In the previous post (Part I), we met some aliens that seem to have developed a turbo-charged neuroscientific theory of consciousness. Unfortunately for the materialist, the aliens’ story seems incomplete in a way that the antimaterialist can exploit as follows:
While impressive, the aliens’ story leaves out the most essential aspect of consciousness: subjective experience. They make no mention of the fact that there is something it is like for the cats to be smonscious. From the standpoint of the alien theory of brain function, subjective experiences constitute an additional unpredicted fact about the cats. But we know that experiences exist, so any theory that leaves them out is incomplete.
Put bluntly, instead of constructing a theory of consciousness, the aliens stand in complete ignorance of its existence. This is no subtle shortcoming.
Materialists will try to neutralize this concern by claiming that subjectivity is identical to smonsciousness, that these are merely two ways of conceiving of the same property. That is, the alien story highlights a conceptual gap between brains and experiences, but does nothing to support the antimaterialist metaphysical position.
While this standard ‘two concepts/one property’ move technically preserves the logical possibility of materialism, to say the alien story does no harm against materialism verges on disingenuous. In that inductive space of what is reasonable and probable, rather than merely logically possible, materialism takes a serious hit when it runs into our alien friends. Materialists should be deeply dissatisfied that someone could have a complete understanding of the cat’s brain yet be ignorant of consciousness.
Especially given their default tendency to fetishize the natural sciences, materialists should be troubled that they are forced into a position with no clear precedent in the natural sciences. In that context, their response smacks of special pleading, an ad hoc reaction to an obvious shortcoming rather than the organic outgrowth of a positive naturalistic theory.
The materialists might counter by saying that such scenarios actually have many analogous precedents in the natural sciences. Scientists often study the higher-level feature of a system (e.g., heat/patterns of inheritance) and then only later discover its lower-level basis (e.g., mean kinetic energy/genes). The aliens could be implementing the converse scenario, studying the lower-level details of cat brains, but not examining the higher-level (conscious) features. This would be like studying the individual particles in a gas without ever coming to know the higher-level statistical property we know as temperature. This is epistemically interesting, but carries no obvious metaphysical punch.
Unfortunately, by hypothesis the aliens have complete knowledge of cat brains at every level of organization, so this ‘levels defense’ fails. The most apt analogies are actually damning to materialism. Saying our aliens have left nothing out is like saying a physicist has given a complete account of Mercury’s orbit even though he doesn’t know what it means for a planet to revolve around a star; or that a botanist can know everything about plant reproduction even if he has no idea what pollen is. In such cases, the researcher’s story patently overlooks an essential ingredient. The burden of proof would clearly be on the advocate of the physicist/botanist to show that the primae facie appearance of metaphysical incompleteness is mistaken (e.g., that it is merely conceptual). The same applies for our alien scenario.
Our vituperative antimaterialist makes some interesting points. Some are true, some questionable. How should the materialist respond? This post is already too long, so I will defer posting Part III for a couple of weeks [ahem–make that a year].
Note: This scenario was inspired partly by Sellars’ historical fiction involving ‘our Rylean Ancestors’ in his Empiricism and the Philosophy of Mind (1956). [Note added 9/4/12: More obviously it is influenced by the usual suspects (Chalmers, Jackson, Levine, and others who have pushed on the apparent gap between knowledge of brains and first-hand knowledge of experiences).]
I suggest that “knowledge” requires subjectivity. Therefore if aliens “know” that the cat is smonscious, then they also know (or guess) that it is conscious, based on their own experience.
That sort of is cheating. If you have trouble with unconscious scientists, I would suggest thinking of them as a community of radical behaviorists who decide to study brains.
What if at some point acknowledging that cats instantiate a ‘viewpoint’ on the world is necessary to fully grasp their behavior, and what if such a ‘viewpoint’ notion can only be understood in reference to one’s own viewpoint? I don’t know if we’re departing from materialism here but I think that such a notion of viewpoint could be a sufficient account of ‘what it is like’.
Quen_tin I am very sympathetic to this, and think that part of the “smonsicous” representational system is that it involves a “perspectival” picture of reality (this is what I was getting at when I mentioned the smonscious system as building a representation of nearby events (in space) happening now (in time)). This is something Arnold Trehub has written a lot about and I think there is something right there.
