A superação da dicotomia céu-terra: um estudo da crítica galileana à física e à cosmologia aristotélicas

Abstract

In this thesis, we aim to conduct a study and reconstruction of the criticism that Galileo undertakes to physics and cosmology of Aristotle, and works as an anchor Sidereus Nuncius and First Day of Dialogue Concerning the Two Chief World Systems. The arguments developed by Italian physicist these works, consolidating the Copernican theory and revolutionize the way we study nature. For centuries, the Western conception of the universe was supported by the assumptions of cosmology of Aristotle. Aristotelian cosmology had as fundamental points the idea of the incorruptibility of the heavens, the earth and the immobility of a hierarchy of elements. For the peripatetic, the cosmos was finite and heterogeneous, and was divided into two distinct regions: the sublunary (terrestrial) and above the Moon (heavenly). The telescopic observations made by Galileo in 1609, showing craters and mountains on the moon and Jupiter's satellites, were in evidence against the heaven-earth dichotomy proposed by Aristotle. For it revealed "imperfections" in the heavenly bodies, and showed that not all the stars had their revolutions as the center of the Earth, the idea of asking the same centrality in the cosmos. Moreover, the break with Aristotelian cosmology destabilizing the very physics of Aristotle, whose explanation of the movements of bodies depended on the cosmological structure, since there were three types of moves, straight toward the center, straight away from the center and circular around the center, which required a motionless earth occupying the center of the cosmos. The idea of centrality and immobility of the Earth is therefore fundamental point of Aristotelian physics and cosmology. Most of the work of Galileo Galilei seems to think about a central objective: the defense of the Copernican theory. Since his public adhesion to the Copernicanism in 1610, in Sidereus Nuncius, until Dialogue published in 1632, the Pisan Phisycist sought to break with the assumptions of the Aristotle s natural philosophy which supported the geocentric conception. As a result, it is in First Day of Dialogue that, certainly, we could find a more systematic and focused effort against the Aristotelic conception of world and its main characteristic: the dissociation of the cosmos into two distinct regions, the celestial and sublunary.