Alex O'Connor on The ontological argument
O'Connor regards the ontological argument as a fascinating philosophical puzzle but not a sound proof of God's existence.
O'Connor treats the ontological argument with more philosophical respect than most popular atheists, engaging seriously with both Anselm's original formulation and Plantinga's modal version. He finds the argument genuinely interesting as a piece of philosophical reasoning — but ultimately unpersuasive, because it attempts to derive a substantive existential claim from the analysis of a concept.
His primary objection follows Kant: existence is not a property that can be included in the definition of a thing. To say that God exists does not add anything to the concept of God — it asserts that the concept is instantiated. The ontological argument conflates conceptual analysis with existential proof, and no amount of logical refinement can bridge that gap.
On Plantinga's modal version — which argues that if it is possible that a maximally great being exists, then it necessarily exists — O'Connor notes that the key premise (that a maximally great being is possible) is precisely what is in dispute. The argument is logically valid but begs the question: if you grant the possibility of a necessary being, you have already conceded its existence. The argument proves nothing to anyone who does not already accept its most controversial premise.
“The ontological argument is a beautiful piece of reasoning. But you cannot think things into existence, no matter how cleverly you define them.”