Category: Mind
Galen Strawson on Zombies and Whether ‘Physical’ is a Natural Kind Term
1. What is a zombie?
You will have gathered that a zombie is a creature of philosophical fiction conjured up to render graphic a philosophical issue and to throw certain questions in the philosophy of mind into relief. A zombie is a living being that is physically and behaviorally exactly like a living human being except that it lacks (phenomenal) consciousness. Cut a zombie open, and you find exactly what you would find were you to cut a human being open. And in terms of linguistic and nonlinguistic behavior, there is no way to tell a human being from a zombie. (So don't think of something sleepy, or drugged, or comatose or Halloweenish.) When a zombie sees a tree, what is going on in the zombie's brain is a 'visual' computational process, but the zombie lacks what a French philosopher would call interiority. There is no irreducible subjectivity, no qualitative feel to the 'visual' processing; there is nothing it is like for a zombie to see a female zombie or to desire her. (What's it like to be a horny zombie? There is nothing it is like to be a horny zombie. Indeed, there is nothing it is like to be a zombie, period.)
2. Where do zombies come from?
Zombies surface within the context of discussions of physicalism. Physicalism is an ontological doctrine, a doctrine about what ultimately exists, what exists in the most fundamental sense of 'exists.' The physicalist is committed to the proposition that everything, or at least everything concrete, is either physical or determined by the physical. To be a bit more precise, physicalism is usefully viewed as the conjunction of an 'inventory thesis' which specifies physicalistically admissible individuals and a 'determination thesis' which specifies physicalistically admissible properties. What the inventory thesis says, at a first approximation, is that every concretum is either a physical item or composed of physical items. As for the determination thesis, what it says is that physical property-instantiations determine all other property-instantiations; equivalently, every nonphysical property-instantiation supervenes on physical property-instantiations. This implies that all mental facts supervene upon physical facts. So if a being is conscious, then this fact about it supervenes upon, is determined by, its physical properties. This implies that there cannot be two beings, indiscernible with respect to all physical properties, such that the one is conscious while the other is not. This in turn rules out the possibility of zombies. For, if physicalism is true, once the physical properties are fixed, the mental properties are also automatically fixed.
3. What useful work do zombies do?
If zombies are metaphysically (broadly logically) possible, then physicalism is false. That's their job: to serve as counterexamples to physicalism. For if zombies are possible, then it is not the case that every nonphysical property-instantiation supervenes upon a physical property-instantiation: a zombie has all the same physical properties as its indiscernible non-zombie twin, but is not conscious. The possibility of zombies implies that consciousness is non-supervenient, something in addition to a being's physical makeup. So one anti-physicalist argument goes like this:
1. If physicalism is true, then every nonphysical property-instantiation supervenes upon a physical property-instantiation.
2. If zombies are possible, then it is not the case that every nonphysical property-instantiation supervenes upon a physical property-instantiation.
3. Zombies are possible.
Therefore
4. Physicalism is not true.
This is a valid argument the soundness of which rides on premise (3). Here is where the fight will come. Without questioning the validity of the argument the physicalist will run the argument in reverse. He will deny the conclusion and then deny (3). In effect, he will argue from (1) & (2) & (~4) to (~3). He will deny the very possibility of zombies. He will insist that anything that behaves just like a conscious person and has the 'innards' of a conscious person JUST IS a conscious person.
Now I find that absurd: it is a denial of that subjectivity which is properly accessed only via the irreducible first-person singular point of view. Nevertheless, I will have a devil of a time budging my materialist-functionalist interlocutor. Materialists are objectivists: they think that anything that is not objectively accessible in the third-person way just isn't there at all, or it if is 'there,' is not to be taken seriously.
Can one support (3) in a manner so compelling as to convince the recalcitrant materialist? After all, (3) is not self-evident. If it were self-evident, then we would have a 'knock-down' argument against physicalism. But there are few if any 'knock-down' (absolutely compelling) arguments in philosophy.
Now zombies are certainly conceivable. But it is not clear whether conceivability entails metaphysical (broadly logical) possibility, which is in play in (3). So it is not clear whether the conceivability of zombies is a compelling reason to reject physicalism. The question of the relation between conceivability and possibility is a difficult one. There is some discussion of this in the conceivability category.
Now here is what Galen Strawson has to say:
4. Strawson on Zombies.
It is, finally, a mistake to think that we can know that ‘zombies’ could exist—where zombies are understood to be creatures that have no experiential properties although they are perfect physical duplicates (PPDs) of currently experiencing human beings like you and me.
The argument that PPD-zombies could exist proceeds from two premisses—[1] it is conceivable that PPD-zombies exist, [2] if something is conceivable, then it is possible. It is plainly valid, and (unlike many) I have no insuperable problem with [2]. The problem is that we can't know [1] to be true, and have no reason to think it is. To be a materialist is, precisely, to hold that it is false, and while materialism cannot be known to be true, it cannot be refuted a priori—as it could be if [1] were established. ‘Physical’, recall, is a natural kind term, and since we know that there is much that we do not know about the nature of the physical, we cannot claim to know that an experienceless PPD of a currently experiencing human being is conceivable, and could possibly (or ‘in some possible world’) exist.
This is just blatant question-begging on Strawson's part. We can't know that it is conceivable that zombies exist?! That zombies are conceivable is a very weak claim, and of course we can know it to be true, just by conceiving a zombie, whence it follows that we have excellent reason to think it is true. Strawson simply begs the question by assuming that materialism is true. He also begs the question by claiming that materialism cannot be refuted a priori. If you grant [2], as Strawson does, then what we have is an a priori refutation of materialism.
Strawson tells us that 'physical' is a natural kind term. What a strange idea! 'Water,' 'gold, 'tiger' are uncontroversial natural kind terms. They succeed in referring to what they were introduced to refer to despite our knowledge or ignorance of the nature of what they refer to. The ancient Greeks thought water was an element; Dalton held it to be HO; we take it to be H2O. Water turned out to be a lot different than we thought, without prejudice to the reference of 'water.' So if 'physical' is a natural kind term, then it too can refer to things very different in nature than what we might have supposed. And so Strawson thinks that 'physical' can refer to what is irreducibly mental or experiential in whole or in part. In fact, Strawson allows that the physical — that which physics studies — could be wholly mental.
I don't know what this means. Perhaps Vlastimil can explain it to me.
Does Matter Think?
If matter (wholly material beings) could think, then matter would not be matter as currently understood.
Can abstracta think? Sets count as abstracta. Can a set think? Could the set of primes contemplate itself and think the thought, I am a set, and each of my members is a prime number? Given what we know sets to be from set theory, sets cannot think. It is the same with matter. Given what we know or believe matter to be from current physics, matter cannot think. To think is to think about something, and it is this intrinsic aboutness or original intentionality that proves embarrassing for materialism. I have expatiated on this over many, many posts and I can't repeat myself here. (Here is a characteristic post.)
But couldn't matter have occult powers, powers presently hidden from our best physics, including the power to think? Well, could sets have occult powers that a more penetrating set theory would lay bare? Should we pin our hopes on future set theory? Obviously not. Why not? Because it makes no sense to think of sets as subjects of intentional states. We know a priori that the set of primes cannot lust after the set of evens. It is impossible in a very strong sense: it is broadly logically impossible.
