Beginning with an overview of Galileo's earliest work on free fall, the paper examines the relationship between experiment and theory in his study of motion in the period immediately before and after 1604. The possible role of experiment is assessed in relation to the manuscript evidence and by means of reconstructed experiments.

Les veloppement de la philosophie d'Averrotre mieux dvisions qu'Averrome de ses ouvrages que par l'ordre traditionnel de ses commentaires ; ces res par Averrotapes initiales sont infiuenctations d'Alexandre d'Aphrodise et par Thtapes finales de son loigne de ces auteurs et se rapproche de la pense par la lecture par Averrobut du Livre VIII de la Physique: ls est d'accord avec Aristote dans la premitape de son parcours et s're, puisqu'il croit par la suite que le dessein d'Aristote dans cette partie (...) du livre ternitleste. En ce qui concerne la lecture diffcution qu'Averroes et d'autres philosophes subirent en 1197. II n'affirme plus que la philosophie est la voie pour parvenir à la perfection humaine mais veut settlement exposer clairement la philosophie d'Aristote. (shrink)

ArgumentThis paper discusses the theory of motion of the philosopher Honoré Fabri (1608–1688), a senior representative of early modern Jesuit scientists. It argues that the consensus prevailing among historians – according to which Fabri's theory of impetus is diametrically opposed to Galileo's or Descartes' concept of inertia – is false. It shows: that Fabri carefully constructed his concept of impetus in order to easily incorporate the principle of linear conservation of motion (designated here as “limited inertia”), by adopting formal (rather (...) than efficient) causality between impetus and motion and by allowing impetus to act only along straight lines; that he explicitly deemed Aristotle's famous “inertial paradox” not as a paradox at all; and that linear conservation of motion was not limited to “counterfactual” circumstances but played a significant part in his discrete theory of free fall and constituted an integral component of his general physical (and even mathematical) philosophy. However, the paper also shows that Fabri's notion of inertia was restricted to one dimension only, and therefore should indeed be considered “limited.” In his analysis of horizontal projectiles, Fabri explicitly rejected Galileo's important principle of superposition, and thus revealed significant constraints to his “inertial” thinking. (shrink)

Can one deny the intelligibility of “extramental nonbeing” in pure ontology while affirming its intelligibility in physics? When one sweeps the heavens clean of matter does one also necessarily affirm the existence of absolute nonbeing in those “clean” spaces? Does talking about space necessarily mean talking about nonbeing? How could there possibly be “space” which is not absolute nothingness? How, if at all, can statements about space be reconciled with such self-contradictory statements as “What is not, is“?The purpose of this (...) brief paper is not to argue, within the context of the physical sciences, about whether or not there exist voids or absolutely empty spaces in the universe. Neither is it to discuss the existence or nonexistence of the aether. And although I shall be using texts taken from several famous historical figures, my purpose is not primarily historical. (shrink)