Tuesday, October 22, 2013

Brains, souls and consciousness

  1. (Premise) I am the only entity that has all the conscious states I presently have.
  2. (Premise) I am breathing.
  3. (Premise) My soul isn't breathing.
  4. (Premise) My brain isn't breathing.
  5. I am neither my soul nor my brain. (2-4)
  6. Neither my soul nor my brain has all the conscious states I presently have. (1,5)
  7. (Premise) If my soul or my brain is conscious, it has all the conscious states I presently have.
  8. So, neither my soul nor my brain is conscious.

If my soul or my brain grounds my consciousness, it does not ground my consciousness by being conscious. It grounds my consciousness by having non-conscious states that ground my consciousness. These non-conscious states will then be more fundamental than my conscious states.

In particular, substance dualists should agree with naturalists that conscious states are non-fundamental. Only non-substance dualists, like hylomorphic dualists and property dualists, have a hope of saying that conscious states are fundamental. And of course a similar argument can be run for other mental states beside the conscious ones.

In practice, some substance dualists will say that I am my soul. If so, then I don't breathe (at most I cause breathing), I don't weigh anything, and so on.

32 comments:

Richard Davis said...

Beautiful argument.

Substance dualists can object (and, to my mind, they can do so with some plausibility) by saying that there are multiple ordinary meanings of the word "I" and that premise 1 and 2 are not both true for the same ordinary meaning of this word.

Heath White said...

This is a really remarkable argument. I agree with RD that substance dualists will dispute premise 1. It would be along the lines of "I am the only entity wearing my wristwatch" but then pointing out that, in one sense, *my wrist* is wearing my wristwatch.

Alexander R Pruss said...

Richard:

Would it not be remarkable to have to say: Nothing that breathes is conscious?

Alexander R Pruss said...

For the record, this is of course an Eric Olson style argument.

William said...

I would contest (5) by asserting that breathing is not a conscious state (in and of itself) which means that (2) does not need to relate to a conscious state. This detaches breathing from consciousness regardless of the ontology of the agent that is breathing.

Alexander R Pruss said...

5 is a logical consequence of 2-4 and Leibniz's law.

William said...

Sleeping Socrates is breathing and not conscious.

Pearl-diving Socrates is conscious and not (briefly, currently) breathing.

Unknown said...

Sweet argument, Alex. It seems that premise 2 (I am breathing) needs to pick out a conscious state. But I don't yet see that it does. I certainly am breathing. And I am conscious of breathing. But being conscious of a state doesn't mean that the state I am conscious of is conscious. I'm sometimes conscious of my heart beating, but my heart beating is not a conscious state. My consciousness of breathing is a conscious state. But there is no reason my soul shouldn't have that state. I am the only thing that has all the conscious states I presently have, but I am not the only thing that has the states I am conscious of. Am I missing something?

Alexander R Pruss said...
This comment has been removed by the author.
Alexander R Pruss said...

Unknown:

I don't understand. Premise 2 doesn't say my breathing is a conscious state, only that I'm breathing. Since my soul or brain aren't breathing, that's all I need to conclude, by Leibniz's law, that I am neither my soul nor my brain.

Richard Davis said...

Dr. Pruss:

Yes, it would be remarkable to have to say 'Nothing that breathes is conscious'. Is this somehow bad for the substance dualist? I take it he can say that not only I(soul) but also I(soul+body) am conscious. Hence, I(soul+body) am conscious and breathing.

Alexander R Pruss said...

On this theory, there seem to be two entities conscious of breathing for each entity that is actually breathing. For body+soul is breathing and conscious of breathing while soul is conscious of breathing but not actually breathing.

I am one of these two entities. Since both have exactly the same conscious states, I have no information on which of them I am. Thus I don't know that I am the breathing entity (soul+body) rather than the non-breathing entity. (This is an adaptation of Merricks' argument against stage theory.)

However, in reality not only am I breathing, but I know I am breathing.

Alexander R Pruss said...

One response to the epistemological argument is to say that "I" (or its mentalese equivalent) is only self-referential when used by the soul+body, and when the soul uses "I", it refers not to itself, but to the soul+body.

That's an odd theory, but I think there may be some literature on it that I haven't explored.

Note that on this theory, I simply cannot ask the question whether I am the soul+body or the soul. For "I" refers to the soul+body even as used by the soul.

However, I can still stipulate a new pronoun "I*" which is always self-referential. And then I can ask: "Am I* breathing?"

analyticphilosopher.com said...

