purview of the Demiurge and the gods he creates.Footnote ⁷⁷ Second, the goodness of the Demiurge means that he is not a principle of normativity, but rather that he conforms to it.Footnote ⁷⁸ So, an investigation of normativity can appeal to the Demiurge as a supreme example of goodness, but he himself is only an example. His goodness is not self-explanatory; it is derived. Third, such “personal” attributes as the Demiurge has, including being ungrudging and desirous of the goodness of his creation and deliberating about how to achieve his goal, do not belong to the first principle of all. It is true that the Good is called in Republic “most happy (εὐδαιμονέστατον).”Footnote ⁷⁹ But this term does not necessarily indicate anything personal. The most salient feature of happiness in Greek thought is self-sufficiency, and though this is typically attributable to persons or gods, it is not implausible that the self-sufficiency of the Good follows from its absolute simplicity, not from its having attained whatever it needs, since it is impossible that the Good needs anything.Footnote ⁸⁰ It is precisely the absence of absolute simplicity that produces insufficiency, especially in such things, like human beings, in whom there is a gap between endowment and achievement and in whom ungrudgingness is an achievement not an endowment.

If the Demiurge is irreducible to the Idea of the Good, this fact raises the obvious question of what purpose the Demiurge serves. The principal one seems to be to account for the order or intelligibility of the cosmos.Footnote ⁸¹ This is what νοῦς and only νοῦς is able to do. The cosmos is intelligible to us because intelligibility was put into it by an intellect. Intelligibility is essentially communication among or between intellects. That is what “dia-logue (διά-λόγος)” is. The Good alone cannot account for this because the Good does not have intelligibility strictly speaking, that is, it is not an οὐσία. The Demiurge is the locus of all intelligibility represented by the Living Animal which it eternally contemplates.Footnote ⁸²

The point of all this for moral theory is that while knowledge (ἐπιστήμη) may in some sense be both necessary and sufficient for virtue, this is only the case if that knowledge somehow reaches beyond the intelligible Forms and beyond the Demiurge to the Good itself. The Good does not just make the Forms to be the intelligible entities that they are but it also makes them knowable and makes participating in them beneficial. The normativity of moral realism is mostly a bluff or a charade without the superordinate Good. This is the lesson of the Divided Line and the surrounding texts in Book 6 of Republic. Hence, desiring the real, as opposed to the apparent, good requires that there exists a real Good over and above all the Forms. The role of Forms is instrumental to the imposition of normativity in nature, as is the νοῦς that effects the imposition. It is never sufficient to know what the Form of Justice is. It is also necessary to know that being just is one way to instantiate the Good. If anyone desires anything, it is because it is a prima facie manifestation of the Good.

What is true for the Demiurge is, a fortiori, true for the gods he generates. These gods are two removes from the principle of normativity. Their being providential and benevolent, as explained in Laws Book 10, is not because they are normatively or ontologically fundamental but because, like all living things, they desire the Good and are themselves good insofar as they achieve what they desire.Footnote ⁸³ Hence the old chestnut, deriving from Euthyphro, which inquires whether something is good because the gods desire it or the gods desire it because it is good, is answered decisively by the latter alternative.Footnote ⁸⁴ The gods do not make virtue good by loving virtue or practicing it. These gods are powers in the cosmos, obviously more powerful than us since they are immortal. But they are not determinants of what is good and evil. And insofar as they can be imagined to be involved in punishing the wicked and rewarding the virtuous, they are servants of the well-run cosmos instituted by the Demiurge. In the matter of ethics, Plato draws his principles from metaphysics, not from theology.

2.5 Assimilation to God

In the so-called digression in Theaetetus, Socrates delivers an exhortation to the distinguished mathematician Theodorus regarding the aims of philosophy.

