According to Socrates, good is defined as an absence of bad, just as bad is an absence of good. Plato doesn’t directly come out and say what The Form of the Good is, but through his examples and implications, we find out that it brings all other forms into existence. He compares it to the role of the sun in the playing out of the sun and earth. Some people described The Form of the Good as God, but Plato doesn’t actually imply that anywhere. The four main virtues: wisdom, courage, moderation, and justice. The first one, wisdom, is the presence of knowledge and understanding. It also can be described as, knowing what to do with what you know. It lies within the guardians, as they have knowledge of how to run a just city. “Then what gives the objects of knowledge their truth and the mind the power of knowing is the Form of the Good [Book VII].” This is described by the Allegory of the cave. Basically, what he is saying is that good brings knowledge, which goes along with the fact that The Form of Good brings other forms into existence.
The second virtue is courage. Courage is a virtue of passion, and is controlled by through pains and fears, pleasures and desires. This virtue lies within the Guardians, who have to fight for the city. This is found in Book IV. Since a person can be courageous and have either god or bad intentions, it is hard to pinpoint it.
Moderation and justice both lie with in the craftsmen of the city, although, technically, it is spread throughout the whole city.
Moderation is a virtue of self-control. It is also safe to say that it also means the stronger part ruling the weaker part, as a person with any sense of self-control is ruled by the superego keeping the id in line; this being the stronger ruling the weaker. Moderation, in relation to a just city, is the guardians ruling the craftsmen, and everyone being in agreement.
Justice, in the book is described as doing one’s own work,...