I don't think this is a good argument against the substance dualist or the brain (I prefer cerebrum) theorist. Let's start with the latter. Consider this Olson-style argument (parody?):

1. There's a cerebrum in my room.
2. The cerebrum in my room is thinking.
3. I'm the only thinking thing in my room.

Therefore,

4. I am identical to the cerebrum.

If material objects can think, then it looks like this argument is sound. The materialist will say, 'of course cerebrums think! They are that in virtue of which we think and without which we wouldn't be able to think. If we were to take out your cerebrum and connect it to a machine, thought would continue to be produced. The best candidate, in this case, is the cerebrum.' If this is right, then cerebrums are conscious, and so your (2) is false. It is more accurate to say that the animal in whose skull the cerebrum resides is breathing, but since you're distinct from this animal, you aren't breathing in the same way. Perhaps you breath in the sense that you have a part that breathes.

According to some very plausible interpretations of Christianity, when my body is completely destroyed, *I* continue to exist. But *what* continues to exist when my body has been completely destroyed? Only my mind (or soul). So, after death, the only thing to which I can be identical is my mind. So I'm my mind. But minds are nonphysical substances. So I'm a nonphysical substance. But nonphysical substances don't breath. So I don't breath. Your (2) may be intuitive, but it looks like it is defeated by this argument.

If we are essentially material (or composed of something material), or are essentially animals, then the destruction of our bodies implies our ceasing to exist (there's no such thing as a nonphysical thing that is essentially composed of material, and there's no such thing as a nonphysical animal).

Alexander R Pruss said...

A. If Tibbles is a normal cat, and Tib is the part of the cat in front of the tail plus the cat's soul if it has one (i.e., everything in the cat but the tail), then one could in the same vein argue: "If you destroyed the tail, the cat would surely continue to exist. But all that would be left would be Tib. So, it follows that the cat isn't Tibbles but Tib."

But that's mistaken. The cat is never Tib, neither before nor after the loss of the tail. For instance, an essential property of the cat is that it is supposed to have a tail as a part or aspect of it. That's a property the cat has before and after the loss of the tail. But that is not a property of Tib, either before or after the loss of the tail. So Tibbles is never identical with Tib.

As for the soul and death, there are a couple of stories one can tell.

1. Aquinas' story is that we do not exist when our bodies are destroyed. Our souls exist, but we are not them. We come back into existence once our bodies are resurrected.

2. Or one could say that just as Tibbles, upon loss of tail, is wholly constituted by Tib, but not identical with Tib, so too we after the destruction of the body are wholly constituted by our souls, but not identical with our souls.

3. Or we can deny that anything has proper parts. Tibbles then is an extended simple and there is no such thing as Tib. There is only Tibbles, who changes shape from being tailed to being untailed. At death, we change our manner of existence from being both spiritual and embodied to just being spiritual. (One way to unpack this--I am not endorsing this--is that to be embodied is just to have a limited location. What we call the destruction of the body is either the loss of location or the loss of limits on location.)

B. Why is there no such thing as a nonphysical animal? It seems to me that the characteristics that define animals are primarily normative. Human animals are beings that are supposed to have brain, two arms, two legs, a heart, rationality, etc. No one of these things is individually such that a human animal needs it to exist. Why think that a human animal needs to have any of the material constituents to exist? Why isn't it enough that there exist something that should have brain, arms, legs, heart, etc., but in fact has none of these things?

Alexander R Pruss said...

As for cerebrums, let C1 be any cube in my cerebrum that is 5mm on each side. Let C2 be the rest of my cerebrum. I bet that if you took C2 out and destroyed the rest, I would continue to think. But surely one doesn't want to conclude that I am C2. For then by the same reasoning I am D2, where D2 is my cerebrum minus another 5mm cube D1, and so on. And we don't want to go there.

Richard Davis said...

Dr. Pruss,

I think that on the view that there are two different meanings of "I" --- "I(soul)" and "I(soul+body)" --- it's quite plausible that two tokens of the term "I" which differ in their meanings differ not only in their referents, but in their descriptive contents as well. Typically we have at least some significant degree of introspective access to the descriptive contents of the descriptively-contented terms we deploy. So here's how I can know which I am --- a soul or a body+soul --- for a given token of "I": I just introspect upon the token term "I" in question to determine which of the following two descriptions its descriptive content is more like: 'this mind', 'this thing which has both mind and body as parts'.