For ancient students of Plato, the words “assimilation to god (ὁμοίωσις θεῷ)” express pithily the culmination of Plato’s ethics.Footnote ⁸⁶ The flight from evils is in the direction of the Good; it is the return to the source, as we have just seen. That flight consists in the practice of virtue with the addition of wisdom, precisely the wisdom that was absent in the man in Republic Book 10 who was virtuous merely by “custom (ἔθει)” “without philosophy (ἄνευ φιλοσοφίας).”Footnote ⁸⁷ It is clear from this passage, however, that fleeing toward the Good does not mean something like a mystical union with it. The successful flight puts one in the company of the god or gods who themselves are subordinated to the Good. That this is the result follows from the nature of the assimilation, or more literally, the “making the same as.” For one does not transcend οὐσία by the assimilation; on the contrary, one reverts to or appropriates one’s own divine nature. That nature is the nature of an intellect, eternally contemplating intelligible being. Thus, we are made to be like the Demiurge by engaging in intellectual activity. And, as is also the desire of the Demiurge, we are made like the Living Animal by being cognitively identical with all the Forms it contains. That is, for example, the only way that an intellect can be made to be the same as a hippopotamus or a triangle.

In light of the Republic passage, we are obliged to say that wisdom or philosophy is an essential addition to virtue in order for assimilation to occur. Why? A by-now-venerable answer to this question is that the knowledge is an essential addition because this knowledge reveals how to be virtuous or how to put virtue into practice. It is the knowledge of a τέχνη. This interpretation is unsupportable for several reasons. First, as Republic Book 10 shows, the character without philosophy who chooses the life of a tyrant is already virtuous. That he is so by custom does not change the fact that he is not in need of knowledge of a τέχνη of how to do virtuous deeds. If it is objected that what he needs is not this sort of knowledge, but the knowledge of how to be virtuous, that is, how to have a virtuous disposition, it is far from clear what sort of τέχνη this is supposed to be.Footnote ⁸⁸ The knowledge that, added to virtue, makes one like the gods, and that turns mere virtuous behavior into true virtue, is the knowledge that philosophers seek in Republic and in Symposium. It is knowledge of the Good, which is not esoteric knowledge of some secret “content,” but knowledge that the Good is the One, virtually all intelligible being. Knowing that the Good or One is universal, we at least know that our happiness, our real good, cannot be achieved at the expense of anyone else. Practicing ordinary or “demotic” virtue is a simple and useful technique that contributes to achieving this goal. But it could never be sufficient without the knowledge – not belief – that one’s own good is the good of an intellect, not that of an embodied human being. This knowledge is not otherwise available to human beings than as the culmination of philosophical education and it alone results in the self-transformation that consists in “becoming one out of many.”Footnote ⁸⁹ And it follows from the possession of this knowledge that one’s true good cannot be achieved at the expense of anyone else.

2.6 The Idea of the Good and Erōs

Seen in the light of all the above, Diotima’s speech in Symposium takes on a new clarity. Diotima instructs Socrates that love (ἔρως) is for beautiful things (τῶν καλῶν).Footnote ⁹⁰ But this amounts to, says Diotima, a love for good things (τῶν ἀγαθῶν), that is, the possession of good things.Footnote ⁹¹ And the result of possessing good things is happiness (εὐδαιμονία), which all human beings wish for (βούλεσθαι).Footnote ⁹² So, love is nothing but the desire or appetite (ἐπιθυμία) for good things or for happiness.Footnote ⁹³ The nexus of concepts here follows without deviation from what we have already seen in Gorgias and Republic. We all desire what is in fact good for ourselves and nothing else. A sharp distinction needs to be made between the things that seem or appear to be good for ourselves but are not and the things that really are. What Symposium adds is the extraordinary identification of the desire for good things with the love of beautiful things.Footnote ⁹⁴ Ἔρως evidently includes both the desire for the apparently beautiful and the desire for the really beautiful. This last point is a crucial part of the puzzle since the cycle – remaining (μονή), procession (πρόοδος), and reversion (ἐπιστροφή) – needs to include everything there is.Footnote ⁹⁵ No one does not desire to possess manifestations of the Good insofar as this is possible. But people, including lovers and tyrants and ordinary folk, do not frame their desires in this way. The answer to the objection that not all desire the Good by their own showing is that ἔρως is a common feature of all living things and ἔρως is nothing but a desire to possess the beautiful (whether merely apparent or real), which is in fact identical with a desire for good things. People desire the apparently beautiful because they suppose that it is really good.

