 For Mulla Sadra, the mind possesses an ontological realm that one calls mental existence, a concept that is equivalent to existence-knowledge (Rahman 1975: 215-20). He is a realist in the sense that every thought must correspond to a real object even if it is a Meinong object, that is, an unreal object of cognition. By positing a realm of mental reality, he is a dualist. But the existence of the mind and mental existence are not the same since the existence of the mind is itself an extra-mental reality, while mental existence is what refers to extra-mental existence. This is a subtle but significant distinction. He clarifies this in response to an objection that the existence of a thing cannot be analytically dissolved into the mental and extra-mental (i.e. concrete) being of a thing. Consequently, for Mulla Sadra, the ‘hard problem’ of mind-body does not occur since the existence of the mind is extra-mental existence. There are two primary modes of existence each distinct and radically non-interchangeable: being in re and mental existence.