external reality. Rather, in external reality there are two existent entities, each determinate and distinct from the other. Neither is identical to the other, nor is the very existence of one the very existence of the other. Instead, the mind abstracts an absolute existence common to both. Thus, whoever asserts the oneness of existence is merely asserting the oneness of this absolute, mental existence.

Someone who holds that existence is additional to essence may say that the existence of different essences belongs to a single genus. Although this view is unsound, he does not say that the very existence of one entity is identical to the very existence of another, for this contradicts sensory perception and clear reason. This is why al-Tilimsānī, the leading figure among these proponents of union in his time, says: