Since the XIX century, a pleiad of philosophers and historians support the idea that Greek philosophy, usually reported to have started with the presocratics, lays its basis in a previous moment: the Greek myths – systematized by Homer and Hesiod – and the Greek arts, in particular the lyric and tragedy literature. According to this, it is important to retrieve philosophical elements even before the pre-Socratics to understand the genesis of specific concepts in Philosophy of Law. Besides, assuming that the Western’s core values are inherited from Ancient Greece, it is essential to recuperate the basis of our own justice idea, through the Greek myths and tragedy literature. As a case study, this paper aims on the comparison of two key-works, each one representing a phase of the Greek tragedy: The Orestea, by Aeschylus, and Orestes, by Euripides. Both contain the same story, telling how the Greeks understood the necessity of solving their conflicts not by blood revenge, but through a political way, and also the political drama. Although, in Aeschylus’s one, men still leashed by their fate, while the gods play a major role, in order to punish human pride (hybris). In a different way, on Euripides’s work men face their own loneliness, in a world fulfilled with gods, each one demanding divergent actions. That represents a necessary moment to the flourishing freedom and human subjectivity, and, once the exterior divinity is unable to resolve human problems, men will need to discover their interior divinity: that is how the Philosophy emerges.