Of course, there is a big difference between sets and brains. We know enough about sets to know a priori that sets cannot think. But perhaps we don't yet know enough about the human brain. So I don't dogmatically claim that matter could not have occult or hidden powers. Maybe the meat between my ears does have the power to think. But then that meat is not matter in any sense we currently understand. And that is my point. You can posit occult powers if you like, and pin your hopes on a future science that will lay them bare; but then you are going well beyond the empirical evidence and engaging in high-flying speculations that ought to seem unseemly to hard-headed empiricistic and scientistic types.
Such types are known to complain about spook stuff and ghosts-in-machines. But to impute occult powers, powers beyond our ken, to brain matter does not seem to be much of an improvement. For that is a sort of dualism too. There are the physical properties and powers we know about, and the physical properties and powers we know nothing about but posit to avoid the absurdities of identity materialism and eliminativism. So instead of an ontological property dualism or an ontological substance dualism we have an epistemological property dualism, a dualism as between properties and powers we know about and properties and powers we have no idea about.
There is, second, the ontological dualism as between thinking and feeling matter and ordinary hunks of matter that do not think or feel. Even the materialist must admit that there is a huge difference between Einstein and a piece of chalk. How explain that some parcels of matter think and some do not?
It is worth noting that the reverent gushing of the neuro-scientistic types over the incredible complexity (pound the lectern!) of the brain does absolutely nothing to reduce the unintelligibility of the notion that it is brains or parts of brains that are the subjects of intentional and qualitative mental states. For it is unintelligible how ramping up complexity can trigger a metabasis eis allo genos, a shift into another genus. Are you telling me that meat that means is just meat that is more complex than ordinary meat? You might as well say that the leap from unmeaning meat to meaning meat is a miracle. Will you say that consciousness emerges from certain parcels of sufficiently complex matter? But then it is not matter any more, is it? It is an emergent from matter. Emergentism is a form of ontological dualism. What's more, the word 'emergence' merely papers over the difficulty, labeling the problem without solving it. Do you materialists believe in miracle meat or mystery meat? Do you believe in magic?
There is, third, a dualism within the brain as between those parts of it that are presumably thinking and feeling and those other parts that perform more mundane functions. Why are some brain states mental and others not?
The materialist operates with a conception of matter tied to current physics. On that conception of matter, it is simply unintelligible to to say that brains feel or think. I tend to hold that this unintelligibility is a very good reason to hold that it is not my brain or any part thereof that thinks when I think, and that it is not my brain or any part thereof that feels when I feel. (I am using 'think' in the broad Cartesian sense to cover all instances of intentionality, and 'feel' to cover all non-intentional conscious states and events.)
"But from the fact that such-and-such is unintelligible to us now it does not follow that it is not the case." True. Two possibilities. It might be the case that p even though we will never understand how it is possible that p, and it might be the case that p, even though we cannot understand at present how it is possible that p. The first is a mysterian position, the second is not mysterian but a pin-hopes-on-future-science position.
My thesis is that it is reasonable to hold that when I think and feel it is not my brain or any part of it that thinks or feels. But who knows? Maybe future science will prove me wrong. It is just that I wouldn't lay any money on being wrong.
Galen Strawson Versus Nicholas Humphrey on Consciousness
(This is a repost from February 2013 slightly emended, except for an addendum added today. Reposts are the reruns of the blogosphere. You don't watch a Twilight Zone or Seinfeld episode just once do you?)
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A couple of days ago I had Nicholas Humphrey in my sights. Or, to revert to the metaphor of that post, I took a shovel to his bull. I am happy to see that Galen Strawson agrees that it is just nonsense to speak of consciousness as an illusion. Strawson's trenchant review of Humphrey's Soul Dust: The Magic of Consciousness is here. Unfortunately, I cannot see that Strawson has shed much light either, at least judging from the sketch of his position presented in the just-mentioned review:
There is no mystery of consciousness as standardly presented, although book after book tells us that there is, including, now, Nick Humphrey's Soul Dust: The Magic of Consciousness. We know exactly what consciousness is; we know it in seeing, tasting, touching, smelling, hearing, in hunger, fever, nausea, joy, boredom, the shower, childbirth, walking down the road. If someone denies this or demands a definition of consciousness, there are two very good responses. The first is Louis Armstrong's, when he was asked what jazz is: "If you got to ask, you ain't never goin' to know." The second is gentler: "You know what it is from your own case." You know what consciousness is in general, you know the intrinsic nature of consciousness, just in being conscious at all.
"Yes, yes," say the proponents of magic, "but there's still a mystery: how can all this vivid conscious experience be physical, merely and wholly physical?" (I'm assuming, with them, that we're wholly physical beings.) This, though, is the 400-year-old mistake. In speaking of the "magical mystery show", Humphrey and many others make a colossal and crucial assumption: the assumption that we know something about the intrinsic nature of matter that gives us reason to think that it's surprising that it involves consciousness. We don't. Nor is this news. Locke knew it in 1689, as did Hume in 1739. Philosopher-chemist Joseph Priestley was extremely clear about it in the 1770s. So were Eddington, Russell and Whitehead in the 1920s.
One thing we do know about matter is that when you put some very common-or-garden elements (carbon, hydrogen, oxygen, sodium, potassium, etc) together in the way in which they're put together in brains, you get consciousness like ours – a wholly physical phenomenon. (It's happening to you right now.) And this means that we do, after all, know something about the intrinsic nature of matter, over and above everything we know in knowing the equations of physics. Why? Because we know the intrinsic nature of consciousness and consciousness is a form of matter.
The main point of Strawson's first paragraph is surely correct: we know what consciousness is in the most direct and unmistakable way possible: we experience it, we live through it, we are it. We know it from our own case, immediately, and we know it better than we know anything else. If Dennett doesn't know what a sensory quale is, then perhaps the cure is to administer a sharp kick to his groin. Feel that, Dan? That's a quale. (I am assuming, of course, that Dennett is not a 'zombie' in the technical sense in which that term is used in philosophy of mind discussions. But I can't prove he isn't. Perhaps that is the problem. If he were a zombie, then maybe all his verbal behavior would be understandable.)
In the second paragraph Strawson rejects an assumption and he makes one himself. He rejects the assumption that we know enough about the intrinsic nature of matter to know that a material being cannot think. The assumption he makes is that we are wholly physical beings. So far I understand him. It could be that (it is epistemically possible that) this stuff inside my skull is the thinker of my thoughts. This is epistemically possible because matter could have hidden powers that we have yet to fathom. On our current understanding of matter it makes no bloody sense to maintain that matter thinks; but that may merely reflect our ignorance of the intrinsic nature of matter. So I cannot quickly dismiss the notion that matter thinks in the way I can quickly dismiss the preternaturally boneheaded notion that consciousness is an illusion.
