, Volume 43, Issue 2, pp 475–483 | Cite as

On the PROVER9 Ontological Argument

  • T. ParentEmail author


Oppenheimer & Zalta have re-formulated their non-modal version of the ontological argument, with the help of PROVER9, an automated reasoning engine. The authors end up rejecting the new argument; however, the theist has a rejoinder worth considering. But after presenting the rejoinder, I highlight that the conceivability of the being does not imply its possibility. One lesson is that even non-modal ontological arguments must engage modal matters concerning God. Another lesson is that if PROVER9 is able to derive a conclusion from fewer premises, the proof is sometimes inferior as an argument.


Atheism-theism debate The ontological argument for God's existence Being Modality Impossibilia or impossible objects 



My thanks to Ed Zalta and an anonymous referee for comments and discussion on this material.


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Copyright information

© Springer Science+Business Media Dordrecht 2015

Authors and Affiliations

  1. 1.Department of Philosophy (0126)Virginia TechBlacksburgUSA

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