Any argument relies upon some fundamental agreement about the issue being discussed. However great the divide in opinion may be, there must exist at least some similarity in the participants’ manner of viewing the issue if a solution is ever to be reached. Book One of Plato’s Republic features a disagreement between Socrates and Thrasymachus about the nature of justice. The disaccord between their views of the subject is extremely pronounced, but there are certain underlying agreements which guide the course of the debate. One way to evaluate the validity of the arguments involved is to examine whether the assumptions at the root of the argument are in accord with this common ground. By my reading of the dialogue, Socrates’ reply to the first part of Thrasymachus’ definition of justice rests safely upon this common ground, whereas his answer to Thrasymachus’ second definition moves away from this mutually acceptable base, and is injured as a result. In exploring this topic, I intend to examine briefly Thrasymachus’ two-part definition of justice. For each of these parts I will evaluate one Socratic response and discuss it from the perspective of the “craftsman analogy” – an analogy which is initially used by common consent, but which Socrates adapts until its original usage almost disappears.
Thrasymachus’ first definition of justice is easy to state, but it is not so immediately clear how it is to be interpreted. Justice, he claims, is the advantage of the stronger. On its own, such a sentence could imply that what is beneficial to the stronger is just for and therefore, beneficial to the weaker, and Socrates accordingly asks whether this understanding is accurate. Thrasymachus promptly responds in the negative. The interpretation he proceeds to expound upon can be summed up by adapting slightly his original definition: justice is that which obtains the advantage of the stronger. To support this definition, he points to the example of ruling a city. Any ruling class will fashion the laws of the commonwealth with a view to its own benefit, he asserts. Since it is just to obey the law, those who behave justly will be acting for the advantage of the rulers (whom Thrasymachus interchangeably terms “the stronger”).
Socrates makes his first objection at this moment, but I will treat this here only incidentally: merely insofar as it allows us to see why Thrasymachus introduces the craftsman analogy. Socrates objects that rulers are, as humans, bound to make mistakes - to confuse their disadvantage with their advantage on occasion. In this case just obedience to laws would work to the ruler’s disadvantage. Thrasymachus responds promptly, saying that a man who makes a mistake in ruling is not at that moment a ruler in the strict sense, and introduces the craftsman analogy to support this idea. Insofar as a man is a craftsman, he will not make any mistakes; mistakes are rooted in ignorance, and so can only occur when a man’s knowledge of his craft is incomplete. The quandary which Socrates introduces is thus avoided by Thrasymachus’ qualification that errors are never made by rulers as rulers.
Though the analogy works at first to Thrasymachus’ advantage, Socrates promptly turns it against him in a new objection. All arts, he asserts, are exercised with a view to the benefit of the subject rather than to the benefit of the artisan. The doctor employs his medical art for the betterment of the patient, the pilot navigates for the safety of the ship and the sailors, and so forth. Like Thrasymachus, he identifies ruling as an art, and claims that ruling also is exercised with a view to the subjects’ benefit. Throughout the argument, Thrasymachus passively assents to Socrates’ individual points. But as we shall see later, he rejects the conclusion drawn from these.
From an objective viewpoint, one immediately questionable aspect of this argument is Socrates’ idea that ruling is an art in the same sense that medicine and navigation are arts. Despite its potential weakness however, Socrates’ use of the analogy is the one part of the argument which Thrasymachus cannot question without bringing Socrates’ first objection once again into dispute. Thus this definition of ruling forms some part of the common ground I have previously mentioned. Although an objection such as this may affect the objective validity of the argument, it is important to keep in mind the fact that Socrates is not attempting to create an incontestable definition of justice at this point. He is merely answering an invalid argument by demonstrating its weaknesses in terms which correspond to Thrasymachus’ perspective.
