d the three aspects of the soul can also be seen as three parts of the psychology of the mind--the reason, the emotions, and desire. The three operate in every mind and vie for supremacy at different times. The three parts will be developed in different ways in different characters. Plato begins by examining the way motives come into conflict within the individual and concludes that because of this, we cannot logically assume that there are less than three parts to the soul because there are three types of motives. Reason is the first of these, and it is identified as the faculty that calculates and makes decisions. Desire or appetite is the second, and this is a reference to physical and instinctual craving. The third is emotion and includes all of the emotions which are identified with unthinking impulse.
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