I agree with Strawson's first paragraph; I understand the second; but I am flabbergasted by the third. For now our man waxes dogmatic and postures as if he KNOWS that consciousness is a wholly physical phenomenon. How does he know it? Obviously, he doesn't know it. It is a mere conjecture, an intelligible conjecture, and perhaps even a reasonable one. After all it might be (it is epistemically possible that) the matter of our brains has occult powers that physics has yet to lay bare, powers that enable it to think and feel. I cannot exclude this epistemic possibility, any more than Strawson can exclude the possibility that thinkers are spiritual substances. But to conjecture that things might be thus and so is not to KNOW that they are thus and so. All we can claim to KNOW is what Strawson asseverates in his first paragraph.
Here is Strawson's argument in a nutshell:
1. We know the intrinsic nature of consciousness from our own case.
2. We know that consciousness is a form of matter.
Ergo
3. There is nothing mysterious about consciousness or about how matter gives rise to consciousness; nor is there any question whether consciousness is wholly physical; the only mystery concerns the intrinsic nature of matter.
The problem with this argument is premise (2). It is pure bluster: a wholly gratuitous assumption, a mere dogma of naturalism. I can neutralize the argument with this counterargument:
4. If (1) & (2), then brain matter has occult powers.
5. We have no good reason to assume — it is wholly gratuitous to assume — that brain matter has occult powers.
Therefore
6. We have no good reason to assume that both (1) and (2) are true.
7. We know that (1) is true.
Therefore
8. We have good reason to believe that (2) is false.
Further Thoughts: Strawsonian Theology? (20 September 2015)
Strawson tells us that he is assuming that we are "wholly physical beings." Now a proposition cannot be true or false unless it is meaningful. But what does it even mean to say that we are wholly physical beings given that this entails that some wholly physical beings are conscious and self-conscious? What does 'physical' mean if beings as richly endowed with mentality as we are count as "wholly physical"? There is a semantic problem here, and it looks to be a failure of contrast. 'Physical' contrasts with 'mental' and has a specific meaning in virtue of this contrast. And vice versa. So if nothing is mental, then nothing is physical in the specific contrastive sense that lends 'bite' and interest to the thesis that we are wholly physical. To put it another way, if nothing is mental and everything is physical including us with our richly endowed inner lives, then the claim that we are wholly physical is not particularly interesting. It is nearly vacuous if not wholly vacuous. It has been evacuated of its meaning by a failure of contrast. If we are wholly physical in an umbrella sense that subsumes the contrastive senses of 'physical' and 'mental,' then Strawson has merely papered over the problem of how the mental and the physical are related when these terms are taken in their specific senses.
Suppose Einstein and his blackboard are both wholly physical. We still have to account for the fact that one of them is conscious and entertains thoughts while the other isn't and doesn't. That is a huge difference. What Strawson has to say is that in us thinking and feeling beings powers of matter are exercised that are not exercised in other, less distinguished clumps of matter. Hidden in the bosom of matter are powers that a future physics may lay bare and render intelligible.
But if Strawson widens his concept of matter to cover both thinking and nonthinking matter, does he have a principled way to prevent an even further widening?
If minds like ours are wholly physical, why can't God be wholly physical? God is a mind too. Presumably God cannot be wholly physical because God is not in space and is not subject to physical decomposition. But if we can be wholly physical despite the fact that we think and are conscious — if there is nothing in the nature of matter to rule out thought and consciousness — then perhaps there is nothing in the nature of matter to rule out material beings that have no spatial location and are not subject to physical decomposition.
If an advanced physics will reveal how meat heads like us can think, then perhaps there are other properties and possibilities of matter hitherto undreamt of. Consider Christ's Ascension, body and soul, into heaven. Christ's Ascension is not a dematerialization: he ascends bodily into a purely spiritual, nonphysical, 'dimension.' Without losing his (resurrected) body, Christ ascends to the Father so that, after the Ascension, the Second Person of the Trinity acquires Christ's resurrected body. On our ordinary way of thinking, this is utterly unintelligible. God is pure spirit, pure mind. How can Christ ascend bodily into heaven, and without divesting himself of his body, enter into the unity of the purely spiritual Trinity? It is unintelligible to us because it issues in a formal-logical contradiction: God is wholly nonphysical and also in part physical. A mysterian would say it is a mystery. It happened, so it's possible, and this regardless of its unintelligibility to us.
On Strawson's approach there needn't be any mystery here: some parcels of matter have amazing powers. For example, we are wholly material and yet we think and feel. It is truly amazing that we should be thinking meat! If so, God might be a parcel of matter that thinks, feels, and — without prejudice to his physicality — has no spatial location and is not subject to physical decomposition. If so, the Ascension is comprehensible: Christ ascends bodily to join the physical Trinity. It is just that he sheds his particular location and his physical mutability. He remains what he was on earth, an embodied soul.
The same could be said of the Assumption of the Blessed Virgin Mary into heaven. She too entered bodily into heaven. On a Strawsonian theology, this might be rendered intelligible without mysterianism.
To sum up. If matter actually thinks and feels in us, as Strawson holds, then he has widened the concept of matter to embrace both 'ordinary' matter and sentient, thinking, 'spiritual' matter. But then what principled way would Strawson have to prevent a further widening of the concept of matter so that it embraces God, disembodied souls, angels, and what not?
Eyes in the Mirror
The eyes you see in the mirror when you look at yourself are not seeing eyes but seen eyes. Strange but true: your seeing eyes are and must remain invisible.
Mysterian Materialism and Mysterian Trinitarianism
Here are some thoughts that may provoke a fruitful discussion with Vlastimil Vohanka on the topic of mysterianism in the philosophy of mind and in theology. He kindly sent me his rich and stimulating paper, "Mysterianism about Consciousness and the Trinity." The paper is available here along with other works of his. His view is that a mysterian line is defensible in both the philosophy of mind and in Trinitarian theology. I have some doubts.
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There are different sorts of materialism about the mind, among them eliminative materialism, identity-materialism, and functionalism. There is also mysterian materialism. Here is a little speech by a mysterian materialist:
Look, we are just complex physical systems, nothing more. And yet we think and are conscious. Therefore, we are wholly material beings who think and are conscious. We cannot understand how this is possible. But what is actual is possible whether or we we are able to understand how it is possible. So the fact that we cannot understand how it is possible that thinking and consciousness are nothing more than brain activity does not show that they are not brain activity. It shows that the how is beyond our understanding. What we have here, then, is a mystery: a proposition that is true and non-contradictory despite our inability to understand how it could be true.
What motivates this mysterian materialism? Two things. There is first of all the deep conviction shared by many today that there is exactly one world, this mind-independent physical world, that we are parts of it, that nothing in us is not part of it, and that it and us are wholly natural and in no respect supernatural. This naturalist conviction implies that there is nothing special about us, that we are continuous with the rest of nature. We are nothing special in that we have no higher origin or higher destiny. There is no God who created us in his image and likeness. And there is no higher happiness other than the transient and fitful happiness that some of us can eke out, if we are lucky, here below. We are irremediably mortal and natural, like everything else that lives, and anything (conscience, consciousness, self-consciousness, ability to reason, love and longing, sensus divinitatis, etc.) that suggests otherwise is susceptible of a wholly naturalistic explanation. Part of why people embrace the naturalist conviction is that it puts paid to central tenets of old-time religion: God, the soul, post-mortem rewards and punishments, the libertarian freedom of the will, man's being an image and likeness of God, etc. So hostility to religion is certainly, for some, part of the psychological (if not logical) motivation for the acceptance of the naturalist conviction.
