Mind – Page 10 – Maverick Philosopher

The Ultimate in Self-Alienation

Dennett is so alienated from his own nature as a conscious, thinking being that he denies qualia and holds an ascriptivist theory of intentionality. It is amazing how, in the grip of a theory, one can bring oneself to deny the self-evident.

Homunculus

The soul anthropomorphized:

Are There Indexical Facts? Are They a Threat to Materialism?

1. Ernst Mach Spies a Shabby Pedagogue. In The Analysis of Sensations (Dover, 1959, p. 4, n. 1) Ernst Mach (1838-1916) offers the following anecdote:

     Not long ago, after a trying railway journey by night, when I was
     very tired, I got into an omnibus, just as another man appeared at
     the other end. 'What a shabby pedagogue that is, that has just
     entered,' thought I. It was myself; opposite me hung a large
     mirror. The physiognomy of my class, accordingly, was better know
     to me than my own.

When Mach got on the bus he saw himself, but not as himself. His first thought was one expressible by 'The man who just boarded is a shabby pedagogue.' 'The man who just boarded' referred to Mach. Only later did Mach realize that he was referring to himself, a thought that he might have expressed by saying, 'I am a shabby pedagogue.'

Clearly, the thought expressed by 'The man who just boarded is shabby' is distinct from the thought expressed by 'I am shabby.' After all, Mach had the first thought but not the second. So they can't be the same thought. And this despite the fact that the very same property is ascribed to the very same person by both sentences. The difference emerges quite clearly if we alter the example slightly. Suppose Mach sees that the man who has just got on the bus has his fly open. He thinks to himself: The man who has just boarded has his fly open, a thought that leads to no action on Mach's part. But from the thought, I have my fly open, behavioral consequences ensue: Mach buttons his fly. Since the two thoughts have different behavioral consequences, they cannot be the same thought, despite the fact that they attribute the very same property to the very same person.

But if they attribute the same property to the same person, what exactly is the difference between the two thoughts?

Linguistically, the difference is that between a definite description ('the man who just boarded') and the first person singular pronoun 'I.' Since the referent (Frege's Bedeutung) is the same in both cases, namely Mach, one will be tempted to say that the difference is a difference in sense (Frege's Sinn) or mode of presentation (Frege's Darstellungsweise). Mach refers to himself in two different ways, a 3rd-person objective way via a definite description, and a 1st-person subjective way via the first-person singular pronoun.

If this is right, then although there are two different thoughts or propositions, one indexical and the other non-indexical, it might seem that there need only be one fact in the world to serve as truth-maker for both, the fact of Mach's being shabby. This is a non-indexical fact. It might seem that reality is exhausted by non-indexical facts, and that there are no such indexical or perspectival facts as those expressed by 'I am shabby' or 'I am BV' or 'I am the man who just got on the bus.' Accordingly, indexicality is merely a subjective addition, a projection: it belongs to the world as it appears to us, not to the world as it is in reality. On this approach, when BV says or thinks 'I,' he refers to BV in the first-person way with the result that BV appears to BV under the guise of 'I'; but in reality there is no fact corresponding to 'I am BV.'

2. But is this right? There are billions of people in the world and one of them is me. Which one? BV. But if the view sketched above is correct, then it is not an objective fact that one of these people is me. That BV exists is an objective fact, but not that BV is me. BV has two ways of referring to himself but there is only one underlyingobjective fact. Geoffrey Maddell strenuously disagrees:

     If I am to see the world in a certain way, then the fact that the
     world seen in this way is apprehended as such by me cannot be part
     of the content of that apprehension. If I impose a subjective grid
     on the world, then it is objectively the case that I do so. To put
     it bluntly, it is an objective fact about the world that one of the
     billions of people in it is me. Mind and Materialism, 1988, p.
     119.)

Maddell's point is that the first-person point of view is irreducibly real: it itself cannot be a subjective addition supplied from the first-person point of view. It makes sense to say that secondary qualities are projections, but it makes no sense to say that the first-person point of view is a projection. That which first makes possible subjective additions cannot itself be a subjective addition.

Consider the phenomenal redness of a stop sign. It makes sense to say that this secondary quality does not belong to the sign itself in reality, but is instead a property the sign has only in relation to a perceiver. In this sense, secondary qualities are subjective. But to say that subjectivity itself, first-person perspectivity itself, is a subjective projection is unintelligible. It cannot belong to mere appearance, but must exist in reality. As Madell puts it, "Indexical thought cannot be analysed as a certain 'mode of presentation', for the fact that reality is presented to me in some particular way cannot be part of the way in which it is presented." (p. 120)

3. Trouble for materialism. According to materialism, reality is exhausted by non-indexical physical facts. But we have just seen that indexical thoughts are underpinned by indexical facts such as the fact of BV's being me. These facts are irreducibly real, but not physically real. Therefore, materialism is false: reality is not exhausted by non-indexical physical facts.

Jaegwon Kim on Reductionism and Eliminativism

I've been studying Jaegwon Kim's Physicalism, or Something Near Enough (Princeton UP, 2005). Here are some notes and questions.

1. It's clear that mental causation must be saved. If Kim is right that nonreductive physicalism is not viable, then by his lights our only hope of saving mental causation is via "physical reductionism." (159). It is of course easy to see how such reductionism, if true, would save mental causation. Surely my desire for a beer together with my belief that there is beer in the reefer are part of the etiology of my getting out of my chair and heading to the kitchen. If beliefs and desires are physical states, then there is no in-principle difficulty in understanding the etiology of my behavior. Reductionism insures the physical efficacy of the mental. What was a thorny problem on dualist approaches is no problem at all for the physical reductionist.

2. At this point some of us are going to wonder whether reductionism collapses into eliminativism. I tend to think that it does. Kim of course must disagree. His project is to find safe passage between nonreductive physicalism and eliminativism. But first I want to concede something to Kim.

3. Kim rightly points out (160) that we cannot assume that the mental cannot be physical in virtue of the very meaning of 'mental.' We cannot assume that 'mental' means 'nonphysical.' The following argument is not compelling and begs the question against the physicalist:

Beliefs and desires are mental
Whatever is mental is nonphysical
Ergo
Beliefs and desires are not physical.

The physicalist finds nothing incoherent in the notion that what is mental could also be physical. So he will either reject the second premise, or, if he accepts it, deny the first and maintain that beliefs and desires are not mental in the sense in which his opponents think they are. It seems clear, then, that one cannot mount a merely semantic argument against the physicalist based on a preconceived meaning of 'mental.'

4. Is my present state of consciousness real and yet reducible to a pattern of electrical activity in a network of neurons? Can we secure reduction without elimination? Reductionist: there are Fs but what they are are Gs. Eliminativist: There are no Fs. There at least appears to be a difference in these two sorts of claims. Kim claims that "There is an honest difference between elimination and conservative reduction." (160) Phlogiston got eliminated; temperature and heat got reduced. Witches got eliminated; the gene got reduced. The reductionist thinks he can secure or "conserve" the reality of the Fs while reducing them to the Gs. In the present case, the physical reductionist in the philosophy of mind thinks that he can maintain both that mental states are real and that they reduce to physical states.

5. Let's note two obvious logical points. The first is that identity is a symmetrical relation. The second is that reduction is asymmetrical. Thus,

I. Necessarily, for any x, y, if x = y, then y = x.
R. Necessarily, for any x, y, if x reduces to y, then it is not the case that y reduces to x.