I feel that I can actually do this, and I can voluntarily get myself to mean either of these two different things by "I" without going beyond the bounds of the English norms for using this word.

Richard Davis said...

Analyticphilosopher, you seem to move in your argument from "I am identical to mind after death" to "I am my mind". I take it the second of these sentences is present-tensed? If so, then it does not follow from the first sentence unless identity is constant across time. Otherwise, perhaps I am my mind after death, but I am something else (say, some sort of body-mind composite) now.

I don't know of much good reason to think that identity is constant over time. Do you?

Richard Davis said...

Dr. Pruss,

In your argument that Tibbles is not Tib, you seem to rely on the following form of inference:

Tibbles necessarily G's.
Tib does not necessarily G.
Therefore, not Tibbles = Tib.

In your example, G is '... is supposed to have a tail'.

I think this inference form is supposed to be valid as a consequence of Leibniz's Law. So it is only valid if 'necessarily G's' is a predicate about which Leibniz's Law has something to say. Another response to this case (in my opinion, the right response) is to deny that 'necessarily G's' is a predicate of this kind. Roughly speaking, Leibniz's Law applies to all properties and all predicates synonymous with properties, where a property is a predicate in a natural language (a language in which all syntactic simples express metaphysical primitives). But if we translate 'Tibbles necessarily G's' into such a natural language, the translation will roughly read 'For some F, being an F is what it is to be Tibbles and necessarily, some F G's'. There is no predicate in this natural sentence which is plausibly synonymous with 'necessarily G's'. Therefore, 'necessarily G's' is neither a property nor synonymous with any property. So the inference form is invalid, since Leibniz's Law doesn't have anything to say about it. It follows that even while granting that (necessarily Tibbles is supposed-to-have-a-tail) and (not necessarily Tib is supposed-to-have-a-tail) --- and these facts do not change! --- we can nevertheless coherently believe that once his tail is cut off, Tibbles = Tib.

Alexander R Pruss said...

After the operation:
Tib never had a tail as a part of it.
Tibbles had a tail as a part of it.

How can they be the same entity?

Richard Davis said...

'Tib = Tibbles'
'Tibbles had a tail as a part.'
'Tib never had a tail as a part.'

Those three sentences are inconsistent under Leibniz's Law. But the following three are not:

'After the operation: Tib = Tibbles'
'Tibbles had a tail as a part.'
'Tib never had a tail as a part.'

Leibniz's Law has the form 'If x = y, then Fx iff Fy'. So it has nothing to say about the second trio of sentences, since 'After the operation: x = y' doesn't entail 'x = y'.

Richard Davis said...

Apologies --- I've mixed and matched two discussions here. The first post about '... necessarily G's' is relevant to the question of whether Tibbles = Tib even if Tibbles never loses his tail. The second post is, instead, relevant to whether (After the operation, Tibbles = Tib; even though both (i) not Tibbles = Tib and (ii) before the operation, not Tibbles = Tib).

Alexander R Pruss said...

Imagine it is now after the operation.

Then:
Tib never had a tail as a part of it.
Tibbles had a tail as a part of it.

analyticphilosopher.com said...

Thanks for the response. I'll take the points in reverse:

Aquinas' story is implausible. After death, there remains a mind that is psychologically continuous with me, has my thoughts, beliefs, desires, memories, etc. But, on this view, it isn't me! So a new person suddenly pops into being (surely what exists after death is a person. After all, it's conscious and has all the relevant psychological properties that are sufficient for personhood). Suppose that, just before I die, I begin to think 'IIIIIII think, therefore, I exist' such that I am holding the 'IIIII' as I die. It is very implausible to suppose that it refers to me just before death, and to some other person after death (a friend of mine has made this point here: http://analyticscholastic.blogspot.com/2013/06/why-i-am-substance-dualist.html).

Not sure how the constitution view would work after death (it might make sense before death, when you've got an animal body). The only relevant thing that exists after death is your mind (or soul). So if you're not identical to it, to what are you identical?

If you deny that I have proper parts, then you're committed to the view that you don't have a head and brain. But the proposition that you have a head and brain is just as plausible as the proposition that you breath. A view's requiring this move seems to me to count against it.