Now take the naturalist conviction and conjoin it to the intellectually honest admission that we have no idea at all how it is so much as possible for a wholly material being to think and enjoy conscious states. The conjunction of the Conviction and the Admission generates a mysterian position according to which one affirms as true a proposition that one cannot understand as possibly true, a proposition that for us is and most likely will remain unintelligible, namely, the proposition that we are wholly material beings susceptible of exhaustive natural-scientific explanation who nonetheless think, feel, love, make moral demands, feel subject to them, etc.
This mysterianism is an epistemological position according to which our contingent but unalterable make-up makes it impossible for us ever to understand how it is possible for us to think and be conscious. The claim is not that thought and consciousness are mysterious because they are non-natural phenomena; the claim is that they are wholly natural but not understandable by us. Our cognitive architecture (a phrase I believe Colin McGinn employs) blocks our epistemic access to those properties the understanding of which would render intelligible to us how we can be both wholly material and yet the subjects of intentional and non-intentional mental states.
Well, this mysterianism is certainly to be preferred to an eliminativism which argues from the unintelligibility of a material thing's thinking to the nonexistence of its thinking. But eliminativism is a lunatic position best left to the exceedingly intelligent lunatics who dreamt it up. I won't waste any words here refuting this mindless doctrine; I have wasted words elsewhere.
We should note that one could be a mysterian in the philosophy of mind without being a mysterian materialist. One could be a mysterian substance dualist. Some maintain that the interaction problem dooms substance dualism. A mysterian might hold that substance dualism is true, that mind-body interaction is unintelligible, that interaction occurs, and that our inability to understand how mind-body interaction occurs merely shows a cognitive limitation on our part. It seems obvious that there is nothing in the nature of mysterianism in the philosophy of mind to require that one be a mysterian materialist/physicalist/naturalist.
We should also note that one could be a mysterian in areas other than the philosophy of mind, in theology, for example.
Mysterianism as a general strategy rests on a fairly solid foundation. First of all, it is a self-evident modal axiom that actuality entails possiblity. It is also self-evident that if x is possible, then it does not follow that we are in a position to understand how it is possible. So it may well be that there are certain objects and states of affairs and phenomena whose internal possibility we cannot discern due to our irremediable cognitive limitations. Apparent contradictoriness would then not argue unreality.
But surely there is something very strange about maintaining that there are true mysteries. A true mystery is a true proposition that is unintelligible to us, though not unintelligible in itself. Now here is my difficulty in a nutshell. If a proposition either is or entails a broadly-logical contradiction, then I wouldn't know what I had before my mind if I had such a proposition before my mind. And if I didn't know exactly which proposition I had before my mind, I wouldn't know exactly which proposition I was claiming was both true and mysterious.
Bear with me as I try to clarify my objection.
Before I can take a position with respect to a proposition I must know what that proposition is. I must know the identity of the proposition. But a proposition that strikes my mind as unintelligible is not one about whose identity I can be sure.
I count four positions or attitudes one can take toward a proposition: accept as true, reject as false, suspend judgment as to truth-value, practice epoché , ἐποχή. Pithier still: Accept, Reject, Suspend, Withdraw. The first three are self-explanatory. By Withdraw I mean: take no position on whether or not there is even a proposition (ein Gedanke, a complete thought) before one's mind. (The notion of Withdrawal is derived via Benson Mates from Sextus Empiricus.) Withdrawal goes farther than Suspension. To suspend is to refuse to accept or reject a well-defined proposition while accepting that there is such a proposition before one's mind. In the state of Withdrawal I take no position on whether or not there is a well-defined proposition before my mind. In the state of Withdrawal I have before my mind a verbal formulation, and the senses of its constituent words, but I take no position on the question whether the verbal formulation expresses a proposition.
Example. A Trinitarian says, 'There is exactly one God in three divine persons.' Studying the doctrine I come to the conclusion that I can attach no definite sense to it on the ground that it seems to me to entail one or more logical contradictions. That is not a case of rejection or of suspension; it is a case of epoché. I 'bracket' (to borrow a term from Husserl) two questions: the question as to truth-value, and the more fundamental question as to whether or not there is even a proposition (a unified, coherent, sense-structure) before my mind as opposed to an incoherent, un-unified bunch of word-senses.
Suppose you say to me, "Snow is white and snow is not white." Being the charitable fellow that I am known to be, I would not churlishly impute to you the assertion of a formal-logical contradiction. I would take you to be using a contradictory form of words to express a non-contradictory proposition, perhaps, the proposition that snow is white where I didn't relieve myself, but not white where I did. Or something like that. The time-honored method of showing an apparent contradiction to be merely apparent is by making a distinction in respect of time, or respect, or word sense.
But if someone insists that he means literally that snow is white and snow is not white where there is no distinction in respect of time, respect, or sense of the word 'white,' then I wouldn't know what the content of the assertion was. I wouldn't know which proposition my interlocutor was trying get across to me. For if my interlocutor was otherwise rational, the Principle of Charity would forbid me from imputing a contradiction to him. I would have to practice withdrawal.
If you say with a straight face "Snow is white and snow is not white" and you are neither equivocating on any term, nor making any distinction with respect to time or respect, and I charitably refuse to impute to you the assertion of a formal-logical contradiction of the form *p & ~p,* then I must say that I have no idea at all which proposition you are trying to convey to me. And so I naturally practice epoché with respect to your utterance.
(I grant that there is a sense in which a self-contradictory proposition — *No dog is a dog* for example — is intelligible (understandable): for if I did not understand the proposition I would not understand it to be self-contradictory and thus necessarily false. What I mean by 'intelligible' here is 'understandable as broadly-logically possibly true.' On this narrow use of 'intelligible,' a claim to the effect that no dog is a dog or that snow both is and is not white is unintelligible.)
Back to the mysterian materialist. I must put his asseverations within the Husserlian brackets. He bids me accept propositions that as far as I can tell are not propositions at all. A proposition is a sense, but the 'propositions' he bids me accept make no sense. For example, he wants me to accept that my present memories of Boston are all identical to states of my brain. That makes no sense. Memory states are intentional states: they have content. No physical state has content, or could have content. So no intentional state could be a physical state. The very idea is unintelligible. To be precise: it is unintelligible as something broadly logically possible. The vocabularies we use when speaking of brain states and mental states respectively are radically incommensurable. Axon, dendrite, synapse, etc. on the one hand, qualia, intentionality, content, etc. on the other. Even if one were to know everything there is to know about the electro-chemistry and neuro-anatomy of the brain one would still have no clue as to how consciousness arises from it. By consciousness, I mean not only qualia but intentional (object-directed) states.
But where there are no thoughts one can always mouth words. So one can mouth the words, 'Memories are in the head' or 'Thoughts are literally brain states.' But one cannot attach a non-contradictory thought to the words.
