Plato on Nature, Function, and Virtue

Plato on Nature, Function, and Virtue

In this essay, continue my analysis of Book I of the Republic by examining Plato’s use of the classical concept of excellence to defend the claim that justice is an intrinsic rather than merely instrumental good. After arguing that justice is not, as Thrasymachus contends, merely as the advantage of the stronger, Socrates attempts to convince him that it is more advantageous to be just than unjust. Socrates does this by appealing to the concept of αρετη, a term often translated in English as “Virtue” or “Excellence”. In the classical world, a thing had αρετη, or excellence, to the extent that it had the natural features by which to consummate its natural function. For example, consider first the case of a man-made artifact such a pruning knife. Humans create pruning knives with a particular end in view, e.g. to cut vines in a garden. As a result, the knife will be endowed with a certain set of features by which it can accomplish that function well. For example, the blade will be relatively short, light, and sharp. To the extent that it has these features, the  knife will have αρετη to the extent that it manifests these features. To the extent that it lacks these features or has others that nullify them the knife will fail to be an excellent pruning knife. A dull, long, or heavy blade would lack αρετη since it would not have the requisite characteristics by which to perform its function well. Socrates himself uses this example with Thrasymachus:

“S: Could you use a dagger or a carving knife or lots of other things in pruning a vine? T: Of course. S: But wouldn’t you do a finer job with a pruning knife designed for the purpose than with anything else? T: You would. S: Then you would take pruning to be its function? T: Yes. S: Now, I think you’ll understand what I was asking earlier when I asked whether the function of each thing is what it alone can do or what it does better than anything else. T: I understand, and I think that this is the particular function of each” (Republic 353a-b trans. Cooper).

We make artifacts with a particular end in view, a function “it alone can do or…does better than anything else.” Knives cut, hammers hammer, and screwdrivers screw. And individual instances of these kinds are excellent to the extent that they have the requisite features to fulfill these functions. An excellent knife cuts well, an excellent hammer, hammers well, and an excellent screwdriver screws well.

            So far this likely all seems commonsensical.  Yet the classical conception of αρετη can begin to sound strange to contemporary ears when applied to the natural world. We can accept that man-made objects can have functions, since we give them those functions. But, without our activity, natural objects are in themselves meaningless. Considered in itself, a piece of flint, for example, has no function. It is only after a caveman has determined that it should be a knife and sharpens it into one, that the stone takes on the function of cutting. The knife has a meaning only because man assigns meaning to it. Indeed, the only meaning to be found anywhere in the universe is the meaning we give to it. Après moi, le deluge! All this sounds very familiar, living in an age where existentialism has colonized the popular consciousness, but this perspective is foreign to the classical mind. For, from a classical point of view, the universe is essentially meaningful and natural kinds have natural functions. Indeed, it is just this natural order that establishes the normative standard by which to judge the actions and characters of men. Consider again the conversation between Socrates and Thrasymachus:

“S: Tell me, do you think there is such a thing as the function of a horse? T: I do. S: And would you define the function of a horse or of anything else as that which one can do only with it or best with it? T: I don’t understand. S: Let me put it this way: Is it possible to see with anything other than the eyes? T: Certainly not. S: Or hear with anything other than ears? T: No. S: Then, we are right to say that seeing and hearing are functions of eyes and ears? T: Of course” (Republic 352e).

Socrates here points out that natural objects have functions. Consider the eye, its function is to see. If an eye was structured in such a way that an animal could not see with it in normal environmental conditions, we would say that eye was somehow defective. There would be something wrong with it that prevents it from carrying out its natural function. The same holds for organisms. One function of a horse, for example, is running. If it was born with a deformity or one of its legs was broken, something would be wrong with it. Such a crippled horse would be a defective instance of horseness. It would soon be eaten by predators and would fail to manifest the beauty intrinsic to its natural kind. Note that, to the Greek mind, this function is not bestowed on horses externally as artifacts constructed by God as some kind of cosmic engineer.[1] Rather, a horse’s natural functions are determined by its essence as a horse. Natural kinds have intrinsic meanings purely in virtue of being the kinds of things they are. Plato will give a fuller account of what he takes such essences to be and how they are grounded later in the Republic, but, for now, it’s sufficient to note the fact that, from a classical viewpoint, things have essences and these essences determine their proper function. The study of how essences ground what a given thing is meant to do is called teleology, coming from the word τελος meaning achievement, attainment, or goal. The ancient Greeks thus lived in a teleological world. There are certain activities particular beings ought to do simply in virtue of being the kinds of beings that they are. A natural kind sets the standards of excellence for its instances. A panda would fail to be an excellent panda if its jaw was broken and couldn’t eat bamboo, a horse without legs would not be an excellent horse, and a wingless eagle would fail to be an excellent instance of its kind.