"Why is there no such thing as a nonphysical animal?" Well, because animals are wholly and essentially material objects. I have no idea what an immaterial cat is. You say that it's something that ought to have certain biological properties, right? Here's a problem: Suppose at t God destroys every animal body, but every animal soul continues to exist. This is a possibility. If God is omnipotent, he could've done this: the first moment of the world is t (the time of the actual world during which only animal souls exist). Your view seems to imply that it is possible that there be something that is an animal and was never alive or had any biological properties. This seems to me to be counterintuitive.

I agree that the cat is never Tib, but only because Tib, like the cat, is too big. If we suppose that cats are wholly material (I reject this), then the following argument is sound:

Kenny is my cat and he is the only thing in my room.

1. There's a cerebrum in my room.
2. The cerebrum is conscious.
3. Kenny is the only conscious thing in my room.
So,
4. Kenny is the cerebrum.

On your criticism about the cerebrum view (which I think is clearly false), I agree that the cerebrum is too big still. So let 'cerebrum' be whatever is doing the thinking when the cerebrum is in a disembodied state. This may be a part of the cerebrum.

I am inclined to think this argument is sound:

5. There's a mind in my room.
6. The mind in my room is thinking.
7. I'm the only thinking thing in my room.
So,
8. I am my mind.

But minds are nonphysical substances. So I'm a nonphysical substance. You might deny (5) because nonphysical things aren't spatially located. Fine:

9. There's a mind uniquely related to this body which is in my room.
10. This mind is thinking.
11. I am the only thing uniquely related to this body that is thinking.
Therefore,....

Denying (11) implies too many thinkers. Denying (10) seems to me to be utterly implausible. It seems to me that minds do think (isn't that what minds are?).

Alexander R Pruss said...

1. That's a good criticism of the Aquinas view. I guess Aquinas could--but certainly does not--deny that the soul after death is conscious. Instead, he could say that the soul has states of the sort that would ground a person's consciousness if the soul were in a person.

2. I don't see the problem with the constitution view. The point of constitution views is to allow that one thing is constituted by another that is wholly coincident with it, e.g., the statue by its clay. Besides, if we adopt some four-dimensionalist ontology, there is nothing significant about the fact that X and Y happen to be made of the same matter on some temporal cross-section.

3. I can say that I have a wrinkle on my face or a hole in my skin without being committed to an ontology on which there really are wrinkles and holes. Presumably, one will have a semantics on which the truth of "I have a wrinkle" isn't grounded in a relation of me to a distinct object, but is instead grounded in one's being wrinkled. Likewise for heads and brains: that I have a head or a brain isn't grounded in a relation of me to a distinct object, but is grounded in my being headed or brained. :-)

4. If you're inclined to think the name of your cat refers to its mind, then just replace the cat with some animal that doesn't have a mind. Or, if you believe in artifacts, just suppose Tibbles is a plush cat.

5. We dig with shovels and think with minds. Our shovels don't dig and our minds don't think.

Richard Davis said...

Dr. Pruss,

You said:

"Imagine it is now after the operation.

Then:
Tib never had a tail as a part of it.
Tibbles had a tail as a part of it."

I don't think that the concatenation of a time operator with a tensed clause is true. Thus,

'Tib never had a tail as a part of it' is true, but
'At some time, Tib never had a tail as a part of it' is false.

The same holds if we replace 'At some time' with 'Then'. So I'm denying the claim 'Then, Tib never had a tail as a part of it'.

There's an exception for predicates like '... is ten years old' or '... has not yet G'd'. But I think

'Right now, I am ten years old'

means

'There are ten years between the time of my birth and right now (and I have existed continuously throughout the period)'.

So it doesn't have the logical form 'Now, Fx' for any tensed predicate F. Likewise

'Tib has never yet had a tail as a part of it'

means

'There is no time prior to right now at which Tib has a tail as a part of it.'

This sentence is true, but even given the truth of 'Right now, Tibbles = Tib', it is consistent with

'Tibbles has had a tail as a part of it',

i.e.,

'There is some time prior to right now at which Tibbles has a tail as a part of it'.

Richard Davis said...

I.e., because of the form of Leibniz's Law, the following three sentences are consistent:

'There is some time prior to right now at which Tibbles has a tail as a part'
'There is no time prior to right now at which Tib has a tail as a part'
'Right now, Tibbles = Tib'.

These are synonymous to the only true readings of

'Right now, Tibbles has had a tail as a part'
'Right now, Tib has not yet had a tail as a part'
'Right now, Tibble = Tib.'