It is clear, then, that identity and reduction are not the same relation. And yet if particular a reduces to particular b, then a is nothing other than b, and is therefore identical to b. If you think about it, reduction is a strange and perhaps incoherent notion. For if a reduces to b, a is identical to b, but, since reduction is asymmetrical, b is not identical to a! Reduction is asymmetrical identity. Amd that smacks of radical incoherence. This is what inclines me to say that reduction collapses into elimination. For if a reduces to b, and is therefore identical to b, while b is not identical to a, then it follows that there simply is no a. And so if my present mental state reduces to a pattern of electrical activity in a network of neurons, then my mental state does not exist; all that exists is the electrical activity.

6. Kim wants to have it both ways at once. He wants mental states to be both real and reducible. He wants to avoid both eliminativism and dualism. My claim is that it is impossible to have it both ways. Kim thinks that reduction somehow "conserves" that which is reduced. But how could it? If my desire for a beer is nothing other than a brain state, then then it is a purely physical state and everything mental about it has vanished. If 'two' things are identical, then there is only one thing, and if you insist that that one thing is physical, then it cannot also be mental.

7. My present thinking about a dog is intrinsically intentional, intrinsically object-directed. But no physical state is intrinsically object-directed. So, by the Indiscernibility of Identicals, my present thinking about a dog simply cannot be identical to any brain state, and so cannot reduce to any brain state. Kim of course thinks that intentional properties are functionalizable. I have already argued against that view here. Whatever causal role my thinking about a dog plays in terms of behavioral inputs and outputs, causal role occupancy cannot be make makes my thinking intentional. For it is intentional intrinsically, not in virtue of causal relations.

8. Kim speaks of the functional reducibility of intentional/cognitive properties. But surely it is not properties that need reducing but particular meetal acts. Properties are not conscious of anything. Nor are causal roles. It is the realizers of the roles that are bearers of intentionality, and it simply makes no sense to think of these as purely physical.

9. Once one starts down the reductive road there is no stopping short of eliminativism. The latter, however, is surely a reductio ad absurdum of physicalism as I explain in this post on Rosenberg's eliminativism.

The Irreducibility of Intentionality: An Argument From the Indeterminacy of the Physical

If it could be made to work, materialism would be attractive simply on grounds of parsimony. We all agree that entities, or rather categories of entity, ought not be multiplied beyond necessity. There are those who will intone this Ockhamite principle with great earnestness as if they are advancing the discussion when of course they are not: the real issue concerns what is needed (necessary) for explanatory purposes. If you agree that philosophers are in the business of explanation, then I hope you will agree that a good explanation must be categorially parsimonious but not at the expense of explanatory adequacy.

So we ought not introduce irreducibly mental items and/or abstracta if we can get by with just material items By 'get by' I mean explain in adequate fashion all that needs to be explained: consciousness, self-consciousness including self-reference via the first-person singular pronoun, qualia, intentionality, conscience, mystical and religious experience, the applicability of mathematics to the physical world, the normativity of logic, normativity in general, the existence of anything in the first place, the emergence of life . . . .

My main interest is negative: in showing that materialism doesn't work. Please don't respond by saying that some other theory (substance dualism, say) doesn't work either. For the issue is precisely: Does materialism work? If theory T1 is explanatorily inadequate, its deficiencies cannot be made good by pointing out that T2 is also inadequate. This is an invalid argument: "Every alternative to materialism is inadequate; therefore we should embrace materialism despite its inadequacies." Wouldn't it be more reasonable under those circumstances to embrace no theory?

One more preliminary point. If materialism is explanatorily adequate, then we ought to embrace it, and dispense with God, the soul, and the denizens of the Platonic menagerie. For if materialism were adequate, there would be no reason to posit anything beyond the material. But if materialism is not adequate, then we do have reason for such posits.

The following argument is my interpretation of remarks made by Edward Feser in his Philosophy of Mind: A Short Introduction (One World, 2005), pp. 156-159)

1. Consider a representation such as a picture. You draw a picture of your mother. The picture represents her: it is of or about her, and it would remain about her even were she to cease to exist. The picture is a physical object with physical properties: the paper is of a certain size and shape and texture, the ink of a certain chemical composition, the lines have a definite thickness, etc. Now I would insist that these physical features cannot be that in virtue of which the picture represents your mother: they cannot be that in virtue of which the physical item is a representation. For it makes no sense to ascribe intrinsic semantic or intentional properties to merely physical items. But even if I am wrong about this, there remains a problem for a materialist theory of representation.

2. Suppose a 'copycat' comes along and makes an EXACT copy of your picture of your mother. The copycat's intention is not to represent your mother; his intention is merely to represent your representation of your mother. Now there are two pictorial representations, call them R (the original) and R' (the copy). The question arises: Is R' a representation of your mother, or is R' a representation of R? Suppose a second copycat comes along and produces a second copy R''. Does R'' represent R' or R or your mother? The situation is obviously iterable ad infinitum.

3. Clearly, there is a difference between saying that R' represents your mother, a human being, and saying that R' represents R, a nonhuman drawing of your mother. The reference is different in the two cases. But the reference is indeterminate if we go by the physical properties of the representations alone. Suppose I hand you two drawings of your mother, one an exact copy of the other, but you do not know which is the orignal and which is the copy. You cannot, by inspection of these drawings, tell which is which. Thus you cannot determine the reference from the physical properties.

4. The point is generalizable to other types of representations. Suppose I say 'cat' to refer to a cat and my copycat brother says 'cat' simply to copy me. If my brother mimics me perfectly, then it will be impossible from the physical properties of the two word-sounds to tell which refers to a cat and which does not.

Please do not say that we are both referring to a cat. For my copycat brother is a mere copycat: his intention is merely to reproduce the word-sound I made. To make it even clearer, replace my brother with a parrot who happens to be a perfect mimic. No one will say that the 'cat'-token produced by the parrot refers to a cat. The parrot is just an animate copy machine.

The same goes for any physical representation. Suppose a pattern of neural firings is taken to be a representation of X. An exact copy of that pattern needn't be a representation of X; it could be a
representation of the original pattern. In general, no material representation of X is such that its physical properties suffice to make it a representation of X as opposed to a representation of a
representation of X.

5. Here is the argument:

P1. All thoughts have determinate objects.
P2. No purely material representation has a determinate object.
—–
C. No thought is a purely material representation.

6. Let's consider an objection. "Granted, material representations on their own lack determinate reference, but that can be supplied by bringing in causal relations. Thus what makes a tokening of 'cat' refer to a cat rather than to a word is the fact that there is a causal chain starting with a furry critter and terminating with an utterance of 'cat.'"

But causal connections cannot secure determinacy of reference, as Hilary Putnam appreciates (Renewing Philosophy, Harvard UP, 1992, p. 23):

     One cannot simply say that the word "cat" refers to cats because
     the word is causally connected to cats, for the word "cat," or
     rather my way of using the word "cat," is causally connected to
     many things. It is true that I wouldn't be using "cat" as I do if
     many other things were different. My present use of the word "cat"
     has a great many causes, not just one. The use of the word "cat" is
     causally connected to cats, but it is also causally connected to
   &#0
160; the behavior of Anglo-Saxon tribes, for example. Just mentioning
     "causal connection" does not explain how one thing can be a
     representation of another thing, as Kant was already aware.

Searle, Subjectivity, and Objectivity

John Searle is a marvellous critic of theories in the philosophy of mind, perhaps the best. He makes all sorts of excellent points in his muscular and surly way. But his positive doctrine eludes me, assuming it is supposed to be a coherent doctrine. The problem may reside with me, of course. But I am not ready to give up.

