Throughout history, the desire to attain it has led men to war, women to murder and humanity to the brink of self-destruction. Master and pupil, Plato and Aristotle, through their respective works, "The Republic" and "Nicomachean Ethics," have each written extensively on the topic of happiness and fulfillment. Plato wrote through dialogue and Aristotle through a more straightforward essay, they both explored the importance of happiness and the ways to reach it. Both men argue for happiness as an end as well as virtue as a vital means to this end, however, they differ on virtue and therefore differ on happiness. While Plato makes a strong argument for knowledge as the sole factor needed to reach virtue and happiness, and although Aristotle discusses the necessity of knowledge as well, Aristotle's rebuttals against Plato's definition of happiness prove to give a more realistic and practical answer to this long fought over question.
The difference between the two philosophers stems not from the virtues themselves but how one acquires these virtues. To put it simply, Socrates holds the belief that knowledge is virtue, as in knowing what is good is to do good. In describing the philosopher king, the perfect leader and most virtuous person, he says that they are, "always in love with that learning which discloses to them something of the being that is always and does not wander about, driven by generation and decay (Plato, 485B). " What can be drawn from this is that the keeper of virtues is a lover of wisdom and furthermore, virtues stem from wisdom. His argument simplified is that if one has wisdom and knowledge, he is virtuous, and if he is virtuous, he is happy. This also shows .
Plato's belief in the unity of the virtues. This is seen throughout The Republic especially when speaking of the soul. He gives three parts to the soul: calculating, spirited, and desiring. These three correlate to the three virtues of wisdom, courage, and moderation.