Plato's Republic: Book V Synopsis

Before continuing on to discover the four other virtues of the just city (and soul), Glaucon and Adeimantus demand Socrates explain his idea of the guardians sharing their wives and children. Socrates begins to discuss the guardian lifestyle at length.

The first is that women will be trained and raised in the same way as the men, thus taking on the same political roles. Socrates acknowledges the differences that men and women have in their nature, but posits that both have a demand in their souls. Some will be appetitive, some spirited, and some will be rational. Society will make use them accordingly. 

Socrates then discusses the requirement that women and children be shared among the guardians. The guardians are only permitted to have sex during annual mating festivals. Some guardians will only be permitted to have one couple, while the more admirable ones can have multiple couplings. The children that are born from this festival will be taken and raised together. If there are any children born outside of this yearly festival, they will be killed. 

The idea that Socrates has for this is a more unified city. In most cities, an individual's care is divided between care for their city and their family. In the kallipolis, everyone is considered family. Thus, there are no divided loyalties. Everyone says "mine" about the same things and carries forward with the same goals and concerns. 

The next question Socrates must answer is if this lifestyle and city is possible outside of theory. Before answering this question, Socrates explores the guardians lifestyle relating to war. Children training to become guardians should be taken to the frontlines to see firsthand how war is conducted. They are to be put on the backs of the fastest horses to escape any harm. Any child that is considered cowardly in the face of war will lose their status as a guardian.

Socrates finally arrives at discussion of this city and lifestyle being possible. The only way it can become a reality, in Socrates' eyes, is if philosophers rule the city. This idea has come to be known as the "philosopher-king". Naturally, Socrates first has to define what he envisions for the philosopher-kings. He takes care to distinguish them from the "lovers of sights and sounds" that pervade Athenian society, ushering in the first discussion of the Theory of Forms. 

The Forms are eternal, unchanging, universal absolute ideas. Some examples are the Good, the Beautiful, and the Equal. The Forms cannot be seen, but only understood with the mind. They are responsible for making the things we see around us into the things they are. Anything we see that is red participates in the Form of Red, anything beautiful participates in the Form of Beauty, and so on. The true philosophers have knowledge of these Forms. The "lovers of sights and sounds" claim to know beautiful things but have no knowledge of the Form of Beauty. Thus, they can only have opinions of Beauty but no knowledge of it. 

To demonstrate philosophers only have knowledge, Socrates divides all of existence into three classes: what is, what is not, and what both is and is not. What is, is knowable; what is not is the object of ignorance; and what both is and is not is the object of opinion or belief. The only things completely are the Forms. Only the Form of the Beautiful is completely beautiful, and so on. Beautiful things witnessed in the world both are and are not. A beautiful person can also be not beautiful, depending on the standards applied. Therefore, we can only know the Forms, not their representations in the real world. 

Plato's Republic: Book IV Synopsis

Book IV of Republic opens with Adeimantus questioning Socrates about how happy the guardians could be in their position of society. There are a lot of freedoms that they miss out on, like owning private property, taking vacations, and other practices that most people consider enriching. 

Socrates responds by telling Adeimantus that the goal of his ideal hierarchy is to not allow one class to feel happier than the other, but to promote the overall happiness of everyone in the city. To present anyone with a sort of happiness that takes them away from themselves and their specialty is unjust.

Socrates discusses various other topics related to the guardians' lifestyle. He proclaims that there will be no money in the city so as to prevent wealth and poverty. Adeimantus points out that a city without money would not be able to defend itself in war. Socrates reminds Adeimantus that the city would have the best warriors and that neighboring cities would rally to defend them if the spoils of war were left to them. 

Socrates also imposes a limit on the size of the city, warning that a city that is to large would not be governed well. Guardians should also defend their education above all else and share all of their possessions, including wives and children. Additionally, the city would not need laws as it is as just as can be. Should any points of policy arise, the guardians are well-versed enough in what justice is to decide on them. 

From here, Socrates deems the city complete. The only thing left to do is to be sure the city has the four sought-after virtues, those being wisdom, courage, moderation, and justice. Wisdom is found first, within the guardians because of their knowledge of running the city. The auxiliaries provide the courage as the warrior class. Moderation and justice are found in many parts of the city. Moderation is found in agreement of who should rule the city, and justice is found in every citizen doing the job they are specialized in. Now that justice has been found in the city, justice must now be found in the individual. 

Similar to the discovery of civic justice, individual justice depends on the harmony between its parts. These parts consist of three aspects of the soul, in a concept that has been called the "tripartite soul". The three aspects are reason, spirit, and appetite. The rational part requires truth, the spirit part requires honor, and the appetitive part requires all other physical necessities (food, water, sex, etc.). These three aspects correspond to the three classes in the city. The reason corresponds with the rulers, the spirit is in the auxiliaries, and the appetite is in the producing class. 

Balanced relations are necessary among these parts both in the individual and in the city. In a just person, the rational part rules over the spirit and appetite. However, any soul can be primarily one aspect. A soul sated by truth and ruled by reason are likely to be rulers, and so on. 

At this point, Socrates has achieved his goal of identifying justice in the city and the individual. In this time, Socrates has departed from our conventional understandings of justice as a set of actions. Rather, it is the consequence of a well-controlled soul. The just person seeks truth and wisdom rather than lust, greed, or honor. Finally, Socrates asserts that justice amounts to the health of the soul. An unhealthy soul is an unjust soul. This also answers the question of whether or not justice is desirable in and of itself.