So I take yet another stab at making sense of Searle. (The exegetical equivalent of squaring the circle?) His aim is to find a via media between the Scylla of dualism and the Charybdis of materialism. Dualism, whether a dualism of (kinds of) substances or a dualism of (kinds of) properties, makes of mind something mysterious and supernatural and therefore intolerable to naturalists. But materialism, as Searle understands it, issues in the conclusion that "there really isn't such a thing as as consciousness with a first-person, subjective ontology." (Mind, Language, and Society, Basic Books, 1998, p. 45)

What Searle wants to say is that there can be a natural science of consciousness, but one that does not end up by denying its existence, a natural science that is adequate to consciousness in its very subjectivity. But (1) science is objective: it aims at an underlying reality 'beneath' subjective appearances. (2) Consciousness, however, is essentially subjective. It seems, therefore, that (3) there can be no natural science of consciousness.

To defeat this argument, Searle makes a distinction between epistemic subjectivity and ontological subjectivity, and a distinction between epistemic objectivity and ontological objectivity. Compare a pain and a mountain. A pain has a subjective mode of existence whereas a mountain has an objective mode of existence. The difference is that the appearing of the pain is identical to the being of the pain unlike the mountain whose appearing and being are distinct. A pain cannot exist unless it is experienced, whereas a mountain can exist without being experienced. So far, so good. But then Searle maintains that what is ontologically subjective can be studied by a science that is epistemically objective. If this is right, then the argument above falls victim to a failure to distinguish the two senses of 'subjectivity' and the two senses of 'objectivity.' Here is the argument again:

1. Science is objective: it aims at an underlying reality 'beneath' subjective appearances.
2. Consciousness is essentially subjective.
Therefore
3. There can be no natural science of consciousness.

Searle's contention is that there is nothing to prevent a science that is epistemically objective from studying consciousness which is ontologically subjective. Here is the crucial passage (ML&S, pp. 44-45):

     The pain in my toe is ontologically subjective, but the statement
     "JRS now has a pain in his toe" is not epistemically subjective. It
     is a simple matter of (epistemically) objective fact, not a matter
     of (epistemically) subjective opinion. So the fact that
     consciousness has a subjective mode of existence does not prevent
     us from having an objective science of consciousness.

Searle's argument goes like this:

   4. The pain in JRS's toe is ontologically subjective.
   5. That JRS has a pain in his toe is a matter of epistemically
   objective fact.
   Therefore
   6. That consciousness has a subjective mode of existence is consistent
   with there being an epistemically objective science of it.

Although both premises are true, the conclusion does not follow from them. Searle is confusing the objective reality of his pain with its objective accessibility to science. This confusion is aided and
abetted by the ambiguity of 'object' and 'objective.' From the fact that the pain exists in itself and is in that sense objective, it does not follow that the pain is exhaustively knowable by science, that it
is an object of scientific knowledge.

Consider a different example. Mary says, "The room is cold!" Bill says, "The room is not cold." Clearly, there is no fact of the matter as to whether or not the room is cold or the opposite. It is a matter of perception: Mary feels cold, while hot-blooded Bill does not. The objective fact is that the room temperature is 68 degrees Fahrenheit, a fact perceived differently by Bill and Mary.

Note that it is also an objective fact that Mary feels cold and that Bill does not. But how is it supposed to follow that Bill's sensation, or Mary's, are exhaustively understandable in natural-scientific terms? The fact that the sensations themselves exist in reality and not relative to perceivers does not show that they are wholly accessible to science. It is precisely their "first-person ontology" that keeps them from being wholly accessible to science.

The mistake Searle is making is to think that what is objectively real (in the sense of that which exists in itself and not relative to perceivers) is exhausted by what is natural and therefore accessible to natural science. He mistakenly identifies reality with nature. It is undoubtedly true that sensations (and mental data generally) exist in observer-independent fashion: they are not mere appearances but appearances in which appearance and reality coincide. Thus Searle is right to say that they are ontologically subjective. Searle is also right to say that this ontological subjectivity is consistent with mental data's existing in themselves and not merely for an observer.

But as far as I can see it is a howling non sequitur to conclude that mental data are objects of scientific knowledge. To be objectively real (in the sense of existing an sich and not merely for observers) is not the same as being an object of scientific knowledge. Beware the ambiguity of 'object'! It appears that Searle has fallen victim to it.

But why does Searle mistakenly identify reality with the objects of scientific knowledge — especially given his clear insight into the ontological subjectivity of mental data? Because he is in the grip of
the IDEOLOGY of scientific naturalism. This prevents him from properly exploiting his insight. But to make this allegation stick will require further citations and considerations.

My Searle posts are in the aptly-named Searle category.

Could Intentionality be an Illusion? A Note on Rosenberg

Could intentonality be an illusion? Of course not. But seemingly intelligent people think otherwise:

A single still photograph doesn't convey movement the way a motion picture does. Watching a sequence of slightly different photos one photo per hour, or per minute, or even one every 6 seconds won't do it either. But looking at the right sequence of still pictures succeeding each other every one-twentieth of a second produces the illusion that the images in each still photo are moving. Increasing the rate enhances the illusion, though beyond a certain rate the illusion gets no better for creatures like us. But it's still an illusion. There is noting to it but the succession of still pictures. That's how movies perpetrate their illusion. The large set of still pictures is organized together in a way that produces in creatures like us the illusion that the images are moving. In creatures with different brains and eyes, ones that work faster, the trick might not work. In ones that work slower, changing the still pictures at the rate of one every hour (as in time-lapse photography) could work. But there is no movement of any of the images in any of the pictures, nor does anything move from one photo onto the next. Of course, the projector is moving, and the photons are moving, and the actors were moving. But all the movement that the movie watcher detects is in the eye of the beholder. That is why the movement is illusory.

The notion that thoughts are about stuff is illusory in roughly the same way. Think of each input/output neural circuit as a single still photo. Now, put together a huge number of input/output circuits in the right way. None of them is about anything; each is just an input/output circuit firing or not. But when they act together, they "project" the illusion that there are thoughts about stuff. They do that through the behavior and the conscious experience (if any) that they produce. (Alex Rosenberg, The Atheists' Guide to Reality: Enjoying Life Without Illusions. The quotation was copied from here.)

Rosenberg is not saying, as an emergentist might, that the synergy of sufficiently many neural circuits gives rise to genuine object-directed thoughts. He is saying something far worse, something literally nonsensical, namely, that the object-directed thought that thoughts are object-directed is an illusion. The absurdity of Rosenberg's position can be seen as follows.

1. Either the words "The notion that thoughts are about stuff is illusory" express a thought — the thought that there are no object-directed thoughts — or they do not.
2. If the latter, then the words are meaningless.
3. If the former, then the thought is either true or false.
4. If the thought is true, then there there are no object-directed thoughts, including the one expressed by Rosenberg's words, and so his words are once again meaningless.
5. If the thought is false, then there are object-directed thoughts, and Rosenberg's claim is false.
Therefore
6. Rosenberg's claim is either meaningless or false. His position is self-refuting.

As for the analogy, it is perfectly hopeless, presupposing as it does genuine intrinsic intentionality. If I am watching a movie of a man running, then I am under an illusion in that there is nothing moving on the movie screen: there is just a series of stills. But the experience I am undergoing is a perfectly good experience that exhibits genuine intrinsic intentionality: it is a visual experiencing of a man running, or to be perfectly punctilious about it: a visual experiencing AS OF a man running. Whether or not the man depicted exists, as would be the case if the movie were a newsreel, the experience exists, and so cannot be illusory.

To understand the analogy one must understand that there are intentional experiences, experiences that take an accusative. But if you understand that, then you ought to be able to understand that the analogy cannot be used to render intelligible how it might that it is illusory that there are intentional experiences.