No doubt there is an illusion of sense. There is nothing syntactically wrong with 'Thoughts are brain states' or 'Sensory qualia are physical features of the brain.' And the individual words have meaning. What's more, the words taken together seem to convey a coherent thought in the way in which 'Quadruplicity drinks procrastination' does not seem to convey a coherent thought. But when the meaning is made explicit, the unintelligibility becomes manifest.
To say of a sensory quale q that it is identical to a brain state b is to say something that is unintelligible. For if q = b, then they share all properties, by the Indiscernibility of Identicals, a principle than which no more luminous can be conceived. But it is plain that they do not share all properties: the quale but not the brain state has a phenomenological feel, a Nagelian what it-is-like, an element of irreducible subjectivity. Thus the materialist identity claim is seen with a just a tiny bit of reasoning to be utterly unintelligible.
If you tell me that one and the same item in my skull has both physical and phenomenological properties, then I say you have changed the subject: you now have a dual-aspect theory going. I will then press you on what this third item is that has both physical and phenomenological features.
Suppose you stick to the topic but make a mysterian move. You grant me that it is unintelligible for us that q = b, but insist that it is intelligible in itself. You say it is true in reality despite the irremediable appearance of unintelligibility. It is true and non-contradictory in reality that sensory qualia and thoughts are nothing other than events or processes transpiring inside the skull. You say it is true and non-contradictory that when I think about Boston that thinking is just something going on in my head, adding that it is and will remain a mystery how this could be.
My objection can be put as follows. We have a verbal formulation (VF) such as 'Qualia are brain states.' VF expresses the unintelligible-for-us proposition (UFUP) *Qualia are brain states.* We are told that VF is true even though we, with our cognitive limitations, cannot understand how it is true or even how it could be true. So there must be a true intelligible-in-itself proposition (IIIP) distinct from (UFUP) to which we have no access. How is IIIP related to VF? It cannot be that VF expresses IIIP. VF expresses UFUP. So we are supposed to accept a proposition to which we have no access, a proposition that stands in no specifiable relation to VF. But surely that I cannot do. I cannot accept a proposition to which I have no access.
The formulations of the trinitarian theist appear to be in the same logical boat. I am of course assuming that the logical problem of the Trinity cannot be solved on the discursive plane. That is, one cannot solve it in the usual way by making distinctions. If one could solve it in this way, then there would be no need to make a mysterian move. The doctrine would be rationally acceptable as it stands, though not rationally provable since the triunity of God can be known only by revelation.
To sum up my objection. We are offered a verbal formulation, e.g., "There is one God in three divine persons." This verbal formulation expresses a proposition that is unintelligible to us. (It is unintelligible to us because contradictions can be derived from it using given doctrinal elements and unquestionable notions such as the transitivity of identity.) We are assured, however, that while the manifest proposition is unintelligible to us, the verbal formulation expresses a second proposition that is true and intelligible in itself. But since this proposition is inaccessible, one annot accept it, reject it, or suspend judgment with respect to it.
If you tell me that there are not two propositions, but that one and the same proposition is both unintelligible to us but intelligible in itself, then I will ask you which proposition this is.
I suppose what I am saying is that a true proposition that is a mystery is an item so indeterminate that one cannot take up any attitude to it except that of Withdrawal or epoché as I defined this term.
Which is Harder to Conceive?
Which is harder to conceive, that something wholly immaterial could be alive or that something wholly material could be alive?
Some Philosophical Positions Valuable Only as Foils: Extreme Nominalism and Eliminative Materialism
By a philosophical foil I mean a view or position that contrasts with other positions in such a way as to highlight the often superior qualities of the other positions. Foils are useful for mapping the spaces of theories and as termini of theoretical spectra. Consider the spectrum of positions stretching from extreme nominalism to Plato's Theory of Forms. The end points are reasonably viewed as foils. It seems to me that some philosophical positions are valuable and worthy of study only as foils and not as serious candidates for the office of 'true theory.' Here are two of several examples. Since everything in philosophy is controverted, I expect these will be too. The foil of one is the truth of another. Ain't philosophy grand? But I like the following examples, and I am the man whose intellectual and spiritual exigencies I am most interested in satisfying.
- Extreme Nominalism. This is the view that there are no properties. If you tell me that there are no properties, I will be inclined to 'show you the door.' Of course there are properties. The only reasonable questions pertain to their nature. Are they universals or particulars? Can they exist unexemplified or not? Are they constituents of the things that have them or not? Is there a property for every meaningful predicate? Are there disjunctive properties? And so on. The reasonable question is not whether there are properties, but what they are.
- Eliminative Materialism. This is surely a lunatic philosophy of mind. An eliminative materialist is a bit like a person who blows her brains out to be rid of a headache. No head, no headache, no problem! Too quick you say? Perhaps. So let me expatiate further.
The most obvious objection to eliminative materialism (EM) is that it denies obvious data, the very data without which there would be no philosophy of mind in the first place. Introspection directly reveals the existence of pains, anxieties, pleasures, and the like. Suppose I have a headache. The pain, qua felt, cannot be doubted or denied. Its esse is its percipi. To identify the pain with a brain state makes a modicum of sense, at least initially; but it makes no sense at all to deny the existence of the very datum that gets us discussing this topic in the first place. But Paul M. Churchland (Matter and Consciousness, rev. ed. MIT Press, 1988, pp. 47-48) has a response to this sort of objection:
The eliminative materialist will reply that that argument makes the same
mistake that an ancient or medieval person would be making if he insisted that
he could just see with his own eyes that the heavens form a turning sphere, or
that witches exist. The fact is, all observation occurs within some system of
concepts, and our observation judgments are only as good as the conceptual
framework in which they are expressed. In all three cases — the starry sphere,
witches, and the familiar mental states — precisely what is challenged is the
integrity of the background conceptual frameworks in which the observation
judgments are expressed. To insist on the validity of one's experiences,
traditionally interpreted, is therefore to beg the very question at issue. For
in all three cases, the question is whether we should reconceive the
nature of some familiar observational domain.Even if we grant that "all observation occurs within some system of concepts," is the experiencing of a pain a case of observation? If you know your Brentano, you know that early on in Psychology From an Empirical Standpoint he makes a distinction between inner observation (innere Beobachtung) and inner perception (innere Warhnehmung). Suppose one suddenly becomes angry. The experiencing of anger is an inner perception, but not an inner observation. The difference is between living in and through one's anger and objectifying it in an act of reflection. The act of inner observation causes the anger to subside, unlike the inner perception which does not.
Reflecting on this phenomenological difference, one sees how crude Churchland's scheme is. He thinks that mental data such as pains and pleasures are on a par with outer objects like stars and planets. It is readily granted with respect to the latter that seeing is seeing-as. A medieval man who sees the heavens as a turning sphere is interpreting the visual data in the light of a false theory; he is applying an outmoded conceptual framework. But there is no comparable sense in which my feeling of pain involves the application of a conceptual framework to an inner datum.
