First of all, it needs to be noted that for Plato the human being is composed of body and soul. And the two are essentially different. This is the essence of Platonic dualism. The soul had existed before coming into the body and also exists after leaving it. (The Republic, Part VI, Book X, "Immortality and the rewards of Justice"). It is also established that the soul is superior to the body and controls it.
In chapter XIII of the Republic, Plato gives the three parts of the soul as corresponding to the three elements of the society, namely deliberative, executive and productive. This is because the ...
Plato's definition of the human being and how the three parts of the soul correspond to the three divisions of society is the subject of this post. How does Plato envisage harmony in the human being and the human society?