  In contrast with creatures, which are mid-level on the scale of being because they are open to existence and non-existence, the notions of complete nothingness (omnino nihil) and completely pure being (esse purissimum) have absolutely opposed implications for existence. “Complete nothing-ness” is logically inconsistent with real existence, so there is a perfectly valid inference from the notion of nothing to non-being (non-esse). Nothing cannot exist. If the nature of nothing entails its non-existence, the nature of its opposite, completely pure being, entails its real existence. Making use of the categories of his own metaphysics in this way shows more effectively than merely backing the mind into a contradiction why the ontological inference is valid.