Agitated by Socrates’ line of reasoning, Thrasymachus proceeds to blurt out a revised version of his original statement. Thrasymachus claims that injustice is freer and stronger than justice and that it results in a happier life. As in the former definition, he does not consider so much what justice is as what it does; he rates the subject in regards to its advantageousness or lack thereof. Essentially, this definition is an extreme extension of the previous one. Also, the example he uses for support – that of a tyrant made powerful and thus happy through injustice – hearkens back to his initial definition as ruling being the advantage of the stronger. It is clear that Thrasymachus has not been convinced by Socrates’ last argument, despite his apparent agreement with Socrates’ points. He is arguing in different terms, but in actual substance this new development is little more than a bare contradiction of Socrates’ previous argument. He still supposes that the unjust will have the advantage, and does no more than give new evidence to support this view. He essentially declares: “You say that the proper ruler will consider the benefit of his subjects and thus act justly. I say that injustice leads to a happy life and that craftsmen do aim at their own advantage.”
Whereas the weaknesses in Socrates’ previously discussed arguments are more or less excusable, there are several factors in his next argument which make it very controversial. In opening this argument, Socrates asks whether a just man will want to overreach and surpass other just men. The two debaters agree that a just man will deem it proper to surpass the unjust man, but that he will not want to surpass his fellow just man. The unjust man, on the other hand, will want to surpass and get the better of everyone. Now Socrates proceeds to use the craftsman analogy to illustrate his case. With this case Socrates attempts to prove that those who try to overreach their “like” are bad craftsmen. Returning to the specific example of the doctor, he observes that a medical man will not endeavor to outdo another physician, but will want to outdo the non-physician.
One flaw seems to appear at this point in the argument. Socrates, it would seem, has left no place in this for simple ambition here. If the first half of this analogy is true, there is no room for an artist to advance and improve his craft in a just manner, because unless he is unjust, he will not have any ambition to surpass his fellow artists. However this can be answered by a glance back at Thrasymachus’ concept of the artisan “in the strict sense.” No one is an artisan insofar as he is in error, so the true artist will be unable to surpass another true artist: ideally, the artist, insofar as he is an artist, will already exercise his art faultlessly.
Socrates completes this argument by saying that the one who tries to overreach the artist can not have true knowledge of the craft. In other words, true artists will be able to identify one another and to recognize the impossibility of surpassing each other. Since the one who wants to surpass everyone in a specific art must not be an artisan, he is ignorant of this art. Thus, Socrates claims, the unjust man is really ignorant and therefore weak and bad.
There is a marked distinction between this use of the craftsman analogy and former uses. Previously the analogy was used in reference to the “craft” of ruling. This was legitimate in the context primarily because Thrasymachus agreed to this use. Now however, the subject of the analogy is not ruling, but justice. Thrasymachus never explicitly agrees to this switch, and thus when it is made, the analogy no longer rests safely upon the common ground. It is no longer an example accepted by both parties and so its sole justification would have to rest on an objective view of the argument. So we have another important question to examine. That is, can justice be rightly considered a craft? Even if it can in a vague sense, would it be properly analogous to other crafts like medicine or navigation?
There are reasons to support a negative answer to this query. For one thing, it could be argued that justice is more a manner of acting, rather than a craft in its own right. Whereas it is nonsensical to say that one can, for example, read a book medicinally, or in a navigating manner (except perhaps as a figure of speech), one can exercise a craft or perform any action either justly or unjustly. Justice is more easily considered a measure of how well an action is performed than the action itself.
The most important thing to note here is that Socrates has moved away from the common ground which has previously supported the argument. Before, the question of whether Socrates’ examples are objectively valid was not so crucial from one viewpoint. As long as Socrates was trying to demonstrate the illogicalities within Thrasymachus’ position, there was much to gain from arguments based on Thrasymachus’ premises, whether the premises were true or not. For this last argument, however, Socrates does not base his argument on these guides, but preserves the form of the craftsman analogy while changing it substantially. Thus this particular argument suffers and is at least of questionable efficacy.
However, if the question of whether injustice is better than justice were entirely closed here, there would be no need for the rest of the book. Problems in Socrates’ arguments are taken up by new actors in later books of the dialogue, and Socrates will spend nine complete books essentially inquiring into this theme. Though Socrates may be inefficient in answering Thrasymachus’ particular arguments, once we step back to look at The Republic as a whole, it becomes apparent that inconsistencies in Book One provide the necessary fodder to produce the rest of this Socratic discourse.