What alone remains of interest here is how a seemingly intelligent fellow could adopt a position so manifestly absurd. I suspect the answer is that he has stupefied himself by his blind adherence to scientistic/naturalistic ideology.

Here is an earlier slap at Rosenberg. Peter Lupu joins in the fun here.

Telescope and ‘Cerebroscope’

If God cannot appear through a telescope, why do you think that mind can appear through a 'cerebroscope'?

Memory, Memory Traces, and Causation

Passing a lady in the supermarket I catch a whiff of patchouli. Her scent puts me in mind of hippy-trippy Pamela from the summer of '69. An olfactory stimulus in the present causes a memory, also in the present, of an event long past, a tête-à-tête with a certain girl. How ordinary, but how strange! Suddenly I am 'brought back' to the fantastic and far-off summer of '69. Ah yes! What is memory and how does it work? How is it even possible?

Let's start with the 'datanic' as I like to say:

1. There are (veridical) memories through which we gain epistemic access to the actual past, to events that really happened. The above example is a case of episodic personal memory. I remember an event in my personal past. To be precise, I remember my having experienced an event in my personal past. My having been born by Caesarean section is also an episode from my personal past, and I remember that that was my mode of exiting my mother's body; but I don't remember experiencing that transition. So not every autobiographical memory is a personal episodic memory. The latter is the only sort of memory I will be discussing in this post. The sentence in boldface is the nonnegotiable starting point of our investigation.

We now add a couple of more theoretical and less datanic propositions, ones which are not obvious, but are plausible and accepted by many theorists:

2. Memory is a causal notion. A mental image of a past event needn't be a memory of a past event. So what makes a mental image of a past event a memory image? Its causal history. My present memory has a causal history that begins with the event in 1969 as I experienced it.

3. There is no action at a temporal distance. There is no direct causation over a temporal gap. There are no remote causes; every cause is a proximate cause. A necessary ingredient of causation is spatiotemporal contiguity. So while memory is a causal notion, my present memory of the '69 event is not directly caused by that event. For how could an event that no longer exists directly cause, over a decades-long temporal gap, a memory event in the present? That would seem to be something 'spooky,' a kind of magic.

Each of these propositions lays strong claim to our acceptance. But how can they all be true? (1) and (2) taken together appear to entail the negation of (3). How then can we accommodate them all?

Memory trace theories provide a means of accommodation. Suppose there are memory traces or engrams engraved in some medium. For materialists this medium will have to be the brain. One way to think of a memory trace is as a brain modification that was caused at the time of the original experience, and that persists since that time. So the encounter with Pam in '69 induced a change in my brain, left a trace there, a trace which has persisted since then. When I passed the patchouli lady in the supermarket, the olfactory stimulus 'activated' the dormant memory trace. This activation of the memory trace either is or causes the memory experience whose intentional object is the past event. With the help of memory traces we get causation wthout action at a temporal distance.

(Far out, man!)

The theory or theory-schema just outlined seems to allow us to uphold each of the above propositions. In particular, it seems to allow us to explain how a present memory of a past event can be caused by the past event without the past event having to jump the decades-long temporal gap between event remembered and memory. The memory trace laid down in '69 by the original experience exists in the present and is activated in the present by the sensory stimulus. Thus the temporal contiguity requirement is satisfied. And if the medium in which the memory traces are stored is the brain or central nervous system, then the spatial contiguity requirement is also satisfied.

Question: Could memory traces play merely causal roles?

Given (2) and (3), it seems that memory traces must be introduced as causal mediators between past and present. But could they be just that? Or must they also play a representational role? Intuitively, it seems that nothing could be a memory trace unless it somehow represented the event of which it is a trace. If E isthe original experience, and T is E's trace, then it it seems we must say that T is of E in a two-fold sense corresponding to the difference between the subjective and objective genitive. First, T is of E in that T is E's trace, the one that E caused. Second, T is of E in that T represents E.

It seems obvious that a trace must represent. In my example,the sensory stimulus (the whiff of patchouli) is not of or about the '69 event. It merely activates the trace, rendering the dispositional occurrent. But the memory is about the '69 event. So the aboutness must reside in the trace. The trace must represent the event that caused it – and no other past event. The memory represents because the trace represents. If the trace didn't represent anything, how could the memory — which is merely the activation of the trace or an immediate causal consequence of the activation of the trace — represent anything? How a persisting brain modification — however it is conceived, whether it is static or dynamic, whether localized or nonlocalized — can represent anything is an important and vexing question but one I will discuss in a later post.

Right now I want to nail down the claim that memory traces cannot play a merely causal role, but must also bear the burden of representation.

Suppose a number of strangers visit me briefly. I want to remember them, but my power of memory is very weak and I know I will not remember them without the aid of some mnemonic device. So I have my visitors leave calling cards. They do so, except that they are all the same, and all blank (white). These blank cards are their traces, one per visitor. The visitors leave, but the cards remain behind as traces of their visit. I store the cards in a drawer. I 'activate' a card by pulling it out of storage and looking at it. I am then reminded (at most) that I had a visitor, but not put in mind of any particular visitor such as Tom. So even if the card in my hand was produced by Tom, that card is useless for the purpose of remembering Tom. Likewise for every other card. Each was produced by someone in particular and only by that person; but none of them 'bring back' any particular person.

Bear in my mind that I don't directly remember any of my visitors. My only memory access to them is via their traces, their calling cards. For the visitors are long gone just like the '69 experience. So the problem is not merely that I don't know which card is from which person; the problem is that I cannot even distinguish the persons.

Had each visitor left a differently colored card, that would not have helped. Nor are matters helped if each visitor leaves a different sort of trace; a bottle cap, a spark plug, a lock of hair, a guitar pick. Even if Tom is a guitar player and leaves a guitar pick, that is unhelpful too since I have no access to Tom except via his trace.

So it doesn't matter whether my ten visitors leave ten tokens of the same type, or ten tokens each of a different type. Either way I won't be able to remember them via the traces they leave behind. Clearly, what I need from each visitor is an item that uniquely represents him or her — as opposed to an item that is merely caused to be in my house by the visitor. Suppose Tom left a unique guitar pick, the only one of its kind in existence. That wouldn't help either since no inspection of that unique pick could reveal that it was of Tom rather than of Eric or Eric's cat. Ditto if Tom has signed his card or his pick 'Tom Riff.' That might be a phony name, or the name of him and his guitar — doesn't B. B . King call his guitar 'Lucille'?

If I can remember that it was Tom who left the guitar pick, then of course I don't need the guitar pick to remember Tom by. I simply remember Tom directly without the need for a trace. On the other hand, if I do need a trace in order to remember long gone Tom, then that trace must have representational power: it cannot be merely something that plays a causal role.

Traces theories have to avoid both circularity and vicious infinite regress.

Circularity. To explain the phenomenon of memory, the trace theory posits the existence of memory traces. But if the explanation in terms of traces ends up presupposing memory, then the theory is circular and worthless. If what makes the guitar pick a trace of Tom is that I remember that Tom left it, then the explanation is circular. Now consider the trace T in my brain which, when activated by stimulus S causes a memory M of past experience E. M represents E because T represents E. What makes T represent E? What makes the memory trace caused by the encounter with Pam in '69 represent Pam or my talking with her? The answer cannot be that I remember the memory trace being caused by the encounter with Pam. For that would be blatantly circular. Besides, memory traces in the brain are not accessible to introspection.

