We draw out the line of argument in Avicenna according to which being in act (wujūd bi-l-fi‘l) is not in the definitional content of the ten categories. With the help of al-Ghazālī’s Metaphysica, Aquinas in his earliest writings turns this line into what has been misnamed the “Genus Argument” for the real distinction between essence and existence (esse in actu). Aquinas, as we show, draws on the Avicennian “Categories Argument” in his treatment of the possibility of substance-less accidents unde…
Read moreWe draw out the line of argument in Avicenna according to which being in act (wujūd bi-l-fi‘l) is not in the definitional content of the ten categories. With the help of al-Ghazālī’s Metaphysica, Aquinas in his earliest writings turns this line into what has been misnamed the “Genus Argument” for the real distinction between essence and existence (esse in actu). Aquinas, as we show, draws on the Avicennian “Categories Argument” in his treatment of the possibility of substance-less accidents under divine miraculous power, a possibility required by the received analysis of the Christian mysteries. The theologians’ account of substance-less accidents met with opposition from arts masters at the Universities of Oxford and Paris, and the issue became central in the faith-reason conflict in 1277. Nevertheless, as we detail, these arts masters, together with Dietrich of Freiburg, show little or no knowledge of Avicenna’s teaching or Aquinas’ appropriation of it. In fact, the Avicennian background to Aquinas’ arguments for the essence-esse real distinction has been hitherto largely overlooked in the scholarly literature.