Suppose I feel a pain. I might conceptualize it as tooth-ache pain in which case I assign it some such cause as a process of decay in a tooth. But I can 'bracket' or suspend that conceptualization and consider the pain in its purely qualitative, felt, character. It is then nothing more than a sensory quale. I might even go so far as to abstract from its painfulness. This quale, precisely as I experience it, is nothing like a distant object that I conceptualize as this or that.
Now the existence of this rock-bottom sensory datum is indubitable and refutes the eliminativist claim. For this datum is not a product of conceptualization, but is something that is the 'raw material' of conceptualization. The felt pain qua felt is not an object of observation, something external to the observer, but an Erlebnis, something I live-through (er-leben). It is not something outside of me that I subsume under a concept, but a content (Husserl: ein reeller Inhalt) of my consciousness. I live my pain, I don't observe it. It is not a product of conceptualization — in the way a distant light in the sky can be variously conceptualized as a planet, natural satellite, artificial satellite, star, double-star, UFO, etc. — but a matter for conceptualization.
So the answer to Churchland is as follows. There can be no question of re-conceptualizing fundamental sensory data since there was no conceptualization to start with. So I am not begging the question against Churchland when I insist that pains exist: I am not assuming that the "traditional conceptualization" is the correct one. I am denying his presupposition, namely, that there is conceptualization in a case like this.
Most fundamentally, I am questioning the Kantian-Sellarsian presupposition that the data of inner sense are in as much need of categorial interpretation as the data of outer sense. If there is no categorization at this level, then there is no possibility of a re-categorization in neuroscientific
terms.What is astonishing about eliminative materialists is that they refuse to take the blatant falsity of their conclusions as showing that they went wrong somewhere in their reasoning. In the grip of their scientistic assumptions, they deny the very data that any reasonable person would take as a plain refutation of their claims.
Memory, Matter, Mind
Memory loss points to the materiality of mind while memory's exercise points to its immateriality. Mind is mysterious, but memorial mind is even more so, situated as it is at the crossroads of intentionality and time.
The Hard Problem Now a Play
By Tom Stoppard. Via Daniel McInerny via Tom Coleman.
I have always thought the 'hard problem' vs. 'easy problem' distinction in the philosophy of mind to be rather silly.
Marcia Cavell Defends Colin McGinn Against the “Hysterical” Patricia Churchland
Here, with a response by McGinn. Merits the coveted MavPhil imprimatur and nihil obstat.
In fairness to Churchland, it is her letter, not her, that Cavell calls "hysterical." A politically incorrect word these days, I should think. Isn't 'hysterical' etymologically related to the Latin and Greek words for womb? According to the Online Etymology Dictionary:
- hysterical (adj.)
- 1610s, from Latin hystericus "of the womb," from Greek hysterikos "of the womb, suffering in the womb," from hystera "womb" (see uterus). Originally defined as a neurotic condition peculiar to women and thought to be caused by a dysfunction of the uterus. Meaning "very funny" (by 1939) is from the notion of uncontrollable fits of laughter. Related: Hysterically.
The Academic Philosophers of Consciousness
Too many of the academic philosophers of consciousness are overly concerned with the paltriest aspects of consciousness, so-called qualia, and work their tails off trying to convince themselves and others that they are no threat to physicalism.
While man's nobility lies in the power of thought whereby he traverses all of time and existence, our materialists labor mightily to make physicalism safe for the smell of cooked onions.
Patricia Churchland versus Colin McGinn on Mysterianism
It's a win for McGinn.
Here's Churchland:
The view for which McGinn is known is a jejune prediction, namely that science cannot ever solve the problem of how the brain produces consciousness. On what does he base his prediction? Flimsy stuff. First, he is pretty sure our brain is not up to the job. Why not? Try this: a blind man does not experience color, and he will not do so even when we explain the brain mechanisms of experiencing color. Added to which, McGinn says that he cannot begin to imagine what it is like to be a bat, or how conscious experience might be scientifically explained (his brain not being up to the job, as he insists). This cognitive inadequacy he deems to have universal epistemological significance.
Alongside the arrogance, here is one whopping flaw: no causal explanation for a phenomenon, such as color vision, should be expected to actually produce that phenomenon. Here is why: the neural pathways involved in visually experiencing color are not the same pathways as those involved in intellectually understanding the mechanisms for experiencing color. Roughly speaking, experiencing color depends on areas in the back of the brain (visual areas) and intellectual understanding of an explanation depends on areas in the front of the brain.
Now what does this snark and misdirection have to do with anything McGinn actually maintains? Nothing that I can see. Here's McGinn:
Churchland’s account of my arguments for our cognitive limitations with respect to explaining consciousness bears little relation to what I have written in several books, as anyone who has dipped into those books will appreciate. What she refers to as a “whopping flaw” in my position (and that of many others) is simply a complete misreading of what has been argued: the point is not that having a causal explanation for a phenomenon should produce that phenomenon, so that a blind man will be made to see by having a good theory of vision. The point is rather that a blind man will not understand what color vision is merely by finding out about the brain mechanisms that underlie it, since he needs acquaintance with the color experiences themselves.
Churchland 0 – McGinn 1.
The articles below should help you understand some of the issues.
Must Singular Thoughts be Object-Dependent?
What follows are some ideas from London Ed about a book he is writing. He solicits comments. Mine are in blue.
The logical form thing was entertaining but rather off-topic re the fictional names thing. On which, Peter requested some more.
Let’s step right back. I want to kick off the book with an observation about how illusion impedes the progress of science. It looks as though the sun is going round the earth, so early theories of the universe had the earth standing still. It seems as though objects are continuously solid, and so science rejected the atomists’ theory and adopted Aristotle’s theory for more than a millenium.
A final example from the psychology of perception: in 1638, Descartes takes a eye of a bull and shows how images are projected onto the retina. He finally disproves the ‘emissive theory of sight’. The emissive theory is the naturally occurring idea that eyesight is emitted from your eye and travels to and hits the distant object you are looking at. If you ask a young child why you can’t see when your eyes are shut, he replies (‘because the eyesight can’t get out’).
Scientific progress is [often] about rejecting theories based on what our cognitive and perceptual framework suggests to us, and adopting theories based on diligent observation and logic.
We reject ‘eyebeams’. We reject the natural idea that the mental or sensitive faculty can act at a distance. When we look at the moon, science rejects the idea that a little ethereal piece of us is travelling a quarter of a million miles into space. Yet – turning to the main subject of the book – some philosophers think that objects themselves somehow enter our thoughts. Russell writes to Frege, saying “I believe that in spite of all its snowfields Mont Blanc itself is a component part of what is actually asserted in the proposition ‘Mont Blanc is more than 4,000 metres high”. Kaplan mentions, with apparent approval, the idea that the proposition ‘John is tall’ has two components: the property expressed by the predicate ‘is tall’, and the individual John. “That’s right, John himself, right there, trapped in a proposition”. The dominant theory in modern philosophical logic is ‘direct reference’, or object-dependent theories of semantics: a proper name has no meaning except its bearer, and so the meaning of ‘John is tall’ has precisely the components that Kaplan describes.
