Plato’s Republic Book IV: Justice and the Soul

In this “book”(chapter), Plato looks back on thee ideal state previously described and looks at how its outline or whole exhibits justice. How can a group be happy as opposed to individuals? He then discusses how extreme wealth and poverty are the main causes of the “degeneration” of states and class wars. To avoid this he believes that a proper system of education is the only means, if this is kept up the the people will do their business needing very few laws. This education is made up of athletics and “music” which includes many humanistic fields of study from poetry to history and astronomy. He has a lot to say about our what we call “music”, as well as severe criticism of doctors who over-medicate their wealthy patients.
But the best part of the chapter focuses on the nature of the healthy soul, using the ideal state as a metaphor for the soul and the individual soul as a metaphor for the state.