Hylomorphism and Mereology

Some questions and thoughts about hylomorphism and mereology (parts and wholes).

Is the substance the sum of its material parts?

In some sense, yes, and in some sense, no?

The sum of my prime material parts exists as a potentiality, even in the absence of me and my substantial form.

That sum does not have the potential to be identical (in strictest sense to me) because, for example, I can be actual without its being actual. If the sum and I were strictly identical, we would have to have the same properties at all times and in all worlds.

The sum of my matter has the potential to be a humanoid thing coincident with me, but not to be identical to me. It has the potential to constitute me (in Lynn Rudder Baker’s sense) but not the potential to be me.

Does this create a threat of duplication and causal overdetermination? Are there then two humanoid beings writing this post: me and the sum of my material parts?

Perhaps we could dispel this worry by arguing that the two entities (I and the sum of my material parts) are not mutually independent causes. Couldn’t we say that my actual existence (and my actual powers) are all grounded by the actualization at this moment of my material parts by my substantial form?

This might provide a way out of the survivalist/corruptionist debate, since I am (in this life) a simple thing constituted by a certain complex of material parts. So, after death I could be a simple thing not constituted by any complex of material parts. My soul would be the ground of my existence and powers in both states but never identical to me.

Analogies with van Inwagen’s Material Beings.

Suppose there were living creatures composed of a single particle. We would still need a distinction between a simple thing and a simple living creature—the latter is essentially caught up in a life.

Moral: constitution and composition are metaphysically the same relation: we use the first term when the relation is one-one, and the second term when the relation is many-one

Constitution is just the limiting case of composition.

Suppose we apply van Inwagen’s scheme to a world without simples, a thoroughly gunky. world.  We would need in such a world a distinction between actual and merely potential gobs of gunk. The former are in some way caught up in a life. We could then take a mereologically nihilist point of view, denying that substances have any actual parts.

Can we say that the actual gob of gunky matter and the organism are strictly speaking identical? No, again, we have to have resort to something like a constitution relation.

Could we say that only the proper parts (or only some of the proper parts) of the organism are actual? We would have the same problem with integral parts, like a heart or a hand (homonymy principle). Could we just stipulate that all and only the proper parts of organisms are actual gobs of matter? Yes, that’s a viable solution. In the case of Tib/Tibbles, we can deny that Tib is identical to the tailless part of Tibbles, since, after the amputation, that tailless part is no longer actual.

What about integral parts? We could say that a gob of prime matter is actual iff it is a proper part of some substance and not coincident with any (actual) integral part of that substance.

Or perhaps: x is a proper part of some substance y, and for every actual integral part z of y, either x is a proper part of z or z is a proper part of x.

No, that doesn’t seem right. Better: either x is a proper part of z, or x contains a part that doesn’t overlap z.

What’s wrong with Alex Pruss’s proposal – that matter is simply a corpse-making power, not something that persists through substantial change?

Here the key is Aristotle’s understanding of time and change. Time is the measure of change, and so change must be defined in pre-temporal or non-temporal terms. Change involves the actuality of some potentiality, and this potentiality must also be specified in non-temporal terms. It must be the potentiality of something to be something, not to be succeeded in time or replaced by something, because ‘succession in time’ and ‘replacement’ make essential reference to temporal difference.

Something must be both potentially F (in itself) and actually F (through another, the agent). My matter is potentially human (in itself) and actually human (through my soul).