The moral philosophy we know and recognize today in the Western world is slave morality, a morality that proposes ideals of fairness, equality and democracy. However, many centuries ago, during the Middle Ages, master morality was the norm; a morality that favors those superior in strength, beauty, intelligence, and status. The morality of the master preceded the morality of the slave. Friedrich Nietzsche was a philologist, who used his knowledge of words to trace the origins of morality from their ancient definitions. He said that morality was something that man, especially the nobles, had created because they were in a position that allowed them to declare what should be considered good or bad. The concept of “good” arose when aristocrats examined themselves and saw that they were rich, beautiful, healthy, strong, and powerful. Then they looked at the slaves below and saw how poor, vulgar, ugly, dirty and weak they were; which led them to the conclusion that slaves must be “bad” because they were the opposite of the nobles who were “good.” The pathos of nobility and distance, as already said, the fundamental, prolonged and overbearing total feeling of a higher dominant order towards a lower order, of a “below” – this is the origin of the antithesis of “good” and “bad” (Genealogy of Morals, page 26). Their superiority, which began in a social sense, underwent a conceptual transformation in a moral sense which gave the definition of having a “high-level soul”, “with a privileged soul”. The slaves became angry and enraged at being labeled “evil,” so they devised a plan to turn their miserable situation into something beneficial. Because they were not strong and powerful enough to defeat their lord... middle of paper ......ol and all this leads him to reach reason and conscience. Human understanding owes much to passions. It is through the activity of the passions that our reason improves. Passions owe their origin to our needs and their development to our knowledge, since one can desire or fear something only if one has an idea of ​​it in one's mind (Discourse on Inequality, p. 89). Reason is what teaches us to know "good" and "evil". The search for the origin of morality has a long genealogy from Jean Jacques Rousseau who researches the evolution of man with his needs, passions, desires and Friedrich Nietzsche who traces the etymology of "good" and "evil" discovering their meanings original. Individualism and inequality push human beings to start from the comparison on which morality is based. The different perspectives on morality are supported by psychological and biological nature.