 Mental existence shares the same qualities, features and description as extra-mental existence because it is merely another mode of existence, a certain sense of the term. Just as extra-mental existence is not ambiguous, neither is mental existence. It is homonymous and modulated. Similarly mental existence is not a universal; we have seen above the argument denying that the concept of existence is a universal. The distinction between mental and extra-mental is rooted in the Platonic distinction between sensible and intelligible being, and in the Avicennan distinction between existence and essence in contingents. It is precisely because of mental existence that humans can conceive of entities that do not have any reference in extra-mental reality. 