Infinite Regress. Our question is: what makes T represent E and nothing else? To avoid circularity one might say this: There is a trace T* which records the fact of E's production of T, and T represents E in virtue of T*. But this leads to a vicious infinite regress. Suppose Sally leaves a photo of herself. How do I know that the photo is of Sally and not of her sister Ally? If you say that I directly remember Sally and thereby know that the photo is unambiguously of her, then you move in a circle. You may as well just say that we remember directly and not via traces. So, to hold onto the trace theory, one might say the following: There is a photo of Sally and her photograph, side by side. Inspection of this photo reveals that that the first photo is of Sally. But this leads to regress: what makes the second photo a photo of the first?

Conclusion: To avoid both circularity and infinite regress, memory traces must possess intrinsic representational power. Their role cannot be merely causal.

A later post will then address the question whether memory traces could have intrinsic representational power. If you are a regular reader of this blog you will be able to guess my answer.

REFERENCE: John Heil, "Traces of Things Past," Philosophy of Science, vol. 45, no. 1 (March 1978), pp. 60-72. My calling card example above is a reworking of Heil's tennis ball example.

Intentionality Not a ‘Hard Problem’ for Physicalists?

The qualia-based objections are supposed to pose a 'hard' problem for defenders of physicalism. The implication is that the problems posed by intentionality are, if not exactly 'easy,' then at least tractable. An earlier post discussed a version of the knowledge argument, which is one of the qualia-based objections. (Two others are the absent qualia argument and the zombie argument.) It seems to me, though, that intentionality is also a damned hard problem for physicalists to solve, so hard in fact as to be insoluble within physicalist constraints and another excellent reason to reject physicalism.

Before proceeding I want to make two preliminary points.

The first is that the untenability of physicalism does not entail the acceptability of substance dualism. Contrapositively, the unacceptability of substance dualism does not entail the tenability of physicalism. So if a physicalist wishes to point out the problems with substance dualism, he is free to do so. But he ought not think that such problems supply compelling reasons to be a physicalist. For it is obvious that the positions stand to each other as logical contraries; hence both could be be false.

My second point is that considerations of parsimony do favor physicalism over dualistic schemes — but only on condition that the relevant data can be adequately accounted for. And that is one big 'only if.' (See The Use and Abuse of Occam's Razor: On Multiplying Entities Beyond Necessity.)

An Argument Sketched. Mary, Meet Marty.

We were talking about Frank Jackson's Mary. Now I introduce Marty, a Martian scientist who like Mary knows everything there is to know about human brains and their supporting systems. So he knows all about what goes in the human brain and CNS when we humans suffer and enjoy twinges and tingles, smells and stinks, sights and sounds, etc. We will suppose that Marty's sensorium is very different, perhaps totally different than ours. He may have infrared color qualia but no color qualia corresponding to the portion of the EM spectrum for which we have color qualia. Marty also knows everything there is to know about what goes on in my head when I think about various things. We may even suppose that Marty is studying me right now with his super-sophisticated instruments and knows exactly what is going on in my head right now when I am in various intentional states.

Suppose I am now thinking about dogs. I needn't be thinking about any particular dog; I might just be thinking about getting a dog, which of course does not entail that there is some particular dog, Kramer say, that I am thinking about getting. Indeed, one can think about getting a dog that is distinct from every dog presently in existence! How? By thinking about having a dog breeder do his thing. If a woman tells her husband that she wants a baby, more likely than not, she is not telling him that she wants to kidnap or adopt some existing baby, but that she wants the two of them to engage in the sorts of conjugal activities that can be expected to cause a baby to exist. Same with me. I can want a dog or a cat or a sloop or a matter transmitter even if the object of my wanting does not presently exist.

So right now I am thinking about a dog, but no presently existing dog. My thinking has intentional content. It is an instance of what philosophers call intentionality. My act of thinking takes an object, or has an accusative. It exhibits aboutness or of-ness in the way a pain quale does not exhibit aboutness of of-ness. It is important to realize that my thinking is intrinsically such as to be about a dog: the aboutness is not parasitic upon an external relation to an actual dog. That is why I rigged the example the way I did. My thinking is object-directed despite there being no object in existence to which I am externally related. This blocks attempts to explain intentionality in terms of causation. Such attempts fail in any case. See my post on Representation and Causation.

The question is whether the Martian scientist can determine what that intentional content is by monitoring my neural states during the period of time I am thinking about a dog. The content before my mind has various subcontents: hairy critter, mammal, barking animal, man's best friend . . . . But none of this content will be discernible to the Martian neuroscientist on the basis of complete knowledge of my neural states, their relations to each other and to sensory input and behavioral output. To strengthen the argument we may stipulate that Marty lacks the very concept dog. Therefore, there is more to the mind than what can be known by even a completed neuroscience. Physicalism (materialism) is false.

The argument is this:

1. Marty knows all the physical and functional facts about my body and brain during the time I am thinking about a dog.
2. That I am thinking about a dog is a fact.
3. Marty does not know that I am thinking about a dog.
Therefore
4. Marty does not know all the facts about me and my mental activity.
Therefore
5. There are mental facts that are not physical or functional facts, and physicalism is false.

Credit where credit is due: The above is my take on a more detailed and careful argument presented here by Laurence BonJour. Good day!

On Paul Churchland’s ‘Refutation’ of the Knowledge Argument

If this post needs theme music, I suggest Party Lights (1962) by the one-hit wonder, Claudine Clark: "I see the lights/I see the party lights/They're red and blue and green/Everybody in the crowd is there/But you won't let me make the scene!" (Because, mama dear, you've kept me cooped up in a black-and-white room studying neuroscience.)

…………………………..

The 'Knowledge Argument' as it is known in the trade has convinced many of the untenability of functionalism in the philosophy of mind. Here is Paul M. Churchland's presentation of Frank Jackson's version of the argument:

1. Mary knows everything there is to know about brain states and their properties.
2. It is not the case that Mary knows everything there is to know about sensations and their properties.
Therefore, by Leibniz's law [i.e., the Indiscernibility of Identicals; see my post 'Leibniz's Law': A Useless Expression],
3. Sensations and their properties are not identical to brain states and their properties.

("Reduction, Qualia, and the Direct Introspection of the Brain," Journal of Philosophy, vol. 82, no. 1, January 1985, pp. 8-28, sec. IV, "Jackson's Knowledge Argument.")

Mary is a brilliant neuroscientist who has spent her entire life in a visually impoverished state. Pent up in a room from birth and sheltered from colors, her visual experience is restricted to black and white and shades of gray. You are to imagine that she has come to know everything there is to know about the brain and its visual system. Her access to the outer world is via black-and-white TV. The neuroscience texts over which she so assiduously pores have beeen expurgated by the dreaded Color Censor.

Churchland finds two "shortcomings" with the above argument. I will discuss only the first in this post.

Churchland smells a fallacy of equivocation. 'Knows about,' he claims, is being used in different senses in (1) and (2):

Knowledge in (1) seems to be a matter of having mastered a set of sentences or propositions, the kind one finds written in neuroscience texts, whereas knowledge in (2) seems to be a matter of having a representation of redness in some prelingusitic or sublinguistic medium of representation for sensory variables, or to be a matter of being able to make certain sensory discriminations, or something along these lines. (Emphasis in original)

Rather than argue that that there is no equivocation in the argument as Churchland formulates it, I think it is best to concede the point, urging instead that Chuchland has not presented the Knowledge Argument fairly. He finds an equivocation only because he has set up a straw man. Consider the following version:

4. Mary knows all of the of the physical facts about color vision.
5. Venturing outside her black-and-white domain for the first time, she comes to know a new fact: what it is like to see red.
Therefore
6. This new fact is not a physical fact.

There is no equivocation on 'knows' in this argument. Mary knows all of the physical facts about the brain and the visual system. If the physical facts are all the facts, then, when she emerges from the room and views a red sunset, she learns nothing new. But this is not the case. She does learn something new, something she might express by exclaiming, "So this is what it is like to see red!" That is a new fact that she comes to know.

