Plato's famous theory of the “concept of the soul” is found in his book The Republic. Here, Plato responds to the sophists on why we should live morally. Back when the Sophists were men who used philosophy for profit, they did so by inventing moral loopholes to evade people from their obligations. Or excuse people for their bad actions or immoral behavior. They questioned Plato, asking, “Why should one be moral when morality is apparently a social means of maintaining order.” He responds by saying: Morality is a direct cause of happiness, happiness responds directly to our moral behavior. Therefore, an immoral person would be moral if he wishes to become happy. The already happy person, according to Plato, is the just person. He describes this with a sort of graph. If “X” is happy, then “X” is right and if “X” is right, then “X” is happy. Plato goes further by dividing the human soul into three Meros, or parts: Logos (reason), Thumos (spirit/emotion), and Eros (appetite). Reason is given the greatest value, while emotion and especially appetite are considered the "lower passions." Plato believes that the soul is governed by reason. Therefore, our appetites and emotions must come under the control of reason; in other words, they follow the dictates of reason. Plato believes that the soul should be the state of society, or in his words dikaios (just). He bases his three-part thesis on the human soul on the common experience of confusion and internal conflict that all humans share. He discovered that there are three basic activities in a person. First, be aware of a value or goal. Second, all people are moved toward action that is neutral at first but responds to direction... middle of paper ... the "righteous" person has the virtue of courage. In relation to “Reason”, the happy or just person possesses wisdom (prudence). In relation to appetite, the “righteous” person possesses the virtue of temperance, which in turn controls natural desires. Plato says that the fourth fundamental virtue is justice. Justice comes from outside a person and directly influences people through the act of charity and kindness. Plato's theories seemed to make sense at the time, but they had many notable problems. Plato himself, at the beginning of his dialogue, declares: "It is impossible to arrive scientifically at a conception of the human soul." His view of the human soul is based more on his vision of a perfect society than on logic. Plato says: "The soul must rather be considered as a distinct entity within the human being, directed not by society but by an internal and quintessential vital force within the human being.”.