The problem is, by hypothesis the aliens understand this perspectival representational system very well, but (arguing for the time being as an antimaterialist) at a conceptual level this is still not enough to get you to the conclusion that this special representational system is conscious, that there is something it is like to instantiate such a system.
Certainly the aliens see that smonsciousness is special, in some ways quite central to the cats’ cognitive life, decision-making, and such. And they could even talk about what it is like for the cat to be smonscious. This would be in the same sense that they can talk about what it is like for them (the aliens) to experience X. In this case ‘what it is like’ means ‘What effects, within my cognitive architecture, does X produce’. Based on that they could say that when the cat sees green, for the cat it is subjectively (i.e., within its cognitive architecture) like when it sees yellow.
In that sense, we can get the aliens to a way of talking that is, on the surface, nearly identical to our way of talking about experiences in terms of ‘what it is like.’ This is something I have pursued in my notes on Part III, in fact, but I
am not sure it made it past the cutting room floor as it ultimately
seemed too much like a semantic magic trick rather than getting at the core issues.
Eric: “The problem is, by hypothesis the aliens understand this perspectival representational system very well, but (arguing for the time being as an antimaterialist) at a conceptual level this is still not enough to get you to the conclusion that this special representational system is conscious, that there is something it is like to instantiate such a system.”
*THE ONE QUALE THAT RULES ALL QUALIA*
I claim that when such a representational system is activated (e.g., activation of retinoid space) there IS something that it is like for the system, namely *something somewhere* in spatio-temporal relation to its neuronal locus of perspectival origin — what I call the core self (I!). This is subjectivity. I argue that there are no qualia without the phenomenal component (quale) of something being represented somewhere with respect to the core self. Any brain representation having this particular property is a conscious representation.
If the anti-materialist asks why do we need to propose such a brain mechanism, the only proper answer, it seems to me, is that it enables us to explain and predict conscious phenomena within the norms of science rather than just describe such phenomena as they occur.
Let’s say this is exactly what the aliens discover as the smonscious representational system, Arnold.
The antimaterialist in my scenario won’t ask why we need it: the aliens discovered it, and it is by hypothesis something real in the brain. The problem is that the aliens only have access to one side of the bridge, the neural side. They don’t have access to experience itself, so never develop the concept of phenomenal subjectivity in that sense. From their perspective, there is nothing missing, no two sets of concepts to be bridged, because they simply lack one of the land masses that (for people) is connected by these bridge-hypotheses such as ‘Experience X is neural process Y’.
This is what makes this scenario harder than Mary, who already has the other land mass, just missing a township here and there, but the strategy for her, of hypothesizing that neural process X is subjective, is unproblematic.
Richard suggested three papers that might be relevant for my reductio argument against materialism. My impressions of each:
A. Derek Ball’s ‘There are no phenomenal concepts’
I feel like I am smarter having read this paper. Well written, well researched. Unfortunately the ‘deference’ strategy will not work for my aliens, as they have no aliens to defer to, and are studying cats that also don’t have phemonenal concepts.
He tries to address this concern with ‘Lonely Mary’ (page 22). But she has the concept of phenomenal consciousness, so for her it is a matter of filling in “missing shades” (modalities). I agree, and this is how I deal with Mary too, but this is why I built the aliens as lacking experience altogether, and the conception of experience. They don’t have this way of cheating. This is one of the knobs I turned specifically to make a scenario tougher for the materialist.
B. Blocks ‘Harder Problem’
While Block stages the Hard Problem solution in terms of the ‘two concepts/one property’ schema I attacked in Part II, beyond that I cannot find what is supposed to be relevant, though I admit I didn’t read it closely to the end. I found the discussion of multiple realizability of consciousness anachronistic and unconvincing, frankly, so got hung up on that and didn’t really follow exactly what the harder problem is supposed to be.
C. Geoffrey Lee’s paper ‘Alien subjectivity and the importance of conciousness’
This also seems somewhat orthogonal to the issues here, though he does talk about a Martian species of scientists that lacks subjectivity (which I find reassuring). Contrary to my scenario he seems to think they wouldn’t find a natural division of the brain into conscious versus nonconscious processes (or in my case, smonscious/unsmonscious).