The best counter to this argument is to deny (2) by arguing that that no new fact is learned when Mary steps outside. Mary simply acquires a new concept, a new way of gaining epistemic access to the same old physical facts, namely, the physical and functional facts involved in seeing a red thing. As Churchland puts it,

. . . the difference between a person who knows all about the visual cortex but has never enjoyed a sensation of red, and a person who knows no neuroscience but knows well the sensation of red, may reside not in what is respectively known by each (brain states by the former, qualia by the latter), but rather in the different type of knowledge each has of exactly the same thing. The difference is in the manner of the knowing, not in the nature(s) of the thing known. (Emphases in original)

Churchland's suggestion is that one and the same physical reality appears, or can appear, in two different ways, a third-person way and a first-person way, and that this first-person way of access is no evidence of a first-person way of being. The sensory quale is not an item distinct from the underlying state of the brain, an item that escapes the physicalist's net; the quale is a mode of presentation of the brain state. The quale is an appearance of the brain state. And so Churchland thinks that one can have knowledge of one's sensations via their qualitative features without knowing any neuroscience without it being the case that "sensations are beyond the reach of physical science."

In sum, sensations are identical to brain states. But they can be accessed in two ways, via qualia, and via neuroscience. That there are two different modes of epistemic access does not entail that qualia are distinct in reality from brain states. One and the same btrain "uses more modes and media or representation than the simple stoarge of sentences."

Critique

Unfortunately, there is no clear sense in which a quale is an appearance of a brain state. The former may be caused by the latter. But that is not to say that the quale is of or about the brain state. Phenomenal redness does not present a brain state to me. It does not present anything (distinct from itself) to me. After all, qualia are non-intentional: they lack aboutness. No doubt a quale has a certain content, but not an intentional or representational content. One can describe it without describing what it is of, for the simple reason that there is nothing it is of. An intentional state, however, cannot be described without describing what it is of. I can't desire without desiring something, a cold beer, say. So 'cold beer' enters, and enters necessarily, into the description of the mental state I am in when I desire a cold beer. But no words referring to neural items need enter into the description of what I experience when I experience a yellowish-orange afterimage, or feel anxious.

Qualia do not play a merely epistemic role as Churchland thinks. They are items in their own right. They are not mere appearances of an underlying reality; they are items with their own mode of being. For a quale, to be is to be perceived. Its reality consists in its appearing. For this reason it makes no sense to say that the reality of a quale is something distinct from it, something physical to which the quale refers.

Suppose someone, armed with the Indiscernibility of Identicals, were to argue that the Morning Star and the Evening Star are numerically distinct because they differ property-wise, the one, but not the other, being the brightest celestial object in the morning sky. Such an argument could be easily rebutted by pointing out that the two 'stars' are merely different modes of presentation of one and the same physical thing, the planet Venus. Difference in epistemic access does not argue difference in being! Churchland thinks he can similarly rebut the person who argues that qualia are distinct from brain states by claiming that qualia and sentences of neuroscience are different modes of presentation or "media of representation" of one and the same thing, which is wholly physical.

But here is precisely where the mistake is made. Qualia do not present or represent anything. In particular, they do not represent their causes. They are items in their own right with their own mode of being, a mode of being distinct from the mode of being of physical items. For a quale, to be is to be perceived. For a physical item, this is not the case. One cannot drive a wedge between the appearance and the reality of a quale; but one can and must drive such a wedge between the appearance and the reality of physical items.

Even if one were to insist that qualia present or represent their underlying brain states, the materialist position would still be absurd. For if x represents y, then x is distinct from y — in reality and not merely for us. So if phenomenal redness is an appearance of a complex brain state, the two items are distinct. Churchland thinks he can place qualia on the side of representation and then forget about them. But that is an obvious mistake.

Underlying this obvious mistake is the fundamental absurdity of materialism, which is the attempt to understand mind in wholly non-mental terms. It cannot be done since the very investigation of physical reality presupposes mind.

Against Functionalism in the Philosophy of Mind: Argument One

In my last philosophy of mind post on property dualism I posed a problem:

My problem, roughly, is that I don't understand how a physical particular (a brain, a region of a brain, a brain event, or state, or process) can instantiate one or more irreducibly mental properties. Why should there be a problem? Well, if a physical particular is exhaustively understandable in terms of physics (and the sciences based on it) then there is just nothing irreducibly mental about it, in which case it cannot instantiate an irreducibly mental property.

At the end of that post I provided an answer to that question:

Mental properties are functional properties. So when we say that x, a brain event say, has a mental property, all we mean is that it stands in certain causal relations to sensory inputs, behavioral outputs, and intervening brain events. So what makes the brain event mental is simply the relations in which it stands to inputs, outputs and other brain events. Once you grasp this, then you grasp that the brain event can be wholly physical in nature despite its having a mental property. Mental properties are not intrinsic but relational.

The answer, in short, is that mental properties are not intrinsic properties. But then I wrote,

Unfortunately, this won't do. Felt sadness has an intrinsically mental nature that cannot be functionally characterized. A subsequent post will spell this out in detail.

This is the subsequent post.

Suppose Socrates Jones is in some such state as that of perceiving a tree. The state is classifiable as mental as opposed to a physical state like that of his lying beneath a tree. What makes a mental state
mental? That is the question.

The functionalist answer is that what makes a mental state mental is just the causal role it plays in mediating between the sensory inputs, behavioral outputs, and other internal states of the subject in question. The idea is not the banality that mental states typically (or even always) have causes and effects, but that it is causal role occupancy, nothing more and nothing less, that constitutes the
mentality of a mental state. The intrinsic nature of what plays the role is relevant only to its fitness for instantiating mental causal roles, but not at all relevant to its being a mental state.

Consider a piston in an engine. You can't make a piston out of chewing gum, but being made of steel is no part of what makes a piston a piston. A piston is what it does within the 'economy' of the engine. Similarly, on functionalism, a mental state is what it does. This allows, but does not entail, that a mental state be a brain or CNS state. It also allows, but does not entail, that a mental state be a state of a computing machine.

To illustrate, suppose my cat Zeno and I are startled out of our respective reveries by a loud noise at time t. Given the differences between human and feline brains, presumably man and cat are not in type-identical brain states at t. (One of the motivations for functionalism was the breakdown of the old type-type identity theory of Herbert Feigl, U. T. Place. J. J. C. Smart, et al.) Yet both man and cat are startled: both are in some sense in the same mental state, even though the states they are in are neither token- nor type-identical. The functionalist will hold that we are in functionally the same mental state in virtue of the fact that Zeno's brain state plays the same role in him as my brain state plays in me. It does the same mediatorial job vis-a-vis sensory inputs, other internal states, and behavioral outputs in me as the cat's brain state does in him.

On functionalism, then, the mentality of the mental is wholly relational. And as David Armstrong points out, "If the essence of the mental is purely relational, purely a matter of what causal role is played, then the logical possibility remains that whatever in fact plays the causal role is not material." This implies that "Mental states might be states of a spiritual substance." Thus the very feature of functionalism that allows mentality to be realized in computers and nonhuman brains generally, also allows it to be realized in spiritual substances if there are any.

Whether this latitudinarianism is thought to be good or bad, functionalism is a monumentally implausible theory of mind. There are the technical objections that have spawned a pelagic literature: absent qualia, inverted qualia, the 'Chinese nation,' etc. Thrusting these aside, I go for the throat, Searle-style.