The representation of ἔρως as midway between immortal and mortal – a daemon – is quite explicitly intended to establish its unifying role. “Being in the middle of the two [immortal and mortal], they [daemons] complete the whole and bind fast the all to itself .”Footnote ⁹⁶ Love is essentially a unificatory process like higher cognition.Footnote ⁹⁷ In fact, as we learn at the completion of the higher mysteries, the highest expression of love is the highest form of cognition. And, of course, this is why the philosopher is the quintessential lover and why philosophy uniquely has the unificatory and transforming effect on the person.Footnote ⁹⁸

Another important feature of Diotima’s discourse is her claim that the work (ἔργον) of love is birth in beauty, whether in body or soul.Footnote ⁹⁹ It is misleading to translate ἔργον as “object” or “goal” as if ἔργον were synonymous with τέλος. For artifacts, the working or operation of that artifact may well be equivalent to its goal. The question “what does it do?” can be equivalent to the question “what is it for?” but this is not the case for things that exist by nature. The ἔργον of a human being is rational living; the τέλος of a human being is happiness. These are of course closely related, though nonetheless not identical since in the dual aspect of nature, rationality is an endowment whereas happiness is an achievement. What ἔρως does is give birth in beauty or, more expansively, in the presence of the beautiful. The τέλος of ἔρως is, as we have already seen, different; it is the possession of good things or happiness.Footnote ¹⁰⁰ That ἔρως is naturally productive is a crucial feature of the entire system. For the Good is eternally productive and eternally happy, that is, self-sufficient. So, possession of the Good or any manifestation of it has the result of being productive.Footnote ¹⁰¹ It is an indication of the Good’s universal causal scope that the vast variety of natural desires all result, with their satisfaction, in production.

But in addition to the differences between beautiful things, the difference between the apparently beautiful and the really beautiful matters to what is produced. That is why only the philosophical lover, when possessing the Good, produces true virtue.Footnote ¹⁰² Everyone else produces at best images of virtue or, at a further remove, images of themselves.Footnote ¹⁰³ The possession of the Good that produces true virtue is, of course, the knowledge of τὸ καλόν.Footnote ¹⁰⁴ This knowledge or vision is usually understood to be a reference to the Form of the Beautiful, although the question of why this Form alone should produce true virtue is rarely asked. Would not knowledge of a Form of Virtue or of the individual Forms of the Virtues be a more plausible object of knowledge productive of true virtue? We have, though, already had the claim that makes it implausible to say that the philosophers’ achievement of the object of his love is a single Form. The love of beautiful things is nothing but the love of good things. And every Form is good insofar as it participates in the Good. It seems much more plausible to suppose that τὸ καλόν should be read attributively, that is, as a sort of synecdoche, “that which is beautiful,” referring to all the Forms or to Being. Knowledge of Forms as requiting the love of beautiful things only makes sense, I believe, if the Good is virtually all of these.Footnote ¹⁰⁵ If this were not the case, then the achievement of the philosopher would not clearly entail the possession of good things where “possession” indicates the real good that everyone wills (βούλεσθαι).

The production of true virtue which results only from the knowledge of Being further elucidates the articulation of the system. The Good is essentially diffusive. What it produces is unqualifiedly Good-like including both the Demiurge and Being. Here there is no virtue, but only the paradigm of virtue. True virtue is what goodness looks like in the sensible, temporalized, and transitory world. “Illusory” or “popular or political” virtue are deviations from this.Footnote ¹⁰⁶ The reason why wisdom is required to be added to the moral virtues in order to “assimilate to the divine” is clear. So, too, is the reason why “being virtuous without philosophy” in Republic Book 10 is as likely as not to produce dolorous results.

