Aquinas’s Real Distinction and Its Role in a Causal Proof of God’s Existence

Keywords: Aquinas’s argument, Kerr’s reconstruction, criticisms of Aquinas’s argument, Kenny’s critique of Aquinas, Buridan’s critique


This paper is not going to offer any criticism of the way Gaven Kerr treats Aquinas’ argument. Instead, it offers an alternative way of reconstructing Aquinas’ argument, intending to strengthen especially those controversial aspects of it that Kerr’s reconstruction left untreated or in relative obscurity. Accordingly, although the paper’s treatment will have to have some overlaps with Kerr’s (such as the critique of Kenny’s critique of Aquinas), it will deal with issues essential to adequate replies to certain competent criticisms of his argument untreated by Kerr (such as Buridan’s critique). For the sake of the “formally inclined” reader, the paper’s treatment will also include an Appendix offering a formal reconstruction of both the main argument and its sub-arguments to demonstrate the formal rigor of Aquinas’ original.

Author Biography

Gyula Klima, Fordham University, New York

Gyula Klima, PhD — Professor of Philosophy at Fordham University, New York, NY, USA


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Kenny, Anthony. Aquinas on Being. Oxford: Oxford University Press, 2002.

Klima, Gyula. “Aquinas vs. Buridan on Essence and Existence, and the Commensurability of Paradigms.” In Metaphysics: Aristotelian, Scholastic, Analytic, edited by Lukáš Novák, Daniel D. Novotný, Prokop Sousedík, and David Svoboda, 169–184. Heusenstamm: Ontos Verlag, 2012.

Klima, Gyula. “On Kenny on Aquinas on Being: A critical review of Aquinas on Being by Anthony Kenny,” feature review in International Philosophical Quarterly 44 (2004): 567–580.

Klima, Gyula. “Whatever Happened to Efficient Causes?” In Skepticism, Causality and Skepticism about Causality, edited by Gyula Klima and Alexander W. Hall, 31–42. Proceedings of the Society for Medieval Logic and Metaphysics, Vol. 10. Cambridge: Cambridge Scholars Publishers, 2013.

Medieval Philosophy: Essential Readings with Commentary, edited by Gyula Klima. Blackwell Publishers, 2007.

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