Functionalism is threatened by a fundamental incoherence. The theory states that what makes a state mental is nothing intrinsic to the state, but purely relational: a matter of its causes and effects. In us, these happen to be neural. (I am assuming physicalism for the time being.) Now every mental state is a neural state, but not every neural state is a mental state. So the distinction between mental and nonmental neural states must be accounted for in terms of a distinction between two different sets of causes and effects, those that contribute to mentality and those that do not. But how make this distinction? How do the causes/effects of mental neural events differ from the causes/effects of nonmental neural events? Equivalently, how do psychologically salient input/output events differ from those that lack such salience?

Suppose the display on my monitor is too bright for comfort and I decide to do something about it. Why is it that photons entering my retina are psychologically salient inputs but those striking the back of my head are not? Why is it that the moving of my hand to to adjust the brightness and contrast controls is a salient output event, while unnoticed perspiration is not?

One may be tempted to say that the psychologically salient inputs are those that contribute to the production of the uncomfortable glare sensation, and the psychologically salient outputs are those that manifest the concomitant intention to make an adjustment. But then the salient input/output events are being picked out by reference to mental events taken precisely NOT as causal role occupants, but as exhibiting intrinsic features that are neither causal nor neural: the glare quale has an intrinsic nature that cannot be resolved into relations to other items, and cannot be identified with any brain state. The functionalist would then be invoking the very thing he is at pains to deny, namely, mental events as having more than neural and causal features.

Clearly, one moves in a circle of embarrassingly short diameter if one says: (i) mental events are mental because of the mental causal roles they play; and (ii) mental causal roles are those whose occupants are mental events.

The failure of functionalism is particularly evident in the case of qualia. Examples of qualia: felt pain, a twinge of nostalgia, the smell of burnt garlic, the taste of avocado. Is it plausible to say that such qualia can be exhaustively factored into a neural component and a causal/functional component? It is the exact opposite of plausible. It is not as loony as the eliminativist denial of quali, but it is close. The intrinsic nature of qualitative mental states is essential to them. It is that intrinsic qualitative nature that dooms functionalism.

I conclude that if the only way to render property dualism coherent is by construing mental properties as functional properties, then property dualism is untenable.

Property Dualism and Supervenience

A reader asked why I didn't mention supervenience in my recent posts on property dualism. He opines that "the notion was invented to make sense of the position you are arguing against." Let's see.

My Problem With Property Dualism Roughly Stated

I take a property dualist to be one who maintains all of the following propositions:

1. There are irreducibly mental properties.
2. There are irreducibly physical properties.
3. All particulars are physical particulars.
4. Some but not all particulars instantiate both irreducibly mental and irreducibly physical properties.

My problem, roughly, is that I don't understand how a physical particular (a brain, a region of a brain, a brain event, or state, or process) can instantiate one or more irreducibly mental properties. Why should there be a problem? Well, if a physical particular is exhaustively understandable in terms of physics (and the sciences based on it) then there is just nothing irreducibly mental about it, in which case it cannot instantiate an irreducibly mental property. I am making the following assumption:

A. If a nonrelational predicate P is true of a particular x, then there must be something in or about x that grounds P's applicability to x.

So if 'feels pain' is true of a physical particular, and 'feels pain' picks out an irreducibly mental property, then there must be something irreducibly mental about that physical particular. Otherwise there would be nothing in or about the particular that could render the predicate true of the particular. But if there is something irreducibly mental about a physical particular, then that particular is not physical in the sense of being exhaustively understandable in terms of physics.

I find (A) to be self-evident. For suppose you were to deny it. Then you would be countenancing the following: there is some particular x that instantiates a property P-ness even though the nature of x excludes P-ness. You would be countenancing, for example, an electron (which is course a negatively charged particle) which yet instantiates the property of being positively charged. If a particular has a an intrinsic (non-relational) property, then that property expresses what the particular is, its nature (in a broad sense of this term).

Now we have to see whether the notion of supervenience can help me with my problem.

Strong Supervenience

The problem for the nonreductive physicalist is that he must avoid both eliminativism and reductionism but without falling into epiphenomenalism, emergentism, or (of course) substance dualism. Epiphenomenalism cannot accommodate the fact that mental phenomena sometimes enter into the etiology of physical events, while emergentism and substance dualism leave physicalism behind. The problem is to somehow secure the reality, the causal efficacy, and the irreducibility of the mental while maintaining the dependence of the mental on the physical. Nice work if you can get it! What the physicalist needs, it seems, is a dualism of properties together with the idea that the mental properties somehow nonreductively depend on the physical ones. But how articulate this dependency relation?

Enter supervenience. The basic idea is that mental properties are not identical with, but merely supervene upon, physical properties in the way in which ethical properties have been thought (by G. E. Moore, R. M. Hare, and others) to supervene upon natural properties. Suppose A and B are both ethically good. It does not follow that there is any one natural, non-disjunctive, property with which goodness can be identified. Perhaps A is good in virtue of being brave and trustworthy, whereas B is good in virtue of being temperate and just. Goodness is in this sense "multiply realizable." A and B are both good despite the fact that their goodness is realized by different natural properties.

Nevertheless, (i) a person cannot be good unless there is some natural property in virtue of whose possession he is good, and (ii) if a person is good in virtue of possessing certain natural properties, then anyone possessing the same natural properties must also be good. Given that A-properties supervene upon B-properties, the "supervenience T-shirt" might read: "No A-property without a B-property" on the front; "same B-properties, same A-properties" on the back. As Jaegwon Kim puts it, "The core idea of supervenience as a relation between two families of properties is that the supervenient properties are in some sense determined by, or dependent upon, the properties on which they supervene." (Jaegwon Kim, "Epiphenomenal and Supervenient Causation," in Supervenience and Mind: Selected Philosophical Essays, Cambridge University Press, 1995, p. 98.)

Kim's preferred way of cashing this out is in terms of strong supervenience. Let A and B be families of properties closed under such Boolean operations as complementation, conjunction and disjunction. A strongly supervenes on B just in case:

(SS) Necessarily, for any property F in A, if any object x has F, then there exists a property G in B such that x has G, and necessarily anything having G has F.

Applying (SS) to physicalism, we may define the determination thesis of strong supervenience physicalism as the view that, necessarily, (i) for any mental property M, if x has M, then there is physical property P such that x has P, and (ii) necessarily, anything having P has M.

But how does this help me with my problem? If x has M and M is an irreducibly mental property, then, by assumption (A) above, x is at least in part mental, and not wholly physical where 'wholly physical' means 'exhaustively understandable in terms of physics and the sciences based on it.' This problem is not solved by telling me that x cannot have a mental property without having a physical property, and that anything having that physical property must have the mental property. For my problem is precisely how x, which is wholly physical, can have an irreducibly mental property in the first place.

One might respond along the following lines. "Look, the whole idea here is that mental properties are functional properties. So when we say that x, a brain event say, has a mental property, all we mean is that it stands in certain causal relations to sensory inputs, behavioral outputs, and intervening brain events. So what makes the brain event mental is simply the relations in which it stands to inputs, outputs and other brain events. Once you grasp this, then you grasp that the brain event can be wholly physical in nature despite its having a mental property. Mental properties are not intrinsic but relational."

Unfortunately, this won't do. Felt sadness has an intrinsically mental nature that cannot be functionally characterized. A subsequent post will spell this out in detail.

Besides, if the property dualist holds that mental properties are really relational, then, strictly speaking, he is not a property dualist. He is not maintaining that there are two sorts of properties, but that mentality consists of relations and that there are no monadic mental properties. Furthermore, his talk of irreducibility must mean only that that type-type identities fail, that for every mental property there is not one unique physical property with which it is identical. Irreducibility boils down to multiple realizability. Mental 'properties' are irreducible in that they are multiply realizable.