Beauty is a relational property of Being, specifically, the property of attracting us or stimulating our desire.Footnote ¹⁰⁷ Considered as a unity along with symmetry and truth, it comprises the triad that best represents the Good.Footnote ¹⁰⁸ The love of the beautiful encapsulates the reversion to the Good. Accordingly, the multiple beautiful things encapsulate the variety of manifestations of the Good.Footnote ¹⁰⁹ The distinction between appearance and reality works in parallel for both: Apparent beauty stands to real beauty as apparent good stands to real good. Presumably, the prevalence of nonveridical appearances is entirely the result of embodiment. Whatever appears beautiful or good has to be scrutinized by intellect as to its bona fides. Integrated unity is an index of realness as opposed to mere appearance.Footnote ¹¹⁰

Plato, I suppose, focused on the ubiquity of ἔρως to indicate the transcendent and ultimate power of the Idea of the Good. This ubiquity is the best way of acknowledging that the universal desire for the Good must originate in it. Plato saw that the immediate object of ἔρως, the beautiful, is a manifestation of the Good, whether real or apparent. If beauty is a relational property of Being, it follows that love of the beautiful is nothing but the desire for Being, which in turn is, in the consummation of love, just how the desire for the real Good is satisfied. If someone confines himself to the merely apparently beautiful (that is, the nonveridical appearance), none of these facts change. But in that case, it is not possible or perhaps just not likely for someone to grasp that “good is one,” that one’s good is not a goal in a zero-sum game. The charge that, in the higher mysteries of Symposium, the philosopher transcends that the personal is not a charge entirely without merit, though it is ultimately misplaced. For transcending the idiosyncratic personhood of the other is no more necessary than is transcending one’s own idiosyncratic personhood, supposedly constituted by idiosyncratic and incommensurable goods. The one who wonders whether the good that is virtue is beneficial or more beneficial than any other good is assuming that the criterion for an answer to this question is personal advantage. One who is no longer tempted to think that personal advantage can be achieved despite the advantage of anyone else has transformed the personal and thereby achieved real happiness.

2.7 The Idea of the Good and to philon

Plato’s dialogue Lysis, devoted to the theme of friendship (φιλία), can be read as a companion to Symposium.Footnote ¹¹¹ It introduces φιλία into the structure of moral realism just as Symposium introduces ἔρως.Footnote ¹¹² One well-trodden path used in explaining how this is done focuses on an important passage near the end of the dialogue, in which the idea of a πρῶτον φίλον (“primary friend”) is introduced.Footnote ¹¹³ According to this approach, the πρῶτον φίλον is a reference to the Idea of the Good.Footnote ¹¹⁴ This view is sometimes misrepresented as holding that Plato hereby introduces Forms into his discussion of φιλία, not a Form of Friendship, but a Form of the Good or perhaps a Form of Beauty.Footnote ¹¹⁵ As argued above in Section 2.2, Plato distinguishes a superordinate Idea of the Good from a generic Form of the Good. And as I shall try to show now, and in the light of Symposium, we should insist on the likelihood that the πρῶτον φίλον refers to the former and not the latter. Here is the relevant passage:

Clearly, the issue here is the identity of the πρῶτον φίλον.Footnote ¹¹⁷ Perhaps the most obvious answer to this question is: the person who is dear or φίλον, not for utilitarian reasons, but for “his own sake.” The most well-known proponent of this view is Gregory Vlastos, who argued that “loving someone for his own sake” means to love them without regard for one’s own sake.Footnote ¹¹⁸ As I have already argued in this chapter, the dichotomy between “for another’s sake” or “for one’s own sake” is undercut by the identification of the Good and one’s own good, meaning not that the Good just is my own good or your own good distributively, but that their identity guarantees that it is not possible that my own good should be achieved at your expense. If that is so, then it is pointless to contrast altruism with egotism. Your good is never betrayed as I successfully seek my own, nor is my good betrayed when you are seeking yours. Needless to say, this claim applies only to the real good. Obviously, it frequently appears to one that one’s own good is at odds with the good of another, even if this cannot possibly be so.Footnote ¹¹⁹

It might be objected that the universality of the Good thus understood does not in fact efface the contrast between egotism and altruism. On the contrary, it is possible to be selfish and to be unselfish. These are real motives for action. Plato’s moral realism does not deny this. Every ostensibly selfish or altruistic act appears to the agent to be a manifestation of the Good that she seeks. If that act turns out in fact to be good, then it is good for the agent and for everyone else that it is good for the agent. The implication of Plato’s position is that describing an act merely as egotistic or altruistic does not give us enough information to be able to determine whether the appearance of good in this case (to the agent) is veridical or nonveridical. People certainly do act selflessly and selfishly. But in each case, the act takes its characterization from the rational desire or intention of the agent. Among other things, the metaphysical foundation of ethics undercuts the assumption that such desires or intentions are dispositive with regard to the question of the instantiation of the Good.

A different proposal is advanced by Terry Penner and Christopher Rowe, who argue that the πρῶτον φίλον is knowledge, that is, knowledge of whatever it is that would produce my maximal happiness at this moment and under these circumstances.Footnote ¹²⁰ Without wishing to discount the importance that Socrates places on knowledge, it seems far-fetched, to say the least, to focus on knowledge as the πρῶτον φίλον as opposed to what knowledge is supposed to be of. If that is so, “whatever maximized my happiness” would be the πρῶτον φίλον. But this result faces a problem alluded to earlier, namely, that it does not exclude the possibility that my happiness should be achieved at your expense. If, however, it is stipulated that it does exclude this possibility, then this would be because my happiness and your happiness are the same thing, not numerically, of course, but in principle. My argument has been that the only way this could be so – apart from sheer unaccountable luck – is if the Good is uniquely beyond οὐσία. That surely is the πρῶτον φίλον, knowledge of which is, as Republic makes explicit, and Symposium supports, what produces true virtue in everyone and anyone.Footnote ¹²¹

In Lysis, ἐπιθυμία of what we lack is the cause of φιλία; in Symposium, ἐπιθυμία of what we lack is the cause of ἔρως.Footnote ¹²² And what we lack and so desire is, nevertheless, οἰκεῖον to us.Footnote ¹²³ Further, our desire for the Good is desire for it as beautiful (καλόν).Footnote ¹²⁴ Penner and Rowe are right to recognize that knowledge is the achievement of what is οἰκεῖον to us. And they are also right to emphasize the importance of being able to apply this knowledge to our own lives. But the Good is not the knowledge; rather, it is what the knowledge is of. And this Good is a metaphysical principle, not its contingent instantiation. Indeed, without the metaphysical principle, there could be no instantiation of it at all.

The last line of our passage makes the important point that the things that we think are φίλον because they are instrumental to the πρῶτον φίλον would only be deceptive images if there were no first. In other words, something derives its character of being φίλον from the first. Why, though, would we ever be in danger of being deceived by things that are φίλον but not the first? Within the metaphysical framework already adduced, there is a readily intelligible answer to this question. It is that if you do not grasp anything supposedly φίλον as related to the first, then you are likely to be deceived by it because the features of it that you identify as making it φίλον are in fact misidentified or misleading. If, to recur to Symposium once again, you identify beauty with certain physical features, the deception would be in thinking that something without those features could not be beautiful. This does not mean that the thing deemed beautiful is not so; it means only that unless you see it as an instance of the Form of Beauty, you will be misled – perhaps disastrously misled – in how you respond to that. So, unless you acknowledge the πρῶτον φίλον, and therefore, that every other thing said to be φίλον is δεύτερον (secondarily) φίλον and φίλον at all only because it participates in the first, you are likely to be deceived.Footnote ¹²⁵

