Thursday, April 9, 2015

Can something material become immaterial?

Two angels are playing chess. They are immaterial, but have the causal powers of moving physical pieces on the board. Along comes a big snake and swallows the board. No worries: the angels keep on playing, but now the positions of the chess pieces are kept track of in their minds instead. So the king, say, was first a material object. But the king then became an object wholly constituted by the angels' thoughts, and hence immaterial. And it is the same king. While in chess you can get a new queen by promoting a pawn, you don't get a new king within a game.

(Of course, I suspect that the true ontology doesn't include artifacts like chess kings.)


Mark Rogers said...

It seems to me that the angels would not know if the king was material or immaterial, only that they observe the king as immaterial.

Heath White said...

Does the second person of the Trinity go from being immaterial to (partly) material?

Alexander R Pruss said...

Maybe, though it's not a temporal change.

Unknown said...

On your view (which I think is hylomorphic), between death and resurrection, do humans become immaterial? Do they become identical to their souls? I have tried to make sense of Aquinas's view in this regard, and I THINK that might be the best way to understand him (though sometimes it sounds as if, e.g., Socrates's soul or intellect exists immaterially after his death and is not identical to Socrates).

Austin said...


I think a Thomist would concede that the soul of a human being between death and resurrection is not complete. Since the material body is part of the essence of a human being (and thus the essence of Tully, or Austin), one's soul between death and resurrection is not essentially the same as during their life.

I think...

SMatthewStolte said...

It doesn’t seem to me like chess kings are material at all, any more than this sentence blog post is material.

Material things cannot be in two places at once, and they seem to occupy something like three-dimensional, Euclidean space.

Alexander R Pruss said...


Humans in this life are partly material and partly immaterial, and in the interim state they become solely immaterial. I wouldn't say that they become souls--that would lead to the contradiction that they become identical to something that is now a proper part of themselves and hence to something that isn't themselves. Maybe the thing to say is that they come to have no proper parts other than the soul.

Alexander R Pruss said...


Any one chess king occupies only one square at a time. Of course, there are kings in multiple games. But they are different kings, just as the pawns in a single game are different pawns.

Unknown said...


Ah, I see. Thanks. I have another question, if you don't mind, related to your last sentence about artifacts. How is your view theologically compatible with transubstantiation, specifically with respect to the substance of the bread (which is just atoms arranged in a certain way, or fields...and doesn't have a material substance, or does it?) If you choose to respond, I'm not looking for anything in detail, I'm just curious.

Alexander R Pruss said...

Well, all reality--except for free-floating accidents if there are any--is grounded in substances.

So while bread may not be a substance, its existence is grounded in substances, either really big ones--fields--or really small ones--particles.

In the particle case it's easier: the particles just cease to exist, but things behave in their former vicinity as if they were still there.

In the field case, I don't want to say that the fields cease to exist, since they are global fields. Rather, I would say either that the fields either withdraw from where the bread was, leaving a hole in the fields, or else just cease to have the sorts of features as grounded the bread's existence. Normally if the fields do either of these things, the bread ceases to exist and disappears. In this case, it ceases to exist but, miraculously, doesn't disappear--its appearance remains in the bread's absence.

Unknown said...


Thanks. I'm still a little confused. I think you have said in other posts that one should deny there are artifacts (pipes, etc.) I'm attracted to that view myself. But in the last remark to me you say "[the bread's] existence is grounded in substances." That sounds like you do believe in at least one artifact--bread (though it's not a substance). Now, I'm unsure of what the official doctrine of transubstantiation is, but as it is sometimes expressed, there is a substantial change of the bread. So my original question was partly out of theological ignorance about whether one has to be committed to the existence of bread, and ignorance of how you handled this if you denied that there is bread.

Alexander R Pruss said...

I think that when the ordinary person, or the theologian for that matter, says at breakfast "There is bread on the table", they are saying something true, even if in the ontology room we would deny there being bread or tables.

That true thing is grounded in facts about particles or fields. The absence of these facts would then, in turn, ground the truth of the ordinary sentence "There is no bread here."

So I get the claim that there was bread and there is no bread, in the ordinary sense. And I think it's a standard principle of Catholic exegesis of doctrine that we should typically take words in their ordinary meaning, so the claim "There is bread before consecration" should not be taken in the sense of the ontologist.

But I think you are asking about something further. Sometimes transsubstantiation is phrased in terms of a *change*. It is not completely clear to me that that's part of the doctrine, except in a manner of speaking (think of: "The clouds on the movie screen have changed into a pastoral scene"; all we mean is that the imagine of the clouds was replaced by the image of the pastoral scene).

When Pope Paul VI in the his Credo of the People of God discusses the doctrine, he says that the two central ideas are the real presence of Christ and the real absence of bread and wine. What I said fits with that.

But what if we insist on the change as a required part of the doctrine? Well, it's not quite clear what this part would mean. Aristotelian thought would have been a primary philosophical approach by the fathers at Trent. But on a natural Aristotelian view what makes it true that A substantially changes into B, rather than just being replaced with B, is that A's matter persists, first with the form of A and then with the form of B. However, the Fathers of the Trent would surely not have meant that *this* is what happens in transsubstantiation: they surely did not think the matter of the bread persisted after the change, and became a part of the body of Christ.

So the fathers at Trent couldn't have thought of the change as very close to ordinary substantial change.

Maybe what makes something be a matter of change rather than mere replacement is some kind of appropriate explanatory or causal connection. Here we have something like that: the location of Christ's body after consecration is explained by the location of the bread prior to consecration. Is that enough? I am not sure, but it might be.

Unknown said...

Thanks, you addressed precisely what I was wondering about.

SMatthewStolte said...

If kings are material beings, then the very same king would occupy two spaces at once in the case of mail chess. Of course, there is the physical thing called the ‘king’ too, but that just seems to be an instrument for communication.

Alexander R Pruss said...

Presumably, in that case the king is bilocated or just a scattered object. There is nothing troubling about a scattered object.

If the king is always an immaterial object, then either it is Platonic and always exists, or it's created by us when we play.

It's not Platonic. For in simultaneous games, there are at least as many black kings as there are games. And so we would have an unruly multiplication of Platonic objects. Moreover, we would have the curious puzzle of how it is that it happens that we play with the black king we do rather than with one of the infinitely many other black kings.

It's not created by us. For it's not that easy to make immaterial objects!

Alexander R Pruss said...

I take back the argument against the second horn of the dilemma. That's a problem for my reading of the situation, too. :-)

But in any case, note that it's just as puzzling how two people can have access to the same non-Platonic immaterial objects as how the same king can be found on two boards.

SMatthewStolte said...

I agree that this is puzzling.