Property Dualism, the Red Ball Analogy, and Emergence

This post advances the discussion in the ComBox attached to Could Brains Have Mental Properties?

It would be very easy to be a property dualist in the philosophy of mind if one were also a substance dualist. What I am having trouble understanding is how a property dualist can be a substance monist. In contemporary discussions, the one category of substances is that of material substances. 'Property dualism,' then, is an abbreviated name for the position in the philosophy of mind according to which mental and physical properties are mutually irreducible — hence the dualism — but had by the only kind of substances there are, material substances. Hence the monism. But having employed the traditional jargon, I'll now drop the irridescent word 'substance' which will undoubtedly cause many to stumble and use 'particular' instead. A particular is an unrepeatable entity. It needn't be a continuant. Events and processes count as particulars.

To come directly to my difficulty. How can an irreducibly mental property be instantiated by a physical particular? An irreducibly mental property is one that is not identical with, or reducible to, any physical property. Examples of mental properties: being in pain; thinking about Thanksgiving dinner; having a blue sensation; wanting a cup of coffee. This post assumes that at least some mental properties are irreducibly mental. Various arguments have been given; this is not the place to rehearse them. An irreducibly physical property is one that is not identical with, or reducible to, any mental property. Examples of physical properties: impedance, ductility, motion, solubility, weighing 10 kg. I will assume that all physical properties are irreducibly physical. (It is not that I rule out idealism; it's that the goddess of blogging reminds me that brevity is the soul of blog.)

To further focus the question we need to exclude relational properties. Weaver's Needle has the property of being thought about by me now. So a physical particular has now an irreducibly mental property. But this is unproblematic because the property in question is relational: it does not affect the Needle in its intrinsic nature. But if my brain is what does the thinking in me, and I am thinking about Weaver's Needle, it is not so easy to understand how my brain, a physical thing, can have the irreducibly mental intrinsic property, thinking about Weaver's Needle. (If you think that is not an intrinsic property, substitute wanting a sloop, given that there is no particular sloop in existence that I want.)

So in what follows by 'irreducibly mental properties' I mean 'irreducibly mental intrinsic properties.'

My question is whether the following tetrad is consistent:

1. There are irreducibly mental properties.
2. There are irreducibly physical properties.
3. All particulars are physical particulars.
4. Some but not all particulars instantiate irreducibly mental and irreducibly physical properties.

You might think there is no problem. Color and shape properties are mutually irreducible. Yet some physical particulars instantiate both color and shape properties. A red ball is both red and spherical despite the mutual irreducibility of redness and sphericity. Imagine that the red ball is red all the way through and not red merely on its surface. This will preempt one from saying that the ball is red in virtue of a proper part of it being red.

So why can't mental and physical properties be had by one and the same physical particular? Doesn't the analogy show that the tetrad is consistent? Mental properties are to physical properties as color properties are to shape properties. Just as one and the same physical particular, a ball say, can be both red and spherical, one and the same particular, a brain (or a portion of a brain or an event or process in a brain) can be both located in a region of space and thinking about Boston or feeling nostalgic.

I will now argue that the analogy is hopeless.

A Point of Disanalogy

Colors and shapes are mutually irreducible, but they are also such that color properties cannot be instantiated without shape properties being instantiated, and vice versa. I am talking about colors and shapes in Sellars' "manifest image," colors and shapes as they appear to normal visual perceivers. No color is a shape; but it is also true that there are no colored particulars without shapes, and no shaped particulars without colors. This is a point of phenomenology. One cannot see a colored particular without seeing something that has some shape or other, and vice versa. (And this is so even if the particular is an after-image.) But only some material things are minds. So we have a disanalogy. Wherever a color property is instantiated, a shape property is instantiated, and wherever a shape property is instantiated, a color property is instantiated. But it is not the case that wherever a physical property is instantiated a mental property instantiated. There are plenty of physical particulars that lack mental features even if it is true that everything with mental features also has physical features. Why the asymmetry? This needs to be explained.

Mental Properties as Emergent Properties

Assuming that all particulars are physical particulars — that there are no unembodied or disembodied or possibly disembodied minds — why do only some particulars have mental properties? Probably the most plausible thing to say is that only some physical systems are sufficiently complex to 'give rise' to mentality. This implies that mental properties are emergent: they are system features that are not reducible to or explicable in terms of the properties of the parts of the system even when their causal interactions are taken into account.

Bear in mind that not every system feature is emergent. Suppose a wall is made of 1000 piled stones and nothing else, each stone weighing one lb. It follows that the system — the wall — weighs 1000 lbs. But the property of weighing 1000 lbs., though a property of the whole and not of any part, is not an emergent property. For it is determined by the properties of the parts. In a more complicated system, the parts causally interact in significant ways. (The stones in the wall interact too, but in insignificant ways.) Think of a wrist watch. The property of showing high noon, though a system property, is not an emergent property because it is determined by the properties and causal interactions of the parts.

An emergent property is one that is irreducible to the properties and causal interactions of the items in its emergence base, but somehow emerges from that emergence base and remains tied to it. The notion of emergence is a curious and possibly incoherent one, combining as it does the notions of irreducibility and dependency. An emergent property is dependent in that (i) it cannot exist uninstantiated, and (ii) it cannot exist unless the emergence base is sufficiently complex, and will continue to exist only as long as the emergence base retains its 'sufficient complexity.' An emergent property is irreducible in that it cannot be accounted for in terms of the properties and interactions of the items in the emergence base. This suggests that emergent properties are real iff they induce causal powers in their possessors above and beyond the causal powers that are explicable in terms of the items in the emergence base.

My point is that if only some physical systems exhibit mentality, namely, those systems that manifest a high degree of (biological) complexity, then the mental properties of these systems must be emergent properties, properties that induce special causal powers in their possessors. But then we must ask what are the possessors of these emergent mental properties. The system as a whole, no doubt. But what does that mean? The mereological sum of the physical items that make up the system in question? But a mereological sum is too frail a reed to support a property. Indeed, some see no real distinction at all between a sum and its members. We need something more substantial to serve as support of mental properties. But I am at a loss to say what that more substantial something is.

The argument so far is as follows. The red ball analogy fails because only some physical particulars instantiate irreducibly mental properties. This is readily explainable if irreducibly mental properties are emergent properties. Emergent properties are system properties, properties of complex (biological) systems. But then the question arises as to what these emergent properties are properties of. They can't be properties of the parts of a system taken distributively any more than the property of weighing 1000 lbs. can be taken to be a property of the stones composing a wall taken distributively. So emergent properties are properties of wholes or collections of some sort. But this seems problematic.

For one thing, there are many mental properties had by one minded organism. I see a javelina; I hear it; I smell it. All in the unity of one consciousness. The mental properties are not just instantiated; they are co-instantiated, instantiated in or by one thing. If Manny sees, Moe hears, and Jack smells, it does not follow that there is one minded organism that does all three. So if mental properties are emergent system properties we need to know which one item it is that instantiates them and unifies them. The brain as a whole? What does that mean? No matter how we construe wholes, whether as mereological sums, mathematical sets ordered or unordered, aggregates, what-have-you, no whole is 'substantiatial' enough to unify the various mental properties that minded organisms exhibit.

It is also unclear how a mere collection could be the subject of experience. The subject of experience is not merely the support and unifier of mental properties; it is also that which is aware (whether intentionally or non-intentionally) in virtue of the instantiation of the mental propertiers. How could the subject of experience be a collection of objects?

So I remain in the dark as to what exactly property dualism could be if it is supposed to be a coherent position. What is it exactly that instantiates mental properties on this view?

Category: Mind