Induzione ed enumerazione in Descartes : metodo dimostrativo e scoperta scientifica

Despite much classical historiography has seen Descartes' philosophy as a rigorously deductive «order of reasons», inductive and enumerative procedures play an important role in Cartesian method. Descartes takes these operations to be the cornerstones of his analytical method, since he states explicitly that «enumeration is requiredfor the completion of science». Accordingly, this article aims at providing a terminological and conceptual introduction to Descartes' theory of induction, considering the different contexts (epistemological/physical) in which it is applied. Descartes defines it as a close and accurate examination of all that pertains to the question proposed, such that we can conclude certainly and evidently that we have not forgotten anything. As such, induction can be compared to enumeration («enumeratio sive inductio» in the Regulæ), with which it is sometimes identified. A classical enumeration is also the way in which Descartes explains the nature of light by comparison («mitatio») to other «natural powers», which fall under the same idea of extension. Induction gives «some idea» of the properties of light in the Dioptrics (1637) by comparison («comparatio») with other similar phenomena. By addressing the question of knowledge in terms of «chains of deduction» and «sufficient enumeration», both Descartes' early career and his later philosophical system suggest a new account of logic as a "logic of discovery". Descartes believed the formal logic of his day (the logic of syllogisms) only to be of use in explaining things to others, not in making new discoveries, whereas Baconian induction was unable to undertake properly scientific and natural philosophical endeavors on account of its unmethodical character. Nonetheless, Descartes' account of analytical and inductive reasoning is deeply embedded in the contemporaneous debate on the hypothetico-deductive method. It is my goal to show how the synthesis between reason and experience offered by Descartes' inductive-deductive procedure represents the focal point for subsequent scientific and philosophical debate, as well as one of the most important sources in the development of modern science.