I’ve occasionally had the disappointing experience of walking into a bookshop, seeing a shelf marked ‘Metaphysics’ and, beginning to peruse it, only then finding that it’s filled with volumes on mindfulness, crystals, and learning about one’s past lives. I wouldn’t be surprised if New Age enthusiasts have occasionally had the reverse disappointment upon learning that a ‘Metaphysics’ course they signed up for will involve arguing about the nature of reality, personal identity, and the problem of free will.

This confusion over what metaphysics is, exactly, is an old one. A historically-minded person asked to define this field of philosophy might say that metaphysics simply studies the sort of issues tackled in Aristotle’s Metaphysics, the first work to use the word in its title. But this answer would need a significant caveat: Aristotle did not use this title himself, and indeed the book is almost certainly a collection of disparate materials cobbled together centuries after Aristotle’s death.

Because it is a composite work, maybe we should not expect a unifying theme in the Metaphysics. Perhaps it is called by this title just because it is to be read after (meta) Aristotle’s discussion of natural philosophy in his Physics. On the other hand, perhaps the compiler had good reasons for putting these materials together as a single text. Intelligent readers, from the great ancient commentator Alexander of Aphrodisias, to the also pretty great medieval commentators Averroes and Thomas Aquinas, have indeed detected a single project running throughout the Metaphysics, although without agreeing what it was.