St Anselm was impressed by Gaunilo’s objections and wrote a careful reply to him. The crux of Anselm’s response was that his argument only applies to the greatest possible being: it is part of the essence of the greatest possible being that it must exist. It is not part of the essence of the greatest possible island that it must exist (islands can exist or not), but it is part of the greatest possible being that it must exist. So whether an atheist thinks Gaunilo’s Lost Island objection is decisive against Anselm’s first argument, will depend on whether they think there is a relevant difference between the greatest possible island and the greatest possible being.
A more recent argument, put forward by Descartes, provides more weight to…show more content… However, the argument clearly has its weaknesses and primarily this is that the argument is successful in proving that if God exists then he must exist, although for the atheist, this may not be enough. Interstingly, even among the faithful there are theories that suggest the idea to know of God’s essence at all is impossible, as the great theologian Aquinas remarked: “we do not know the essence of God”11 Clearly, there can be little doubt that the Ontological Argument has stimulated huge amounts of debate and even in the last century thinkers, philosophers and theologians such as Hick and Malcolm have attempted to rework the argument in a manner of different ways. However, despite this constant reworking, perhaps the argument’s real value is only in the devotional, for those who already believe, and not for the atheist. After all, to truly show that God must exist with this argument, one must accept that God exist to begin with which perhaps explains why Anselm originally set it out not as a formal proof, but as a