Descartes’ Proof of God: A Critical Analysis
Descartes’ Second Proof of God’s Existence
Summary
Descartes argues that his idea of a perfect God cannot originate from his imperfect self. The idea of perfection, which he lacks, must come from a perfect being, namely God. Therefore, God must exist.
Critique of the Divine Essence
Descartes’ deduction of God’s goodness and truth from his omniperfection doesn’t offer certainty about God’s essence. Knowing God’s essence by analogy, as scholastics did, relies on an illegitimate use of causality. The existence of an imperfect “cogito” created by a perfect God raises questions about free will. We cannot know God’s nature by extrapolating our moral values. God’s goodness is a metaphysical proposition, not refutable by experience.
Comparison with Hume
Descartes believes we can understand God’s nature by analogy. His first two proofs assume that every effect has a cause with at least equal perfection. Hume, however, critiques the principle of causality. He argues that causality requires constant conjunction of cause and effect, but we don’t experience the necessary connection between them. Our certainty about causality is psychological, based on habit. Hume believes causal inference is valid only between impressions. Descartes’ inference of God’s existence is unjustified because it moves from an impression to something beyond experience. Hume argues against using causality to infer extra-mental realities or divinity from mental contents.
Personal Opinion
While every effect has a cause, the reverse isn’t necessarily true. Attributing extra-mental reality or divinity to mental contents is an illegitimate use of causality. Our belief in causality is psychological. We can argue logically, but experience cannot guarantee future observations. Metaphysical propositions, while unverifiable, are not meaningless and play a role in scientific theory development. Our belief in regularities leads us to search for universal laws and explanatory models.