Regarding the particular issues of natural philosophy, Oresme appears to be at the same time a product of the Aristotelian tradition and a scholar looking for novel and accurate descriptions of natural phenomena. An example of this twofoldness is his theory of time in which his setting is clearly contemporary and yet his conclusions go beyond Aristotle’s views. Oresme argues that there are two meanings for the term ‘‘time.’’ Its proper sense is a successive duration of things; it is neither a substance nor an accident inherent in a subject. Thus time is, in contrast to permanent things, an ever flowing entity, res successiva. The broader meaning of the term ‘‘time’’ is the unit ofmeasure which, in the first place, is used to measure motion in the heavens and the motion of the sun in particular, and which is secondarily applied to local motion. Oresme’s definition of the proper as well as the improper sense of time deviated from Aristotle’s conception which by definition connected time with motion as it is ‘‘the number of movement in respect of the before and after.’’
Where Oresme’s notion of time shows his deviation from traditional views, a great many other examples are prove of his unwillingness to depart from prevailing scientific explanations. An example of this tendency is the question of the diurnal rotation of the earth, which Oresme discussed in Le Livre du ciel et du monde. Here Oresme presented several arguments to prove that astronomical phenomena could be explained by the earth’s rotation contrary to the commonly accepted theory which postulated that the earth was the center of the universe around which the heavens moved. Rational arguments indicated that the rotation of the earth was a plausible, even a better explanation than the alternative theory. Still, Oresme considered experience as insufficient for demonstrating either of the theories and, as usual, chose the traditional explanation: ‘‘However, everyone maintains, and I think myself, that the heavens do move and not the earth: For God hath established the world which shall not be moved, in spite of contrary reasons because they are clearly not conclusive persuasions.’’ The quote expresses the uncertainty of natural knowledge, an attitude which characterizes his last work, Le Livre du ciel et du monde. Oresme, being a theologian, gave preference to articles of faith over natural reason. As a natural philosopher he is also a traditionalist: despite presenting ingenious emendations and radical alternative resolutions, Oresme remained within the broad limits of the Aristotelian framework.
World History