BV: I too find the notion that there are Russellian (as opposed to Fregean) propositions very hard to swallow. If belief is a propositional attitude, and I believe that Peter is now doing his grades, it is surely not Peter himself, intestinal contents and all, who is a constituent of the proposition that is the accusative of my act of belief. The subject constituent of the proposition cannot be that infinitely propertied gnarly chunk of external reality, but must be a thinner sort of object, one manageable by a finite mind, something along the lines of a Fregean sense.
The purpose of the proposed book is to advance science by showing how such object-dependent theories are deeply mistaken, and also to explain why they are so compelling, because of their basis on a cognitive illusion as powerful as the illusions that underlie the geocentric theory, or the emissive theory of sight.
What is the illusion? The argument for object dependence is roughly as follows
(1) We can have so-called ‘singular thoughts’, such as when we think that John is tall, i.e. when we have thoughts expressable [expressible] by propositions [sentences, not propositions] whose subject term is a proper name or some other non-descriptive singular term.
(2) A singular term tells us which individual the proposition is about, without telling us anything about it. I.e. singular terms, proper names, demonstratives, etc. are non-descriptive. They are ‘bare individuators’.
BV: This is not quite right. Consider the the first-person singular pronoun, 'I.' This is an indexical expression. If BV says, 'I am hungry,' he refers to BV; if PL says 'I am hungry,' he refers to PL. Either way, something is conveyed about the nature of the referent, namely, that it is a person or a self. So what Ed said is false as it stands. A use of 'I' does tell us something about the individual the sentence containing 'I' is about.
Examples are easily multiplied. Apart from the innovations of the Pee Cee, 'she' tells us that the individual referred to is female. 'Here' tells us that the item denoted is a place, typically. 'Now' picks out times. And there are other examples.
There are no bare items. Hence there cannot be reference to bare items. All reference conveys some property of the thing referred to. But variables may be a counterexample. Consider 'For any x, x = x.' One could perhaps uses variables in such a way that there is no restriction on what they range over. But it might be best to stay away from this labyrinth.
One criticism, then, is that there are no bare individuators. A second is that it is not a singular term, but a use of a singular term that individuates. Thus 'I' individuates nothing. It is PL's use of 'I' that picks out PL.
(3) If a singular term is non-descriptive, its meaning is the individual it individuates. A singular term cannot tell us which individual the proposition is about, unless there exists such an individual.
The course of the book is then to show why we don’t have to be forced into assumption (3). There doesn’t have to be (or to exist) an individual that is individuated. The theory of non-descriptive singular terms is then developed in the way I suggested in my earlier posts. Consider the inference
Frodo is a hobbit
Frodo has large feet
——-
Some hobbit has large feet
I want to argue that the semantics of ‘Frodo’ is purely inferential. I.e. to understand the meaning of ‘Frodo’ in that argument, it is enough to understand the inference that it generates. That is all.
BV: 'Frodo' doesn't generate anything. What you want to say is that the meaning of 'Frodo' is exhausted by the inferential role this term plays in the (valid) argument depicted. Sorry to be such a linguistic prick.
What you are saying is that 'Frodo,' though empty, has a meaning, but this meaning is wholly reducible to the purely syntactical role it plays in the above argument. (So you are not an eliminativist about the meanings of empty names.) But if the role is purely syntactical, then the role of 'Frodo' is the same as the role of the arbitrary individual constant 'f' in the following valid schema:
Hf
Lf
——-
(Ex)(Hx & Lx).
But then what distinguishes the meaning of 'Frodo' from that of 'Gandalf'?
Meinongian nonentities are out. Fregean senses are out. There are no referents in the cases of empty names. And yet they have meaning. So the meaning is purely syntactical. Well, I don't see how you can squeeze meaning out of bare syntax. Again, what distinguishes the meaning of the empty names just cited? The obviously differ in meaning, despite lacking both Sinn and Bedeutung.
We don’t need an object-dependent semantics to explain such inferences, and hence we don’t need object-dependence to explain the semantics of proper names. If an inferential semantics is sufficient, then the Razor tells us it is necesssary: Frustra fit per plura, quod potest fieri per pauciora.
BV: You should state explicitly that you intend your inferential semantics to hold both for empty and nonempty names.
And now we see the illusion. The proposition
John is thinking of Obama (or Frodo, or whomever)
has a relational form: “—is thinking of –”. But it does not express a relation. The illusion consists in the way that the relation of the language so strongly suggests a relation in reality. It is the illusion that causes us “to multiply the things principally signified by terms in accordance with the multiplication of the terms”.
That’s the main idea. Obviously a lot of middle terms have been left out. Have at it.
BV: So I suppose what you are saying is that belief in the intentionality of thought is as illusory as the belief in the emissive theory of sight. Just as the the eye does not emit an ethereal something that travels to the moon, e.g., the mind or the 'I' of the mind — all puns intended! — does not shoot out a ray of intentionality that gloms onto some Meinongian object, or some Thomistic merely intentional object, or some really existent object.
You face two main hurdles. The first I already mentioned. You have to explain how to squeeze semantics from mere syntax. The second is that there are theoretical alternatives to the view that intentionality is a relation other than yours. To mention just one: there are adverbial theories of intentionality that avoid an act-object analysis of mental reference.
John Searle Interviewed
This shot of the old philosopher by the fire with his shootin' ahrn nicely complements some of the combative things he says in the Zan Boag interview at NewPhilosopher. (HT: Karl White.) For example, "I don’t read much philosophy, it upsets me when I read the nonsense written by my contemporaries, the theory of extended mind makes me want to throw up…so mostly I read works of fiction and history."
The surly (Searle-y?) reference is to externalist theories of mind such as Ted Honderich's and Clark and Chalmers' The Extended Mind.
I found this exchange interesting:
You say that consciousness is a real subjective experience, caused by the physical processes of the brain, and that where consciousness is concerned, the appearance is reality. Can you elaborate on this?
John Searle: Consciousness exists only insofar as it is experienced by a human or animal subject. OK, now grant me that consciousness is a genuine biological phenomenon. Well, all the same it’s somewhat different from other biological phenomena because it only exists insofar as it is experienced. However, that does give it an interesting status. You can’t refute the existence of consciousness by showing that it’s just an illusion because the illusion/ reality distinction rests on the difference between how things consciously seem to us and how they really are. But where the very existence of consciousness is concerned, if it consciously seems to me that I’m conscious, then I am conscious. You can’t make the illusion/reality distinction for the very existence of consciousness the way you can for sunsets and rainbows because the distinction is between how things consciously seem and how they really are.
You also say that consciousness is a physical property, like digestion or fire.
John Searle: Consciousness is a biological property like digestion or photosynthesis. Now why isn’t that screamingly obvious to anybody who’s had any education? And I think the answer is these twin traditions. On the one hand there’s God, the soul and immortality that says it’s really not part of the physical world, and then there is the almost as bad tradition of scientific materialism that says it’s not a part of the physical world. They both make the same mistake, they refuse to take consciousness on its own terms as a biological phenomenon like digestion, or photosynthesis, or mitosis, or miosis, or any other biological phenomenon.
