Abstract
This paper reconstructs the account of concept formation developed by Themistius in his commentary on Posterior Analytics. Unlike modern day psychological empiricists, Themistius ascribes an active role in concept formation to our innate capacity of understanding.
Unlike intuitionists, he would not be satisfied by saying that νοῦς "intuits" or "spots" concepts; rather, the question is what makes our νοῦς capable of "finding" and "recognizing" concepts in experience and this can only be an understanding prior to all experience. I suggest that Themistius was pushed in this direction by Platonist arguments against Aristotle's epistemology: postulating a "potential νοῦς" is not enough, for one can apply Meno's dilemma to it - how can it recognize that what it finds is what it looked for? But, contrary to the judgment of some modern scholars, Themistius never embraced the theory of recollection either.
Despite his originality, he sees himself as offering a genuinely Aristotelian account.