This seems odd, given all the evidence we already have for obvious neural differences, even this young in our study of brains. This is actually pretty important for his overall project, but it seems just empirically suspect, and directly contradicts how I see brain research going presently and (predict it to go) in the future.
At any rate I can just say my scenario assumes deflationary physicalism is false. This would again be an instance of turning a knob to make it tough for materialist, and see if we can respond. This would be a powerful strategy, as if we can respond strongly to this worst-case scenario, it cuts down many antimaterialist trees with one sweep of the ax.
Eric; “While impressive, the aliens’ story leaves out the most essential aspect of consciousness: subjective experience. They make no mention of the fact that there is something it is like for the cats to be smonscious. From the standpoint of the alien theory of brain function, subjective experiences constitute an additional unpredicted fact about the cats. But we know that experiences exist, so any theory that leaves them out is incomplete.”
Suppose your aliens had access to humans and discovered everything that there is to know about about the human brain including the smonscious system of brain mechanisms. By stipulation, since they are non-conscious creatures, they have no inkling that “smonsciousness” is what we call “consciousness” and that what they describe is, indeed, subjectivity. Why can’t we, as conscious human beings, simply thank the alien scientists for advancing our knowledge of consciousness. The metaphysics of consciousness is in our realm not in this alien realm. What are the counter-arguments?
This is why I had them study cats, not humans. To make it tougher for the materialist so they couldn’t parasitize our concepts about subjectivity. I am not arguing that it is impossible for them to acquire the requisite concepts (that is a more tricky argument I’m not sure of the right answer but they probably can).
The fact that they cannot learn that cats are subjectively glowing with consciousness (or whatever your favorite metaphor is) by studying brains should be a major concern to the materialist. If they have to study a species that is not only conscious, but knows they are conscious (and hence supplies the concept toward which neuroscience bridges), this shouldn’t assuage the dissatisfaction.
Eric, can you give an example of what you mean by “deflationary materialism”?
It’s the topic of this paper:
By my understanding it is the view that there is no unique signature of conscious processing in brains to differentiate it from nonconscious processing (close relative of Dennett’s ‘no Cartesian theatre’ slogan).
Eric: “The fact that they [unconscious aliens] cannot learn that cats are subjectively glowing with consciousness (or whatever your favorite metaphor is) by studying brains should be a major concern to the materialist.”
I’m having trouble understanding why this should be a problem for the materialist. The alien scientist knows all about the brain of a cat from the 3rd-person perspective only, with no possibility of bridging the smonscioiusness state to some kind of conscious state. The enlightened materialist expects this to be the case because the unconscious alien is missing all aspects of a 1st-person perspective and has only the objective domain of biophysical description as a ground of logical and analogical inference. The human materialist, on the other hand, has both the objective and subjective domains of description to work with as grounds of inference bridging brain events (3pp) to conscious events (1pp).
But the first-person subjective perspective is real, no? It is a real property of that cat. If materialism is true, then the aliens should know about it. I’m not saying they should have the cat’s experience of hearing a mouse or whatever (any more than someone studying photosynthesis should photosynthesize). But that they don’t even know that there is any subjectivity there should be a concern if the material facts exhaust all the facts about the cats (which under materialism they should). There is this additional property hanging out there hiding from the materialistic aliens.
1. To have COMPLETE physical knowledge of a conscious brain the scientist needs to study the brain both from the outside (3pp) AND from the inside (1pp).
2. The non-conscious alien scientist is able to study the conscious brain only from the outside (3pp). Therefore the alien scientist cannot have COMPLETE physical knowledge of a conscious brain, even though you stipulate that he does.
Eric: “There is this additional property hanging out there hiding from the materialistic aliens.”
Yes, it is hidden from those who cannot study the brain from the inside — no first-person perspective on the brain. If you concede that this additional property is physical, then you must acknowledge that the alien does NOT have complete physical knowledge of the conscious brain. If you propose that this additional property is NOT physical, then you are endorsing some kind of dualism.
