WEAKNESS : KANT - predicate Existence is not a predicate, not part of a sentence which describes a quality
Descartes assumes that it is when assuming that existence is a perfection and therefore the perfect version of a quality
the word exists doesn't add any more info to our understanding
existence is the precondition of an object, first the object must exist, then other predicates can be attached to it
Ordinary language test - wouldn't describe a pen as existent, not used as an adjective or a quality - you would say a pen is plastic, has black ink, is smooth writing but you wouldn't call it existent
existence isnt a predicate, descartes makes error in language