Can you list what these definitions are? I have not read Aristotle directly so all I know is how modern proponents of the “Aristotelian/Thomist tradition” define substance, which is the definition I have been attempting to defend in this thread.
It is something I noticed in different contexts. When Aristotle talks of living beings as substances different principles are invoked from when he speaks of “inorganic” substances. I’m by no means the first to notice this and I recently came across an article (Stanford Uni site I believe) that isolates 4-5 different ways that Aristotle speaks of substance over his corpus at different stages in his works. I’ll see if I can find it again.
I will attempt to illustrate the point with the figure attached to the bottom of this post. In Fig. A you define the individual atoms as substances, so you have 2 hydrogen substances and 1 oxygen substance. In Fig. B you define the H2O as the substance, so you have 1 blue H2O substance. In Fig. C, you attempt to define both the atoms and the H2O as substances, but then you have two substances occupying the same matter, since the oxygen atom is both an oxygen substance and an H2O substance (signified by the blended colors). So you either have to accept that the atoms are the substances and H2O’s properties are purely accidental, or you have to accept that H2O is the substance and the atoms are virtually present.
I don’t really understand your point
.
I am suggesting two lines of enquiry…
(a) In a H20 molecule we are no longer dealing with individual atoms.
However, in bulk H20 (ie water) a certain % of these molecules at any given time has separated into individual ions…including individual atoms of Hydrogen as H+.
(Also, even our individual H20 molecule could at any time split into ions).
In this scenario I accept that in a coherent molecule of H20 we are no longer dealing with the active presence of hydrogen.
(b) In this scenario we could look in a purely mechanistic way at the H2O molecule.
If we put a knife through one of the HO bonds we would end up with either:
(i) a H atom (if the knife cut through when the shared electron was on the H side) OR
(ii) a H+ ion (if the electron was on the O side at the time of cutting).
Keep in mind that, for the Thomist at least, the substantial form is part of what makes the thing in question actually exist. Without substantial form, you just have pure potency, which is not a thing at all. So you can’t have two substantial forms on the same matter since you would be causing the thing in question to exist twice over.
You’ve left time out of consideration. I suppose I am saying, in the above examples, that at one time its one substance at another time its another. That is what I mean by dynamic equilibrium between ionised and molecular states.
But you were defining water as the “dynamic equilibrium of H2O, H+, OH-, and other related molecules/ions.”
Yes. But I wasn’t really defining water, rather just describing some pertinent and unavoidable behaviours discoverable in that everyday “thing” we call water.
That equilibrium is the unifying form of all the underlying parts, making them really water,
Well you are talking about a forest here…I was only observing some trees…
so the properties of all those individual parts are present only virtually in the equilibrium
I don’t really understand what you mean by “virtually” here.
I would observe that all the molecules/ions mentioned above are actually present at any given time. And in so far as ions can reform into molecules, and molecules into ions…then ions are also potentially present in molecules and molecules are potentially present in ions.
since the equilibrium is what is defining the water substance using the above definition.
I don’t think so. The equilibrium is essentially an aggregated mixture of actual substances dynamically acting upon each other. You infer a single forest…I just see a lot of trees interacting eternally.
If the underlying molecules and ions are substances as well, then they are counted twice
I don’t really understand what you mean here.
If the molecules and ions are the real substances, then the equilibrium is only accidental.
This is worth teasing out I think - though I don’t understand how you are defining equilibrium here - let alone your distinction between accidental and substantial equilibrium.
For me “equilibrium” is a special type of reversible two-way change unexplored by Aristotle. Aristotle, it seems, assumed irreversible changes were substantial (eg burning) …and reversible changes were accidental (water to steam, steam to water).
But modern science would disagree.
Burning can be perfectly reversible (quicklime/slaked lime, burnt mercury) as Priestly discovered.
The alleged clear line between substantial and accidental change is therefore blurred in equilibriums … esp at the atomic level. Maybe Aristotle’s theory of substance (which is meant to be non atomic in principle) does not cope well when we look at reality at the atomic level as Chemists are want to do.
. Anyway, the point I was making was a metaphysical one and not a scientific one. I will attempt to illustrate the point with the figure attached to the bottom of this post. In Fig. A you define the individual atoms as substances, so you have 2 hydrogen substances and 1 oxygen substance. In Fig. B you define the H2O as the substance, so you have 1 blue H2O substance. In Fig. C, you attempt to define both the atoms and the H2O as substances, but then you have two substances occupying the same matter, since the oxygen atom is both an oxygen substance and an H2O substance (signified by the blended colors). So you either have to accept that the atoms are the substances and H2O’s properties are purely accidental, or you have to accept that H2O is the substance and the atoms are virtually present.