1) the term 'ontological' comes from the Greek 'ontos', meaning 'essence', 'existence', 'being'. The OA is based on the claim that God's existence can be deduced from his definition-that once God is correctly defined, there can be no doubt that he exists2) The Ontological Argument claims that: - the proposition 'God exists' is a priori/deductive - it can be known to be true without reference to sense experience, just by thinking about God's nature
- in the proposition 'God exists', the subject 'God' contains the predicate 'exists', so God must exist
- God's existence is a necessary truth, not a contingent one