Ethics remained Plato's central concern from the very beginning of his philosophical production to the composition of the late dialogues. His ethical theory is decisively directed towards the pursuit of eudaimonia, or happiness. In the early dialogues, Plato develops the Socratic project of associating virtue with knowledge. His substantial views are examined in the dialogues of the middle period, and in particular in the Republic, where he introduces the tripartite division of both the human soul and the city.

Early Period

In the so-called Socratic dialogues, virtue is understood as that condition of the soul in which various of its virtuous traits are mutually expressed: justice, moderation, valor, wisdom and piety. Virtue is at the same time one and many, for the existence of one virtue in the soul entails by necessity the existence of others.

In the early dialogues, socratic elenchus is made the vehicle for the development of the discussions on ethical matters. Socrates' discussants are usually famous for having virtues that they, eventually, are not in the position to account for. The philosopher's role is to expose their deficiency in defining virtues, and to prove their cognitive inadequacy. His positive contribution is constrained to giving instructions concerning the care of the soul, or insights with regards to the notion of virtue - barren of any theorizations about the good life in general. Often, Socrates and his dramatic partners attempt successive definitions of virtues. The process of definition is the first step towards the theory of Forms. Apparently, the attempt to reach final definitions, even before the introduction of the Forms, betokens a conviction for the existence of stable moral values. For it is obvious that whatever is subsumed in a single definition, it may not be subject to the constant change of the empirical world.

Virtue is described, explicitly or implicitly, as knowledge of what is good and what is evil. To be virtuous means to be able to distinguish between good and evil and to act according to that distinction. Knowledge of the good is attained by the art of calculation. The ability to appraise (art of measurement) pleasures and pains correctly discloses what is truly good (Protagoras 356d). Therefore, if virtue pivots on knowledge, then evil results from ignorance. This is the meaning of the socratic doctrine "no body wrongs intentionally". People commit evil because they are unaware of what is good, not because they want to do wrong. The acquisition of knowledge renders someone just, moderate, pious and courageous, and dictates one's act accordingly. Clearly, the acts of an agent are dictated by his cognitive standards. This is the essence of platonic ethics, which is justifiably characterized intellectualist.

If evil is done unintentionally, it follows that "akrasia" (i.e., the commitment of immoral deeds under the yoke of the affections of the soul, and against knowledge of the good) is for Plato impossible. His denouncement of akrasia rests on the postulation that all humans go after the good, for only good is truly beneficial for their soul. Evil is so harmful that it is preferable to suffer than doing what is unjust (Gorgias 469c). Thus, the soul always aims at what is good, undeterred by its irrational desires that often antagonize the commands of reason. The assumption that the moral value of an action hinges on the knowledge or ignorance of the agent forms a determinism that Plato finds hard to suspend even in his late work, where the thesis on unintentional wrongdoing is maintained.

"Now, no one goes willingly toward the bad or what he believes to be bad; neither is it in human nature, so it seems, to want to go toward what one believes to be bad instead of to the good" (Protagoras 358c-d).

In the early dialogues, the good is what is worth taking hold of; it serves as some sort of purpose. In the Apology (30a, 38a), the "greatest good" amounts to caring for the perfection of the soul, conversing about virtue, and examining the human life. The good is indisputably beneficial, but it is not always pleasant. The Gorgias explicitly sets the good apart from the pleasant with the argument that goodness is not involved in every pleasure (478b, 495a-500a). Eudaimonia (or, in other words, living well and doing well) apart from being the most important consideration of humans (Crito 48b), it is also what parents wish for their children (Lysis 207e), and what people aim at by taking possession of good things (Euthydemus 278e, 282a). The way to happiness is that of knowledge and virtue. The Euthydemus claims that the possession of beneficial goods, that is goods put in right use, advances us to eudaimonia. This presupposes that the right use of the goods depends on knowledge. The statement that happy is the virtuous man is expressed, in the Gorgias, without hesitation (507c-e).

