John Duns Scotus · Theology
Scotus’s positive principle of individuation - <em>haecceitas</em>, ‘thisness’ - the ultimate reality that makes this individual <em>this</em> unrepeatable thing, over and above the common nature (natura communis) it shares with everything else of its kind.
Look at any individual - Socrates, this oak, that grain of sand. Each has a nature it shares with others of its kind: Socrates is human, and humanity is something Plato and you and countless others possess too. But each is also, irreducibly, this one: a single, unrepeatable individual, not merely an instance of a type. So here is the puzzle that obsessed the medievals, the problem of individuation: given the common nature that many things share, what is it that makes an individual this individual and no other? What seals off Socrates as one, unique, indivisible thing? The favourite answers of the tradition pointed to matter, or to quantity (this parcel of stuff, here, now). Scotus examined them all and found them wanting - and in their place proposed one of the most original ideas in all of metaphysics.
To see why haecceity is needed, start with what it acts upon: the common nature (natura communis). Scotus, following a famous idea of Avicenna, held that a nature such as humanity or horseness, considered in itself, is indifferent to being one or many. Of itself, the nature is neither universal (as it becomes in the mind, thought of as one over many) nor individual (as it becomes in reality, in this or that thing); ‘horseness,’ as Avicenna put it, is just horseness. The nature is genuinely real in things and has its own ‘less-than-numerical’ unity - it is really common, not a mere name - but it is not yet this. It is, so to speak, metaphysically unfinished, waiting to be sealed as an individual. Something must come to the indifferent nature and make it this horse, this human. That something is the haecceity: the final actuality that turns a shareable nature into an unrepeatable individual.
So what is the haecceity? Scotus is careful: it is not a further quality the thing has (Socrates is not individuated by his snub nose or his wisdom, for those could in principle be shared). It is not a component you could point to. It is, rather, the ultimate reality of this being - the last, individuating actuality that makes the whole nature-in-this-thing be this and incommunicably one. Haecceity is indivisible (you cannot split it into parts) and incommunicable (it cannot be shared by, or predicated of, more than one). It is what is left over when you have specified everything about a thing’s nature and properties and still have not said which individual it is. Two perfect twins, alike in every quality, would still differ by their haecceities. It is thisness itself: the metaphysical seal of the singular.
This is the opening of the lesson. The rest — the dialogue, the primary source, and the recall — is in the app.
You learned that Scotus rejected matter and quantity as the principle of individuation and posited haecceitas (thisness), a positive formal reality that contracts the common nature (natura communis) down to this single individual. Explain the common nature, the haecceity, and why individuality needed a positive cause…
Leads to Aristotle.
Begin this lesson →epoché — a humanities education that remembers you.