            Thus, to the classical mind, virtue and vice are grounded in nature. The virtuous are those that have what it takes to allow them to achieve the τελος encoded in their natural kind, and the vicious are those that lack it. Socrates explains:

“S: And could eyes perform their function well if they lacked their peculiar virtue and had the vice instead? T: How could they, for don’t you mean if they had blindness instead of sight? S: Whatever their virtue is, for I’m not now asking about that but about whether anything that has a function performs it well by means of its own peculiar virtue and badly by means of its vice? T: That’s true, it does. S: So ears, too, deprived of their own virtue, perform their function badly? T: That’s right. S: And the same could be said about everything else? T: So it seems.” (Republic 353c-d).

Blind eyes and deaf ears lack virtue, since they cannot carry out their natural functions. Whereas seeing eyes and hearing ears are virtuous, being able to fulfill their natural functions.

Socrates then uses this framework to attempt to convince Thrasymachus that justice is more advantageous than injustice. He does this by asking Thrasymachus to consider the soul as a natural kind. He queries:

“S: Come, then, and let’s consider this: is there some function of a soul that you couldn’t perform with anything else, for example, taking care of things, ruling, deliberating, and the like? Is there anything other than a soul to which you could rightly assign these, and say that they are its peculiar function? T: No, none of them. S: What of living? Isn’t that a function of the soul? T: It certainly is. S: And don’t we also say that there is a virtue of a soul? T: We do. S: Then, will a soul ever perform its function well, Thrasymachus, if it is deprived of its own peculiar virtue, or is that impossible?           T: It’s impossible ” (Republic 353d-e).

Socrates here maintains that living is the function unique to the soul as a natural kind. The soul, according to Socrates, is that in virtue of which living things live. For example, pandas are alive because of their souls, and so is the bamboo they eat, and so are we who think about them both. If this is true, then a soul with αρετη will have what is needed to live, while a soul without it will not. Furthermore, Socrates observes that justice is a virtue of the soul and injustice a vice. Thus, “it follows that a just soul and a just man will live well, and an unjust one badly” (353e). And the one who lives well is “blessed and happy”, and those who do not are the opposite (354a). So, “a just person is happy, and an unjust one wretched” (354a). And, since “it profits no one to be wretched but to be happy”, “injustice is never more profitable than justice” (354a).

Although there is something to this brief argument, and it suffices to quiet Thrasymachus for the moment, one is left with the feeling that more work is needed. Indeed, this is precisely the case that Glaucon and Adeimantus will make in Book II as they try to bolster Thrasymachus’s position and force Socrates to give a more elaborate argument for the claim that justice is an intrinsic rather than merely instrumental good. We’ll examine these issues next time, but for now I’d like to invite you to reflect on the classical concept of αρετη. If natural kinds have natural functions, what is the natural function of man? What would an excellent man or woman consist in? What can we alone do, or at least can do better than any other creature? And, if you have a sense for what that is, how do you measure up to that standard? What steps can you take to move closer to fulfilling your specifically human τελος? These are questions that Aristotle would later ponder in his Nicomachean Ethics. For him, distinctly human excellence consisted in Reason. I’ll leave you with his thoughts:

“Presumably, however, to say that happiness is the chief good seems a platitude, and a clearer account of what it is still desired. This might perhaps be given, if we could first ascertain the function of man. For just as for a flute-player, a sculptor, or an artist, and, in general, for all things that have a function or activity, the good and the ‘well’ is thought to reside in the function, so would it seem to be for man, if he has a function. Have the carpenter, then, and the tanner certain functions or activities, and has man none? Is he born without a function? Or as eye, hand, foot, and in general each of the parts evidently has a function, may one lay it down that man similarly has a function apart from all these? What then can this be? Life seems to be common even to plants, but we are seeking what is peculiar to man. Let us exclude, therefore, the life of nutrition and growth. Next there would be a life of perception, but it also seems to be common even to the horse, the ox, and every animal. There remains, then, an active life of the element that has a rational principle; of this, one part has such a principle in the sense of being obedient to one, the other in the sense of possessing one and exercising thought” (Nicomachean Ethics 1.7 trans. Ross).

For Aristotle, then, as for Plato, humans like all other living beings, have a natural function. Like them we live biologically, but our life encompasses much more. And, like other intelligent animals, we perceive and act adroitly in our environment, but again, our intelligence exceeds the mere perceptual problem solving necessary for survival. What we have, suggests Aristotle, is Reason, the faculty by which we might grasp the meaning and order of the universe in which we live, move, and have our being.

Peter Yong, Ph.D.

[The image used in the thumbnail of this post is Jacques-Louis David’s “Napoleon Crossing the Alps”. It is in the public domain and can be found here: ]

[1] This is one of the many mistakes Sartre makes in his famous essay “Existentialism is a Humanism”. He conceives of meaning exclusively in terms of the functionality of man-made artefacts. If meanings are externally bestowed by the decree of a divine engineer, then then atheism regarding that engineer, eliminates the source of all meanings. Furthermore, if functions are conceived of purely in terms of artifacts it conflicts with free will. Human beings become mere hammers designed to do one things. The classical concept of function avoids both of these problems.

Leave a Reply

Your email address will not be published. Required fields are marked *