10.4225/03/56300691CDE7F Graham Oppy Graham Oppy Pruss' Ontological Arguments Monash University 2015 Alex Pruss ontological argument higher-order ontological argument Godel's ontological argument Godel Anselm Gaunilo Philosophy 2015-10-27 23:19:44 Journal contribution https://bridges.monash.edu/articles/journal_contribution/Pruss_Ontological_Arguments/2004480 Final Published Version: Religious Studies 45, 2009, 355-63