Emanuele Severino, one of the most important contemporary Italian philosophers, explains Presocratics and the birth of philosophy.The Presocratics were the first thinkers to reject mythological explanations of the world and to explore the rational principles of reality. The works of Thales, Heraclitus and Parmenides paved the way for the thoughts of Plato and Aristotle; their theories gave the birth of the Western philosophy.