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Although Aristotle never explicitly says so, there are compelling textual and philosophical reasons to believe that Aristotle considered truth a pros hen analogous notion. It is an analogous notion, because 1) there is a core instance of truth from which many other types of truth are derived in various ways; and 2) the derived instances are defined or explained in relation to the core instance. At its core, truth for Aristotle is the identity between an intellect and its immaterial object. From that identity Aristotle derives the formal identity that exists both between the understanding and its objects and sensation and its objects. Also derived from the core identity is linguistic truth that is defined primarily by the unity between subject and predicate.

However, to understand the identity at the core of truth, one must realize that for Aristotle, the primary sense of identity is not self-identity, as it is in modern logic. Rather, identity is primarily alio-relative and so to treat oneself as self-identical is to treat oneself as an other. Additionally, Aristotle recognizes several other types of “identity” (t’auta): 1) An accident can be said to be identical with its subject: “Socrates and Socrates is educated are the same;” 2) A subject and its per se predicate can be said to be identical; 3) Things that are of the same substance are in some sense identical. 4) Matter and its form can be said to be identical, e.g. “This wood is a house,” or “This brick is Monticello.”

In the case of truth, the derived instances are each derived from the primary identity between the intellect and its object. In the highest intellect, that of the Unmoved Mover, there is a fully actualized identity between the Intellect and its object, which then is the cause of the identity between potential intellects and their immaterial objects, objects such as essences and mathematical objects. The truths of the understanding then depend upon the insights of the intellect, because the intellect provides the first principles for the proofs that constitute scientific understanding. Sense perception is also true, but to a lesser degree than the truth of the intellect, because the truth of sense perception results from the formal identity between the act of sensation and the actuality of the object of sensation. But the object and sensation differ in their being, so they lack the full identity of the Intellect. Finally, the truth of linguistic predication derives from the types of truth found in the intellect, understanding, and sensation, because linguistic terms are signs of thoughts in the soul.

The types of linguistic predication also stand in a pros hen analogous relation, with per se predication showing the highest degree of unity, but even accidental predications have a degree of unity, as the “log” and the “white thing” both refer to the same object. Even true negations are analogously related to positive predications, because as Aristotle says, non-being is analogous to being.

So, although there are many types of truth in Aristotle, they are all analogously derived from the full identity found between the intellect and its object in the self-contemplation of the Unmoved Mover.