In Republic, philosophers are distinguished from “lovers of sights and sounds” not by their knowledge – after all, they are seeking knowledge, not proud possessors of it – but by the fact that they understand that knowledge has as objects the intelligible world of which the sensible world is only an image.Footnote ¹²⁶ Philosophers do not mistake the sensible world for the really real world. What this means in practice is that they will not misconstrue images of the real for the real itself; they will not take the “material” out of which the images are constructed as constitutive of the essential structure of the real. The false dialectic of the nonphilosopher is even more vividly at play when a secondary φίλον is mistaken for a primary one. The mistake consists in a doomed exploration of what exactly it is that makes the φίλον so. It is doomed because it presumes to find the answer in, as Vlastos puts it, “the individual as love object.” The idiosyncratic attributes of the individual are not illusory or even insignificant. After all, even the apparently beautiful attracts us to the Good. But these idiosyncratic attributes cannot amount to what the πρῶτον φίλον is. Loving persons as individuals or “for themselves” is no more excluded from the moral realism developed here than is altruism. Nevertheless, there is a fundamental divide between the love of persons as a function of the love of the πρῶτον φίλον and the love of persons as a substitute for that.

The dialogue Lysis, whatever its compositional place is in relation to Symposium and Republic, provides a revealing, albeit limited, account of the logic of transcendence. All desire aims at a goal or τέλος, that which satisfies the desire. The goal is either the πρῶτον φίλον or it is not, in which case it is a means to the πρῶτον φίλον. How are we to tell whether something is just φίλον because it is a means to the πρῶτον φίλον or whether it is itself the πρῶτον φίλον? The criterion provided in the above text is whether we can or cannot say of it “on account of something else (ἕνεκά του).” If we can, it is not the πρῶτον φίλον; if we cannot, it is. The Good is clearly φίλον in the latter sense. The manifestation of the Good in my case is my happiness, just as the manifestation of the Good in your case is your happiness. But if your happiness is subordinated to mine, then your happiness becomes only instrumentally φίλον to me; it is no longer a manifestation of the πρῶτον φίλον. In principle, this is perhaps the way the world works sometimes. It is surely not the way Plato thinks the world works. For the manifestation of the Good in A – let us call it x – is distinguishable from the material out of which x is constructed, just as Helen’s beauty is distinguishable from her flesh and bones.Footnote ¹²⁷ So, if the Good is manifested in how A acts in relation to B, though the λόγος of A’s acting is different from the λόγος of B’s being acted upon, if A’s acting in relation to B is a manifestation of the Good for A, then there is no logical space for its being other than a manifestation of the Good for B. That impossibility would not be like a case of Helen’s flesh and bones being ugly in different circumstances or in comparison to Aphrodite. What makes something a manifestation of the Good is always distinct from the agential circumstances and peculiarities of the agent, even though the Good cannot be manifested in us other than through our agential circumstances and peculiarities.

The result is that the πρῶτον φίλον must be over and above any manifestation of it. But unlike, say, the Form of Justice, it cannot have any essentialistic content. For on the assumption that it had such a content, one could always ask whether that content is good, that is, if the presence of that content is just φίλον “on account of something else” or the πρῶτον φίλον. If the prudentialist wants to maintain that a just act is the πρῶτον φίλον because it is constitutive of one’s happiness, then that act could never be inimical to the happiness of someone else even if that person were indifferent to it. But for all we know, the same could be said for an unjust act when performed by the aspiring tyrant. The only way to short-circuit the realization of this possibility is if the πρῶτον φίλον is super-essentialistic. My happiness manifests the Good if and only if that manifestation cannot simultaneously negate the manifestation in another.

2.8 The Idea of the Good and the One

My principal concern in this section is answering the question, “what does the testimony according to which Plato identified the Idea of the Good with the One contribute to our understanding of Plato’s moral theory?” Those who insist that the answer to this question is “nothing,” seem to me to have an exceedingly weak case. Those who hold this view are inexorably led to say that the superordinate absolutely simple unhypothetical first principle of all has no relevance to Plato’s moral theory because they cannot conceive of how the Good could provide knowability to the Forms, much less be the explanation for their existence and essence. They have no way of explaining how the Good makes Forms useful and beneficial.Footnote ¹²⁸ By contrast, the recognition of the identification of the Good with the One by Plato does give us a powerful and comprehensive way of untying all these knots.Footnote ¹²⁹ Finally, it should be emphasized that this identification has considerable support from the dialogues, apart from the testimony of Aristotle and the indirect tradition.Footnote ¹³⁰