So these last three sentences are consistent, too. There's no way to use 'never has' instead of 'has (yet) had' in order to cause an inconsistency while preserving the truth of the premises, since sticking a 'never' under a tense operator typically just causes the resulting sentence to be false.

(You could get a true sentence by saying 'has never had' rather than just 'never has', but then the sentence would mean the same thing as the examples above; so it, too, would be consistent.)

analyticphilosopher.com said...

A few responses:

Another point about Thomas' view: When one prays to St. Thomas or any of the other saints, his view implies that they're praying to different people.

I am talking about what the constitution view would be when your body is totally destroyed. After this event, the only part of you that persists is your soul. So you say you're constituted by your soul but you're not identical to it. My question is, to what are you identical if not your soul (when you're dead)? On the example you gave, viz. the statue and lump, the statue is identical to, say, David (which consists in having a certain shape and other properties) and is constituted by the lump of clay. How does this work when there's no matter whatever associated with you?

There's no problem when it comes to unconscious or mindless animals. They're just wholly material objects.

"We dig with shovels and think with minds. Our shovels don't dig and our minds don't think."

This is about as convincing as: 'We dig with shovels and think with animals, but shovels don't dig and animals don't think.' I'd think this only because I already believe that we aren't animals, and you'd think that only because you deny that we're minds. But if we are minds, then, of course, our minds think, because we think. If we are animals, then, of course, they think because we think. In any case, there's a good argument that minds think. Again, when the body is completely destroyed, it is possible that conscious thought continues. In this case, what's doing the thinking? ONly the mind exists. So the only candidate is the mind and so the mind is thinking. But if minds can think disembodied, why not embodied? Why does its having fleshly surroundings suddenly entail that it lacks an ability it would otherwise have? On your view, what is an angel? Is an angel an unembodied mind? If so, don't minds think if angels think? If their minds can think, why can't ours?

Alexander R Pruss said...

Yeah, I don't think Thomas's view fits with the Catholic tradition that well (though of course he thinks it does).

Are you assuming four-dimensionalism is false? If four-dimensionalism is true, then on the n view the disembodied soul is a part of a four-dimensional embodied individual. It just so happens that that four-dimensional individual has no material parts at those times at which the soul exists in its disembodied state. Why would that be a problem?

On a three-dimensionalist view, I can give a variant of the story about the statue and the clay. What makes the clay constitute a statue is that (a) the clay has a certain causal history--it was made by an artist with artistic intentions and (b) the clay maintains a configuration minimally expressive of those artistic intentions. What makes the soul constitute a person is that (a) the soul has a certain causal history--it came into existence as the soul of that embodied person and (b) the soul maintains a configuration minimally expressive of its connection with that embodiment (e.g., it has the normative property of being such that it should be embodied in that body).

Now, what if there was just the soul without the causal history? I don't know that that's possible.

analyticphilosopher.com said...

Thanks again for the response. I've enjoyed the discussion. Just a minor point:

"Now, what if there was just the soul without the causal history? I don't know that that's possible."

What's your view on omnipotence? As I wrote before, it doesn't seem to me to be incoherent to suppose that God might've created a world whose first moment is relevantly similar to the time at which all souls become disembodied. So why can't this be done? That is, why can't God create your mind without its having ever been associated with a body? I think an accurate account of omnipotence is going to have to involve more than mere logical possibility, but the fact that what I've described is coherent seems to me to be evidence that God can do it. Moreover, the fact that we know minds can exists disembodied (if you think we do know this) would be good evidence, it seems to me, that it is possible that minds exist without ever having been associated with a body.

Alexander R Pruss said...

Could God create a heart without creating the rest of the animal? He could certainly create a bunch of cells arranged as a physical duplicate of a heart. But that's not enough for creating a heart. For a heart is defined in part by its teleology: it exists to further the oxygenation of a particular organism. Without there being such an organism, it would just be a bunch of cells, not a heart. (Tough question what happens metaphysically to a heart in a transplant, but there are multiple options compatible with what I said.)

But just as a heart has a teleological connection to a particular body, so does (and even more so) a soul. The soul is the form of the body after all. So in the absence of a body to have a teleological connection to, it does not seem that one can have soul.

Now maybe a heart or a soul could be created that has a teleological connection to an organism that in fact doesn't exist. There are tough questions here about relations to nonexistent objects.

The above is more plausible if one accepts essentiality of origins, I guess.

Dagmara Lizlovs said...

You guys sure love to complicate the really simple stuff. :-)