Part of what Searle says in his first response is importantly correct. Since the distinction between illusion and reality presupposes the reality of consciousness, it makes no sense to suppose that consciousness might be an illusion, let alone assert such a monstrous thesis. It amazes me that there are people who are not persuaded by such luminous and straightforward reasoning. But pace Searle it does not follow that consciousness is a biological phenomenon. If biological phenomena are those phenomena that are in principle exhaustively intelligible in terms of the science of biology, then I don't see how consciousness could be biological even if it is found only in biologically alive beings. Can the what-it-is-like feature be accounted for in purely biological terms? (That's a rhetorical question.) And that's just for starters.
In the second response, Searle claims that consciousness is a biological property and that this ought to be "screamingly obvious" to anyone with "any education." Come on, John! Do you really want to suggest that the philosophical problem of consciousness as this is rigorously formulated by people like Colin McGinn is easily solved just be getting one's empirical facts straight? Do you really mean to imply that people who do not agree with your philosophy of mind are ignorant of plain biological facts? If consciousness were a biological phenomenon just like digestion or photosynthesis or mitosis or meiosis, then consciousness would be as unproblematic as the foregoing. It isn't.
Why is it that there is a philosophical problem of consciousness, but no philosophical problem of digestion? Note the obvious difference between the following two questions. Q1: How is consciousness possible given that it really exists, arises in the brain, but is inexplicable in terms of what we know and can expect to know about animal and human brains? Q2: How is digestion possible given that it really exists, takes place in the stomach and its 'peripherals,' but is inexplicable in terms of what we know and can know about animal and human gastrointestinal systems?
Obviously, there is a philosophical problem about consciousness but no philosophical problem about digestion. And note that even if some philosopher argues that there is no genuine philosophical problem about consciousness, because one has, say, been bewitched by language, or has fallen afoul of some such draconian principle as the Verifiability Criterion of Cognitive Meaningfulness, no philosopher would dream of arguing that there is no genuine philosophical problem of digestion. It needs no arguing. For whether or not there is a genuine problem about consciousness, there is a putative problem about it. But there is not even a putative philosophical problem about digestion. The only problems concerning digestion are those that can be solved by taking an antacid or by consulting a gastroenterologist or by doing more empirical gut science.
This is why it is at least possible with a modicum of sense to argue that the philosophy of mind collapses into the neuroscience of the brain, but impossible sensibly to argue that the the philosophy of digestion collapses into gastroenterology or that the philosophy of blood filtering and detoxification collapses into hepatology. There is no philosophy of digestion or philosophy of blood filtering and detoxification.
It is obviously not obvious that consciousness is a biological phenomenon. Searle is brilliant when it comes to exposing the faults of other theories of mind, but he is oblivious to the problems with his own. Searle 'knows' in his gut that naturalism just has to be true, which is why he cannot for a second take seriously any suggestion that consciousness might have a higher origin. But he ought to admit that his comparison of consciousness to digestion and photosynthesis and mitosis and meiosis is completely bogus. He can still be a naturalist, however, either by pinning his hopes on some presently incoceivable future science or by going mysterian in the manner of McGinn.
More on Searle in my appropriately appellated Searle category.
In Does Matter Think? I wrote:
I now add that I am using 'thinking' in the broad Cartesian sense that covers all intentional or object-directed experiences; but I also hold that non-intentional experiences are unintelligible to us on the basis of current physics. My thesis is that, given what we know about the physical world from current physics, it it unintelligible that the phenomena of mind, whether intentional or non-intentional, be wholly material in nature.
I grant that what is unintelligible to us might nevertheless be the case. But if such-and-such is unintelligible to us, then that is a fairly good reason to believe that it is not possibly the case. A theological example may help clarify the dialectical situation. Christians believe that God became man. Some will say that this is impossible in the strongest possible sense: logically impossible, i.e., in contravention of the Law of Non-Contradiction. For what the doctrine implies is that one person has both human and divine attributes, that one person is both passible and impassible, omniscient and non-omnisicent, etc. One response, a mysterian response, is to say that the doctrine of the Incarnation is true, and that therefore it is logically possible. The fact, if it is fact, that the Incarnation is unintelligible to us — where 'unintelligible' means: not understandable as possibly true in a broadly logical sense – does not show that the doctrine is impossible, but that it is a mystery: a true proposition that we, due to our limitations, cannot understand.
A materialist can make the same sort of move in one of two ways. He could say that our understanding of matter at present does not allow us to understand how conscious experience could be wholly material in nature, or he can say that our understanding of matter will never allow us to understand how conscious experience could be wholly material in nature. Either way, conscious experience, whether intentional or non-intentional, is wholly material in nature, and falls entirely within the subject-matter of physics, whether a future physics achievable by us, or a physics which, though not achievable by us, is perhaps achievable by organisms of a different constitution who study us.
If I understand Galen Strawson's view, it is the first. Conscious experience is fully real but wholly material in nature despite the fact that on current physics we cannot account for its reality: we cannot understand how it is possible. Here is a characteristic passage from Strawson:
Strawson and I agree on two important points. One is that what he calls experiential phenomena are as real as anything and cannot be eliminated or reduced to anything non-experiential. The other is that there is no accounting for experiential items in terms of current physics.
In the Comments Vlastimil V. asked:
It is matter as understood by current physics. And yes, one can know a priori that matter so conceived cannot think or feel. Note that I am not saying that matter anyhow conceived can be known a priori to be such that it cannot think or feel. I admit the very vague, very abstract, epistemic (and perhaps only epistemic) possibility that God or some super-intelligent extraterrestrial or even human being far in the future could get to the point of understanding how an experiential item like a twinge of pain could be purely material or purely physical. But this is really nothing more than an empty gesturing towards a 'possibility' that cannot be described except in the vaguest terms. It is nothing but faith, hope, and hand-waving.
An experiential item such as a twinge of pain or a rush of elation is essentially subjective; it is something whose appearing just is its reality. For qualia, esse = percipi. If I am told that someday items like this will be exhaustively understood from a third-person point of view as objects of physics, I have no idea what this means. The notion strikes me as absurd. We are being told in effect that what is essentially subjective will one day be exhaustively understood as both essentially subjective and wholly objective. If you tell me that understanding in physics need not be objectifying understanding, I don't know what that means either.
As Strawson clearly appreciates, one cannot reduce a twinge of pain to a pattern of neuron firings, for such a reduction eliminates the what-it-is-like-ness of the experience. And so he inflates the concept of the physical to cover both the physical and the irreducibly mental. But by doing this he drains the physical of definite meaning. His materialism is a vacuous materialism.
Strawson frankly confesses, "I am by faith a materialist." (p. 69) Given this faith, experiential items, precisely as experiential, must be wholly material in nature. This faith engenders the hope that future science will unlock the secret. Strawson must pin his hope on future science because of his clear recognition that experiential items are incomprehensible in terms of current physics.
But what do faith and hope have to do with sober inquiry? It doesn't strike me as particularly intellectually honest to insist that materialism just has to be true and to uphold it by widening the concept of the physical to embrace what is irreducibly mental. It would be more honest just to admit that the mind-body problem is insoluble.