In chapter 6 of Book Α of Metaphysics, Aristotle moves from a survey of Pre-Socratic philosophers to Plato, whose “treatment (πραγματεία)” of ultimate causes is a centerpiece of Aristotle’s dialectical history.Footnote ¹³¹ Aristotle begins by distinguishing the ethical philosophy of the historical Socrates from the metaphysics of Plato, which begins with the positing of separate Forms as the objects of knowledge. He adds that in addition to Forms and sensibles, Plato posited Mathematical Objects, which are “intermediary” between the two.Footnote ¹³² He then reports:

The evidence that Plato did indeed identify Forms with Numbers in some sense is extensive.Footnote ¹³⁴ Aristotle does not introduce this identification as a late “development” in Plato’s thinking; indeed, Aristotle throughout the corpus and the scores of references to Plato’s philosophy never even suggests that that philosophy is not a unified system. The reduction of Forms to Numbers is not presented as a development but rather as an integral part of Plato’s causal analysis.

The testimony continues:

So, Aristotle’s testimony is that the ultimate principles of Plato’s philosophy are the One and the Indefinite Dyad. It is not unreasonable to infer that this One must be another name for the first principle of all, the Idea of the Good. This inference is supported by the following passage:

A number of features in the above report deserve attention. First is the claim that Plato viewed Forms as having elements.Footnote ¹³⁷ Second is that these elements are the One and the Great and Small, also called “the Indefinite Dyad (ἀόριστος δυάς)” as the next passage indicates.Footnote ¹³⁸ The third feature of the above account is Aristotle’s expression of the two principles as matter and essence or form. We must assume that Aristotle knew that the Idea of the Good is specifically said by Plato to be beyond essence. If the Good is the One, in what sense is it the essence in relation to matter? The explicit use of Aristotle’s own terminology to explain Plato’s position both raises a question about the accuracy of the testimony and about Plato’s view regarding the relation of the two principles.

My suggestions for an answer to these questions are, briefly, this. Plato posits the Good and the Indefinite Dyad, later to be reflected in the distinction between Limit and Unlimited in Philebus, as the principles of a sort of Platonic hylomorphism.Footnote ¹³⁹ Plato’s version is to be distinguished from Aristotle’s by the fact that while Aristotle affirms, Plato denies that the essence of a substance is identical with that substance. The One is not the essence of any kind of thing because the One is beyond essence. But it is the principle of essence for the nature of anything.Footnote ¹⁴⁰ An analogous remark can be made for the Indefinite Dyad. The One or Good is certainly not the essence of oneness; rather, things are or belong to one kind rather than another because of the One. The principle of unity or oneness is not one. But without being one, nothing exists as the one thing it is. So, if we can make sense of how the One serves as a principle of Forms, and so indirectly of everything else, we have no reason to deny the accuracy of Aristotle’s testimony.

The identification of the Good with the One is also supported by a fragment from a student of Aristotle, Aristoxenus, in his Elementa Harmonica in which he says that in a public lecture On the Good, Plato defied the expectations of his audience and instead of talking about traditional human goods such as wealth, health, and strength, he discoursed on mathematics, culminating in the claim that Good is one.Footnote ¹⁴¹ These words are most naturally taken to indicate the uniqueness of the Good, so to speak. “Good is one” means that Good is not one and many, as the Forms are said to be. None of the things that manifest the Good thereby “pluralize” it.

