The Paris Condemnation of 1277, Potenita Dei Absoluta, and the Birth of Modern Science

Abstract

Still present in the historiography of medieval and early modern science is the thesis, originally formulated by P. Duhem and advocated today by E. Grant in a more moderate form, according to which the Paris condemnation of 219 propositions in1277 entails an affirmation of potentia dei absoluta, which led to a criticism of Aristotelism and, consequently, to the birth of modern science. The author argues that this thesis can not stand the test of critical examination. The discussion about “the dialectics of God's powers” (potentia dei absoluta – potentia dei ordinata) began a good half century before the condemnation, which, on the other hand, does not represent the decisive factor in promoting this distinction. By comparing the discussion on the plurality of worlds before and after the condemnation, it can be shown that Aristotle's understanding of the unity of our world was, from the theological perspective (what God might have done), in fact brought into question before the condemnation, but that before and after the condemnation nobody believed that there in fact exists more than one world. “The critique” of Aristotle is epistemologically limited to considerations par esbatement or secundum imaginationem: what God with his potentia dei absoluta might have done. On the basis of Galileo's reflection on the epistemological status of the concept of potentia dei absoluta, the difference between medieval and modern, i.e. Galilean, science can be shown. According to Galileo, the task of science is not to explore what God might have done, but what God actually did.