In Schilderboeh by Carel van Mander, Pieter Bruegel was regarded as a painter come of peasant class because he could paint peasant life vividly. But the studies by Max Dvorak, Charles de Tolnay and Otto Benesch in the 19th century came to insist that Pieter Bruegel was rather a philosopher in the same current of thought as that of liberarists at his time than a painter simply for peasants. In this article the writer attempts to trace the development of his philosophy by landscape drawings during his life time, which were collected in the complete catalogue-Tolnay; The Drawings of Pieter Brugel the Elder 1952. In Northern artists, his originality can be found in his intention to express the universal conception in drawing against the influence from Italian Renaissance in Flanders at those days. In this point, he has something in common with the thoughts in "Paradox" by Sebastian Franck who contemplated the universal necessity behind this world. Thus, it will be safe to say that Bruegel was the first painter who expressed new universal conception, escaping from Medieval thought, under which Jan van Eyck and Hieronymus Bosch lived in the same native land as Bruegel.