But why are brains different from plants or rocks? Do we need a 1pp on them to have complete physical knowledge? What you are proposing is that what counts as physical knowledge would need to be expanded to include conscious experiences from 1pp. That seems like building in dualism but calling it physicalism.
If materialism is true, nothing (ontologically) should be hidden from the materialistic aliens.
I agree with Eric. Besides 1pp and 3pp are not physical concepts, or I don’t see how 1pp is supposed to be derived from a mathematical model without an ad hoc supplement. I don’t see either, given that the cat’s brain is different from a human brain, how human materialists are supposed to map specific qualitative aspects with brain structures if not again through an ad hoc supplement to the physical model.
Eric Thomson wrote:
“But why are brains different from plants or rocks? Do we need a 1pp on them to have complete physical knowledge?”
Brains have neuronal mechanisms; plants and rocks do not. Also, we have no evidence that plants and rocks are conscious, so we don’t need to know what it is like (1pp) for them. The 3rd-person perspective is all that is needed.
Eric: “What you are proposing is that what counts as physical knowledge would need to be expanded to include conscious experiences from 1pp. That seems like building in dualism but calling it physicalism.”
Yes, conscious experiences are physical processes. But this is just the opposite of building in dualism which claims that consciousness cannot be physical.
In the case of understanding consciousness within scientific norms, the problem is to reconcile the 3pp domain of description with the 1pp domain of description by an appropriate bridging principle. For example, see here:
But the aliens are missing out on the fact that a bridge is even needed. For them, nothing is left out, they have a complete story. Nothing to bridge. In fact, this is another way to state the problem, and a good time to point out how erecting unique principles just for consciousness smacks of special pleading rather than an organic outgrowth of the science. For the aliens, there is no reason to treat cats’ brains as deserving of special treatment (compared with other biological processes like photosynthesis).
To import our perspective into the discussion is fine, if it lets us explain what is going on in a way that seems uncontrived and reasonable. This is what my response involves (though I am not all that happy with it: I think this will simply stand as a reasonable objection to materialism, frankly, but one that materialists can also be reasonable in rejecting).
Eric: “For the aliens, there is no reason to treat cats’ brains as deserving of special treatment (compared with other biological processes like photosynthesis).”
Of course. This is true because the aliens have no concept of a conscious brain vs. a non-conscious brain.
Eric: “To import our perspective into the discussion is fine, if it lets us explain what is going on in a way that seems uncontrived and reasonable.”
Fine. No argument about this. But I don’t see how a dispute about phenomenal consciousness between an anti-physicalist and a physicalist can possibly be resolved unless both agree on a working definition of phenomenal consciousness.
I have had a running argument with Stevan Harnad about this for years. Here’s part of a recent exchange from the Montreal Forum on Turing Consciousness:
Arnold Trehub23 July 2012 08:17
THE RETINOID THEORY IS A CAUSAL EXPLANATION OF HOW AND WHY WE FEEL (have conscious experience)
Stevan: “A scientific theory gives a testable causal explanation of the evidence.”
Consider the following:
1. I am conscious if and only if I have a *sense of being here with something all around me even though the particulars are constantly changing*. Call this the minimal conscious content (MCC).
2. MCC must be the product of an active brain. Given this stipulation, I have proposed, as a working definition, that consciousness (MCC) is a transparent brain representation of the world (the space that is all around me) from a privileged egocentric perspective (me here).
1. What system of mechanisms in the brain has the competence to cause MCC? I have proposed that the human brain has a system of neuronal brain mechanisms with the structure and dynamics that can represent a global volumetric spatiotopic analog of the world space we live in, including a fixed locus of perspectival origin that I call the *core self* (I!). This part of the retinoid system is called RETINOID SPACE. I have specified the minimal structure and dynamics of the brain system that regulates the content of retinoid space and call it the RETINOID SYSTEM.
2. Why should we think that the retinoid system is a competent causal model of MCC? It seems clear that any competent model should be able to make relevant predictions that can be tested and are empirically validated. One thing we should NOT expect is that a competent causal model must be able to exhibit ALL the properties of MCC. (I think this unwarranted expectation plays a part in the “explanatory gap” notion in consciousness studies.) What we should expect is that the candidate model of MCC be able to generate matching *analogs* of relevant properties of the phenomena.