Middle Period

In the dialogues of the middle period, Plato cannot rely any longer on successive motions and dismissals of candidate definitions of a virtue. The investigation into ethics advances, and this brings about the demand for a positive response to moral questions. The Republic puts forward justice as the focal ethical and political category. The definition of justice is informed by the examination of the structure of the city, and the extension of this structure onto the human soul. The latter is divided into three parts: the appetitive (epithumêtikon), which induces pleasures and irrational desires; the spirited (thumoeides) upon which emotions rest; and the rational (logistikon), which induces correct judgments and logical convictions, and carries out correct calculations about things (believing in accord with measurement, 602d-603a). The three parts confront each other in ceaseless conflict because their pertinent desires are often contradictory. Order and harmony permeate the just soul when every part serves its purpose under the rule of the rational element.

"One who is just does not allow any part of himself to do the work of another part or allow the various classes within him to meddle with each other. He regulates well what is really his own and rules himself. He puts himself in order, is his own friend, and harmonizes the three parts of himself like three limiting notes in a musical scale […]. He binds together those parts and any others there may be in between, and from having been many things he becomes entirely one, moderate and harmonious" (Republic 443d-e).

By all of the basic virtues, wisdom is coupled with the rational part of the soul, valor with the spirited, and moderation is the consensus of all parts about which one prevails among them. Justice is confirmed as the harmonious arrangement and health of the soul, whereas injustice as disorder and disease. Eudaimonia, as expected, occurs as the condition of the just soul (580a, 588b).

The introduction of the Forms plays an essential part in Plato's attempt to refute the moral relativism propounded by the sophists. Virtues are absolute criteria of moral action by reason of their exalted existence beyond the ever changing empirical world. Therefore, the emergence of justice in the soul or in the city realizes the corresponding Form of Justice. Forms, in being the models for the things of the empirical world, secure stable ethical prototypes upon which the platonic polis can be founded. In addition, they are the object of philosophical investigations; and, thus, they can initiate any radical reformation of the moral and political life.

It is worth noting that the Good, a profoundly moral concept, is also assigned with an important role in platonic metaphysics and knowledge-theory. In the Republic (503 ff.), the Form of the Good is set forth as the ultimate principle of knowledge, ethics and reality. The description of the Good is given only in metaphors; and it is classified in higher rank than the Forms - it transcends being (ibid., 509b). It is also the subject of "dialectics", that is, of the superior to all hierarchically ordered disciplines into which all the candidate rulers of the city must be inducted. Consequently, Plato's educational end is met when the Good is contemplated: thus, the soul is oriented towards the Forms, and therefore it improves in both the cognitive and the moral respects.

Late Period

A turn unto the empirical reality of nature and moral behavior marks Plato's late period. In the Timaeus, the world appears as the product of geometer-God, who meticulously designs the universe in the greatest detail. The perfection of heaven is the model for the imperfect terrestrial world. In this context, the universe parallels the role of the city in the Republic: it is the structural analogue to the cosmic soul - for the nature of the individual soul resembles the nature of the cosmic soul. What is demanded from man is to assimilate the motions of his soul with the prefect motions of the heavenly bodies; this harmonization will enable him to overpass the inherent deficiencies of his mortal existence.

Plato's late turn to the empirical world signifies the departure from the Republic's numinous understanding of the Good to a more realistic conceptualization. In the Philebus, the perfect, self-sufficient and desired good is not identified either with pleasure or understanding. It is, otherwise, discerned in a way of life that consists in the blending of the two. Mixed entities are put forward as products of beauty, balance and harmony. But the catalytic paragon that endows the mixed entities with goodness is measure (64d-e). Conclusively, platonic philosophy, ranging form the early Protagoras to the late Philebus, employs the art of measurement to offset luck, and also as a consistent metaphysical condition of ethics.

Author: Deny Konstantinidi
  • Annas, J. Platonic Ethics. Old and New. Ithaka and London, 1998.
  • Destrée, P., Bobonich, C. eds. Acrasia in Greek Philosophy: From Socrates to Plotinus. Leiden, 2003.
  • Strike, G. , Frede, M. eds. Rationality in Greek Thought. Oxford, 1996.
  • Irwin, T, Plato’s Ethics. New York, Oxford, 1995.
  • Meyer, S.S. Ancient Ethics: A Critical Introduction. London-New York, 2008.
  • Nussbaum, M. C. The fragility of goodness: Luck and Ethics in Greek Tragedy and Philosophy,. Cambridge, 1986.
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