The coursebook presents Plato and Aristotle as the two most significant and groundbreaking thinkers of European thought from the era of classical Greek philosophy. The author provides prefatory orientation in the labyrinth of their complex thought and sketches their metaphysics, problems of knowledge and ethics. He departs from the fact that both thinkers are similar in striving to overcome problems of their period by localizing the human being into a hierarchical order of beings, which obliges in questions of the possibility of knowledge as well as of the right conduct.