The glaring problem in understanding this testimony is not the identification of the Good with the One, but with the postulation of the Indefinite Dyad as a supposedly coordinate principle.Footnote ¹⁴² If the Good/One and the Indefinite Dyad are distinct principles on the identical ontological level, then each must possess sufficient complexity to be distinct from the other. But then the absolute simplicity of the first principle of all is destroyed along with the rationale for positing such a principle in the first place.Footnote ¹⁴³ The interpretive and philosophical choices seem to be either somehow to subordinate the Indefinite Dyad to the Good/One or else to subordinate both the Indefinite Dyad and the Good/One as coordinate principles of the Form Numbers to another superordinate Good/One. In the latter case, we can maintain the interpretation of the first hypothesis (H1) of the second part of Parmenides as referring to a remote, uncognizable first principle and the second hypothesis (H2) as referring to the One-Being and its coordinate Indefinite Dyad.

The path to a solution to this problem should begin with a recognition that the Indefinite Dyad has its own sort of unity. It has a unity which nevertheless entails complexity of some sort since the One is uniquely simple. And it is the One’s simplicity that entails its absolute priority. Accordingly, the Indefinite Dyad cannot be really coordinated with the primary One.Footnote ¹⁴⁴ The Indefinite Dyad is a coordinate principle of One-Being, but the first principle of all is beyond Being. Undoubtedly, this alternative involves its own severe problems.Footnote ¹⁴⁵

Why, though, is the Indefinite Dyad a principle at all? The simple answer is that the Indefinite Dyad is the principle of πλῆθος or magnitude or size, which includes both continuous and discrete quantities.Footnote ¹⁴⁶ With the principle of number alone, there could be no lines or planes or solid figures.Footnote ¹⁴⁷ So, the apparent paradox facing Plato is this: If everything is generated from the One, then so is the Indefinite Dyad. But magnitude cannot be generated from the One. For example, a line is not generated from a point or an aggregation of points. The paradox is mitigated to a certain extent by the fact that One-Being is not number, but the principle of number, in which case number is generated from One-Being as much as is magnitude. This is why number and magnitude are both generated in H2 of Parmenides. They are coordinate principles of One-Being. It is simply not the case that the Indefinite Dyad is coordinate with the One, first principle of all. The general idea, I think, is that generation of Numbers up to the generation of three-dimensional volumes may be conceived of as a geometrical construction eternally carried out and eternally completed by a divine intellect, that is, the Demiurge. Plato does not have to worry about how lines are composed out of points; rather, lines are constructed from a starting-point in thought, planes from a given line, and so on. The ontological hierarchy is manifested by constructive mathematical analysis. The generation of bodies in time is that of an image of this mathematical order. Without the Indefinite Dyad, not only could bodies not exist, but not even their paradigmatic geometrical volumes could exist. Neither could the Mathematical Objects. In fact, without the Indefinite Dyad, there could not even exist that which is minimally complex, that in which existence and essence are distinct. But complexity is, apparently, maximally instantiated. In that case, the One (from H1) and One-Being (from H2), which is composed of the Indefinite Dyad and the array of essences with which an eternal intellect is cognitively identical, must exist.

Aristotle’s testimony regarding the reduction of Forms to the principles of the One and the Indefinite Dyad is, along with the texts in Republic on the Good as unhypothetical first principle of all, the most important piece of evidence for the claim that Plato’s philosophy is systematic.Footnote ¹⁴⁸ This evidence also informs us that the system is a Derivationsystem, hierarchical in terms of logical or substantial proximity to the first principle.Footnote ¹⁴⁹ Simply stated, the greater unity there is, the closer something is to the first principle. And the identification of Good and One means that unity is also an index of goodness, or at least of proximity to the achievement of goodness.

It is often supposed that Plato did at some point in his career identify the Good with the One, but that this is a later development.Footnote ¹⁵⁰ I think it is just as likely that Plato was from his early acquaintance with Pythagoreans in southern Italy inclined to identify the One as the first principle of all and that as he began to think about the ontological foundation of his moral realism, he saw the need to identify the One with a superordinate Good.Footnote ¹⁵¹ Nothing in my overall argument requires that this is the sequence of doctrinal developments. Nevertheless, I suspect that it was well before writing Republic that Plato moved toward the confluence of the Good and the One.