3. In a wide range of empirical tests, the operating characteristics of the retinoid model successfully predicted/explained previously inexplicable conscious phenomena/feelings, and also successfully predicted novel conscious phenomena…[examples given].
Eric, what is the rejoin
Will reply outside this narrow confine, pop!
I wrote: “For the aliens, there is no reason to treat cats’ brains as deserving of special treatment (compared with other biological processes like photosynthesis).”
Arnold replied: “Of course. This is true because the aliens have no concept of a conscious brain vs. a non-conscious brain.”
This is enough to generate concern for materialism. That we have to align our “special” first person perspective with the findings of the materialistic story, that we have to provide a “bridge” between these two worlds, when there is supposed to be just one world, is the problem. Or rather, the problem is that they are completely ignorant of the subjective side of the equation, despite being materialistically omniscient.
This isn’t a matter of defining phenomenal consciousnes (I think we agree that it is subjective glow of experience or whatever). The kernel argument is:
a) The property of being phenomenally consciousness exists.
b) The materialistic story from the aliens does not attribute this property to cats.
c) Therefore, the materialistic story is incomplete.
The question is whether the materialistic story is incomplete in an interesting, or predictable and metaphysically uninteresting, way.
So the details of retinex, smonsciousness aren’t all that important.
Let’s say your favorite neural theory is right, that it predicts human
phenomenology perfectly, which you already have a “first person”
understanding of. How does that help you deal with a-c above?
Eric: “The question is whether the materialistic story is incomplete in an interesting, or predictable and metaphysically uninteresting, way.”
It seems to me that the incomplete story told by the non-conscious materialist alien is both predictable and interesting, taken in context, because it demonstrates that only a conscious scientist can have knowledge of and explain the existence of phenomenal consciousness as a natural part of the physical world.
The point is that your claim that the non-conscious aliens are materially/physically omniscient is untenable because they are ignorant of the fact consciousness is a real part of the physical world.
“your claim that the non-conscious aliens are materially/physically
omniscient is untenable because they are ignorant of the fact
consciousness is a real part of the physical world.
So we get back to my previous concern, that it seems you want to expand the ‘physical’ to include a special new property: consciousness. This looks like dualism to me. Consciousness is not part of physics. By all our best evidence, it is a system-level property of certain types of brains. The aliens should have no more trouble discovering it than we have trouble discovering system-level properties of digestive systems.
Given that, the key is whether they have actually described consciousness without knowing it, whether they have actually discovered and characterized conscious experience in a way that leaves nothing out metaphysically (only conceptually). That seems the only way out for the materialist who takes the scenario seriously to begin with (this is the two concepts/one property strategy I attacked in Part II precisely because it seems the only reasonable option for the materialist).
Eric: “So we get back to my previous concern, that it seems you want to expand the ‘physical’ to include a special new property: consciousness.”
Consciousness is no more a special new property of the physical than the mammalian eye is a special new property of the physical. Both appeared in the normal course of biological evolution. A blind alien scientist with no concept of vision might know all about the structure and dynamics of the eye but would not fully understand its visual function.
Eric: “This looks like dualism to me. Consciousness is not part of physics.”
This is not dualism. It is dual-aspect physical monism. Here’s what I wrote at the end of my paper Where Am I? Redux:
“Further reflection on the role of the retinoid system as a successful explanatory model for these and other empirical findings (Trehub, 1991, 2007) leads to the conclusion that neuronal activity within the brainʼs retinoid mechanisms and the content of phenomenal consciousness are dual aspects of the same underlying reality (Velmans, 2009).”
Consciousness is an essential part of physics. Without consciousness, physics would not exist! The integration of what we learn about human consciousness together with our old standard models of physics is now on the agenda.
It seems to me that two criteria need to be met by any *explanatory* theory of consciousness:
1. It must account for the existence of subjectivity.
2. it must be described in a way that enables us to propose empirical tests of its theoretical implications.
Can a non-physical theory of consciousness meet these criteria?