The Republic Book 4
At this point, Adeimantus interrupts and asks Socrates what he would say if his people were not happy, as it would be the fault of the city that does not allow them money to travel, or mansions, or treasure and jewelry. Socrates replies that he is trying to mold a city where most of the population is happy, and not where there are a few people who are extraordinarily happy. Furthermore, the reason the city came into existence was for justice, not pleasure and happiness. Also, Socrates examines the effect of wealth on craftsmen, and states that if a potter gets rich, he will not be concerned for his craft and will become lazy and a bad potter; whereas if he remains poor, he cannot afford the tools needed to become a good potter. Thus, both wealth and poverty cause bad work and workmen, and it should be the duty of the guardians to prevent these from coming into the city.
With respect to the actuality of war, Socrates says that the athletes of this city will be better trained to fight a war than that of rich cities, where the warriors will be rich and lazy. Furthermore, since they are not interested in gold, they can easily lure one city into joining them if they have to fight another, by saying that all the material rewards will be given to those who help them. However, there should be no wars within the city. Therefore, when the city reaches its maximum capacity without fighting the rulers should fix it as its limit and let everybody else go. In this case, the command to the guardians will be: "make sure that the city is neither small nor seemingly great, but sufficient and one." Book 4, pg. 90, line 423c As for marketplace squabbles, they will not be worth the while of the citizens, all of whom have had remarkable educations and upbringings, and who will find these things trivial. After stating that the only things left to build are the temples, sacrifices, and other sacred services for the gods, which they do not understand, and about which they will not listen to anyone but the Delphic god, Socrates claims the city has been built.
Now the men attempt to distinguish the justice in the city from the injustice. The first thing they come across is wisdom, but they recognize that it comes from good judgment, which is clearly a kind of knowledge. Thus, men make good judgments because of knowledge rather than ignorance.
However, this knowledge needs to be whole, rather than just for one skill, and so it is established that it belongs with the smallest group of people: the guardians. Next, they try to find where the city's courage comes from. Defining courage as the "power to preserve under all circumstances the right, lawful opinion of what is and is not to be feared" Book 4, pg. 97, line 430, they find that the people in the city who exhibit this behavior are the guardians.
Moving on to temperance, they define it as a kind of control over certain desires and pleasures. Thus, a 'temperate' man is a master of himself. This means that a man's good part rules over the bad part of his soul. Similarly, in the city, the better rules over the worse, and thus the city must be 'temperate' and 'mistress of herself'. Next, they assume that it is the women, children, slaves, and 'free men' who make the lesser part of the city, whereas those people who are guided by reason, along with intelligence and right opinion are the better few. Thus, "the desires of the worthless many are controlled by the desires and knowledge of the decent few" Book 4, pg. 98, line 431d, and because this is temperate city the many recognize the few as better. With this in mind, it can be assumed that everybody in this city will have the same opinion of who should rule. This results in temperance existing among all people; thus temperance resembles harmony, since there is agreement in all parts.
The last excellence in the city, therefore, must be justice, and Socrates and his companions come to find that this is simply tending to your own business. This is because this, in turn, will lead to wisdom, temperance, and courage.
Furthermore, since it was decided that each man is only truly good at one thing, if a person tries to meddle in affairs that are not his own, he will be doing something without any skill, and this will lead to weakness in the city, and eventually the city's death. Doing something that can harm the city is doing something wrong, and therefore injustice. By turning this around, it can be found that justice would be minding your own business. However, to examine justice on the individual level, it must first be found whether the soul has the same three levels as the city. Since the attributes of a city must arise from its people, it can safely be assumed that individuals do have these same levels.
However, Socrates insists that they further examine the soul to see whether it acts as a whole or whether there is a part for learning, a part for feeling emotions, and a part for desiring pleasure, nourishment and the like. They examine this with the idea that the same thing cannot do opposite things at the same time. However, they recall stories of people who are thirsty but refuse to drink, and who pass by some corpses at which they want to look, but refuse to look. Socrates then summarizes by saying that "a person's desires force him to something to reason, and he berates himself and gets indignant with the part that forces him, and his spirit allies with reason as though reason and desire were at civil war." Book 4, pg. 107, line 440 However, they also show that the spirited part of the soul often is in harmony with the part exhibiting reason. Thus, there appear to be three parts to the soul (since they are not always in harmony): the rational part, the part of desire, and the spirit.
Just like the city, it is only fitting for the rational part to rule, because it is wise and has forethought for the whole soul. Accordingly, the spirited part will obey and be its ally. With this in mind, and with the education and physical training that a person will experience throughout their life, it can only be assumed that the rational and spirited parts will learn to control the desiring part, and ensure that the body minds its own business and thus remains just.
From here, it can be seen that people are brave when the "spirited part preserves through both pleasures and pains the commands of reason about what is and is not to be feared." Book 4, pg. 110, line 442c Also, people are wise because of that part in them which rules for the advantage of itself and the other three parts. People are temperate because of the love and harmony between these three. Thus, it can be established that "justice, although it resembles a mirage, is really concerned with internal rather than external activity - with the true self and its business." Book 4, pg. 111, line 443c Accordingly, a just person will first ensure that he is just, and that all his internal affairs are in accordance with justice, prior to engaging in external affairs.
To elaborate, Socrates and his companions state that justice is "establishing the parts of the soul so that they dominate and are dominated by each other according to nature, injustice so that they rule and are ruled contrary to nature." Book 4, pg. 112, line 444d
Therefore, excellence must be the health and well being of the soul. Socrates continues, stating that it seems to him that excelle