## Wednesday, October 2, 2019

### An Aristotelian account of proper parthood (for integral parts)

Here it is: x is a proper part of y iff x is informed by a form that informs y and x's being informed by that form is derivative from y's being informed by it.

MJ said...

So, if my arm is a proper part of 'me', then my arm is informed by the form that informs 'me', and my arm's being informed by that form is derivative of 'me' being informed by it.

But if my arm is informed by the same form that informs 'me', wouldn't it follow that my arm has a form that's informed by the same form that informs 'me'? But perhaps I'm misunderstanding what you mean by 'informed'. It seems that it's plausible that the metaphysician could plausibly deny that my arm has a form, which might undercut the idea that it couldn't be informed by the same form that informs 'me'. And I also could be misunderstanding what is meant by 'proper part' such that things like 'my arm' couldn't be proper parts.

Alexander R Pruss said...

The functioning, and even existence, of my arm is controlled by my form. So my arm is a part of me.

Philip Rand said...

Interesting...

Since that is the case, then...

How would your Aristotelian definition apply to the rubber hand experiment?

Alexander R Pruss said...

The rubber hand is not informed by my form.

Michael Staron said...

You might have meant to restrict "form" here to "substantial form." But if not, I think this has an interesting consequence. On a more reductionist picture, I am white because my integral parts are white - in terms of "form," I am informed by the accidental form White because my integral parts are informed by the accidental form White. However, your account seems to reverse the order of explanation: my integral parts are informed by the accidental form White because I am informed by the accidental form White. [The order is reversed I think because (1) my integral parts are proper parts of me in the first place because (i) they are informed by White and (ii) they are informed by White in virtue of White informing me, and (2) if I have a certain characteristic, F, because my integral parts have F, then I cannot appeal to my having F to explain my having those parts in the first place.]

Danny said...

Does this argument require that the form is holenmerically extended throughout y?

Michael Staron said...

I don't think so. One reason not is, on the account given by Dr. Pruss above, substantial form and prime matter are not integral parts that are proper parts. I do not believe that my prime matter, for example, is informed with my substantial form in virtue of my being informed by my substantial form. In this case, the order of explanation is reversed: I am informed by my substantial form because my prime matter is informed by my substantial form.

I bring this up because it seems possible that I can be informed by an accidental form in virtue of my prime matter being informed by an accidental form (e.g. my quantity). And I do not think that my prime matter's being informed by an accidental form requires that the form is holenmerically extended in me, partly because I do not think it makes sense to treat prime matter as being holenmerically extended in me. Maybe I am wrong about this. I am not sure.

Philip Rand said...

Michael Staron

There exists a non-zero probability that a particle from your body would be measured at the other end of the universe.

Philip Rand said...

Michael Staron

The problem when you refer to holenmerically extended is that it would not be possible to construct a Lagrangian from the definition, on account though the definition looks formal it isn't....