According to Aristotelianism, the distinctness of two items of the same species is grounded in the distinctness of their matter. This had better be initial matter, since an item might change all of its matter as it grows.
But now imagine a seed A which grows into a tree. That tree in time produces a new seed B. The following seems possible: the chunk of matter making up A moves around in the tree, and all of it ends up forming B. Thus, A and B are made of the same matter, yet they are distinct. (If one wants them to be at the same time, one can then add a bout of time-travel.)
Probably the best response, short of giving up the distinctness-matter link (which I am happy to give up myself), is to insist that a chunk of matter cannot survive substantial change. Thus, a new seed being a new substance must have new matter. But I worry that we now have circularity. Seed B has different matter from seed A, because seed B is a new substance, which does not allow the matter to survive. But what makes it a new substance is supposed to be the difference in matter.
Plants produce seeds (or fruit which contain seeds). If B is a seed, then A and B are made of the same matter only in the sense that my parents and I are made of the same matter. This is akin to the pro-choice view that a fetus is part of the woman's body.
ReplyDeleteNormally, you wouldn't expect A and B to be of the same matter. But the atoms in A had to go somewhere. It is quite possible--though exceedingly unlikely--that they went into B, and indeed that every atom in B came from A. That hypothesis is what I am considering.
ReplyDeleteI should note that this is all on the assumption that matter persists in substantial change.
ReplyDeleteIt is similarly logically possible to have a child have the same matter as a parent. Imagine that parent dies, the child grows potatoes on the grave, feeds exclusively on these potatoes, and as it happens eventually all of the child's matter comes from the parent, and all of the parent's matter is in the child.
If 2 substances have the same substantial form, accidents, and matter then it seems to me that they are truly identical. Any "distinction" is only conceptual, as in thinking of oneself as another person.
ReplyDeleteFor an Aristotelian, a difference in initial matter necessitates a difference at least in the accidents of the substance (or so it seems to me).
Pruss is saying this: Imagine there is a seed. As it grows into a tree, it loses all of the matter that made it up when it was a seed. All of that matter then eventually makes up a new seed. Both seeds have the same initial matter, but they are distinct.
ReplyDeleteMaybe we need to distinguish particles from Aristotelian prime matter. I don't know. It seems like the prime matter is used to distinguish when you only have one form per type of being. So, everyone has the numerically same form of humanity, but we are distinguished by our prime matter.
I got that, but even in that hypothetical scenario the seeds have different accidents which flow from a difference, at least spatially and temporally, in their initial matter.
ReplyDeleteIf you reject the distinctness-matter link, what would your principle of individuation be?
ReplyDeleteI am willing to bite the bullet and say that you cannot have two things that have the same origins, where origins include the initial accidents and the causal history.
ReplyDeleteBut I also am skeptical of the need for a principle of individuation in general.
ReplyDelete@Alex Pruss What about immaterial principles of individuation, such as the Scotistic haecceity where the principle is formal, not material?
ReplyDeleteThis is definitely not what Aristotle means, or what Aristotelians should believe:
ReplyDelete1. Only prime matter survives change of substance (Phys I.9), and prime matter isn't individuable nor does it come in packets (counting is by actualities, and prime matter is pure potentiality), as Aquinas gets in Principle of Nature. Any attempt to ascribe "matter as principle of individuation" to primitive parceling of matter cannot possibly be right as a reading of Aristotle.
2. Individuation is therefore by matter only via dimension:
“Hujusmodi autem dimensiones post adventum formae substantialis accipiunt esse terminatum et completum. Quidquid autem intelligitur in materia ante adventum formae substantialis, hoc manet idem numero in generato et in eo ex quo generat; quia remoto posteriori oportet remanere prius; dimensiones autem illae interminatae se habent ad genus quantitatis sicut materia ad genus substantiae.” In IV Sent, d12q1a2qc4co
3. I wrote a thesis on what holds (1) and (2) together for Aristotle: his theory of spatiotemporal contact in generation and corruption (https://www.proquest.com/docview/2174491486/, p69-72)
Anyway, I think this just amounts to the claim that you can't have two substances with the same form in the same place.
But we have some reason to think there is nothing absurd about two substances in the same place at the same time: photons and other bosons can share a state. Presumably a composite made entirely of bosonic matter could as well.
ReplyDelete@Alex Is it true that bosonic particles which overlap spatially still have distinct chunks of matter proper to them, EVEN IN occupying exactly the same location?
ReplyDeleteYour principle of individuation based on origin is also helpful for cosmological arguments. There cannot be more than one being without an origin because there would be nothing to differentiate them if differentiation is based on origin. So, there can only be one being that is not caused.
ReplyDeleteI am not sure I would go there so fast. The beings could be distinguished by their "initial" (i.e., foundational) nature or accidents. (Of course, once we argue that the first being is pure actuality, this won't be an issue.)
ReplyDelete