Ian Phillips on Simple Seeing

A couple of weeks ago I attended Ian Phillips’ CogSci talk at CUNY. Things have been hectic but I wanted to get down a couple of notes before I forget.

He began by reviewing change blindness and inattentional blindness. In both of these phenomena subjects sometimes fail to recognize (or report) changes that occur right in front of their faces. These cases can be interpreted in two distinct ways. On one interpretation one is conscious only of what what is able to report on, or attend to. So if there is a doorway in the background that is flicking in and out of existence as one searches the two pictures looking for a difference and when one is asked one says that they see no difference between the two pictures one does not consciously experience the door way or its absence. This is often dubbed the ‘sparse’ view and it is interpreted as the claim that conscious perception contains a lot less detail in it than we naively assume.

Fred Dretske was a well known defender of a view on which distinguishes two components of seeing. There is what he called ‘epistemic seeing’ which, when a subject sees that p, “ascribes visually based knowledge (and so a belief) to [the subject]”. This was opposed to ‘simple seeing’ which “requires no knowledge or belief about the object seen” (all quoted material is from Phillips’ handout). This ‘simple seeing’ is phenomenally conscious but the subject fails to know that they have that conscious experience.

This debate is well known and been around for a while. In the form I am familiar with it it is a debate between first-order and higher-order theories of consciousness. If one is able to have a phenomenally conscious experience in the absence of any kind of belief about that state then the higher-order thought theory on which consciousness requires a kind of higher-order cognitive state about the first-order state for conscious perception to occur, is false. The response developed by Rosenthal, and that I find pretty plausible, is that in change blindness cases the subject may be consciously experiencing the changing element but not conceptualize it as the thing which is changing. This, to me, is just a higher-order version of the kinds of claims that Dretske is making, which is to say that this is not a ‘sparse’ view. Conscious perception can be as rich and detailed as one likes and this does not require ‘simple seeing’. Of course, the higher-order view is also compatible with the claim that conscious experience is sparse but that is another story.

At any rate, Phillips was not concerned with this debate. He was more concerned with the arguments that Dretske gave for simple seeing. He went through three of Dretske’s arguments and argued that each one had an easy rejoinder from the sparse camp (or the higher-order camp). The first he called ‘conditions’ and involved the claim that when someone looks at a (say) picture for 3-5 minutes scanning every detail to see if there is any difference between the two, we would ordinarily say that they have seen everything in the two pictures. I mean, they were looking right at it and their eyes are not defective! The problem with this line of argument is that it does not rule out the claim that they unconsciously saw the objects in question. The next argument, from blocking, meets the same objection. Dretske claims that if you are looking for your friend and no-one  is standing in front of them blocking them from your sight, then we can say that you did see your friend even if you deny it. The third argument involved that when searching the crowd for your friend you did saw no-one was naked. But this meets a similar objection to the previous two arguments. One could easily not have (consciously) seen one’s friend and just inferred that since you didn’t see anyone naked your friend was naked as well.

Phillips then when on to offer a different way of interpreting simple seeing based on signal detection theory. The basic intuition for simple seeing, as Phillips sees it, lies in the idea that the visual system delivers information to us and then there is what we do with the information. The basic metaphor was a letter being delivered. The delivery of the letter (the placing of it into the mailbox) is one thing, you getting the letter and understanding the contents, is another. Simple seeing can then be thought of as the informative part and the cognitive noticing, attending, higher-order thought, etc, can be thought of as a second independent stage. Signal detection theory, on his view, offers a way to capture this distinction.

Signal detection theory starts with treating the subject as an information channel. They then go on to quantify this, usually by having the subject perform a yes/no task and then looking at how many times they got it right (hits) versus how many times the got it wrong (false alarms). False alarms, specifically, involve the subject saying the see something but being wrong about it, because there was no visual stimulus. This is distinguished from ‘misses’ where there was a target but the subject did not report it. The ‘sensitivity to the world’ is called d’, pronounced “d prime”. On top of this there is another value which is computed called ‘c’. c, for criterion, is thought of as measuring a bias in the subjects response and is typically computed from the average of hits versus false alarms. One can think of the criterion as giving you a sense of how ‘liberal’ or ‘conservative’ the subjects’ response is. If they will say they saw something all the time then the seeming have a very liberal criterion for determine whether they saw something (that is to say they are biased towards saying ‘yes I saw it’ and is presumably mistaking noise for a signal). If they never say the say it then they are very conservative (they are biased towards saying ‘no I didn’t see it). This gives us a sense of how much of the noise in the system the subject treats as actually carrying information.

The suggestion made by Phillips was that this distinction could be used to save Dretske’s view if one took d’ to track simple seeing and c to track they subjects knowledge. He then went on to talk about empirical cases. The first involved memory across saccades and came from Hollingworth and Henderson, Accurate Visual Memory for Previously Attended Objects in Natural Scenes, the second f rom Mitroff and Levin Nothing Compares 2 Views: Change Blindness can occur despite preserved access to the changed information, and the third Ward and Scholl Inattentional blindness reflects limitation on perception, not memory. Each of these can be taken to suggest that there is “evidence of significant underlying sensitivity in [change blindness] and [inattentional blindness],”.

He concluded by talking about blindsight as a possible objection. Dretske wanted to avoid treating blindsight as a case of simple seeing (that is of there being phenomenal consciousness that the subject was unaware (in any cognitive sense) of having). Dretske proposed that what was missing was the availability of the relevant information to act as a justifying reason for their actions. He then went on to suggest various responses to this line of argument. Perhaps blindsight subjects who do not act on the relevant information (say by not grabbing the glass of water in the area of their scotoma) are having the relevant visual experience but are simply unwilling to move (how would we distinguish this from their not having the relevant visual experience)? Perhaps blindsight patients can be thought of as adjusting their criterion and so as choosing the interval with the strongest response and if so this can be thought of as reason responsive. Finally, perhaps, even though they are guessing, they really can be thought of as knowing that the stimulus is there?

In discussion afterwards I asked whether he though this line of argument was susceptible o the same criticism he had leveled against Dretske’s original arguments. One could interpret d’ as tracking conscious visual processing that the subject doesn’t know about, or one could interpret it as tracking the amount of information represented by the subjects mental states independently of what the subject was consciously experiencing (at leas to some extent). So, one might think, the d’ is good so the subject represents information about the stimulus that is able to guide its behavior, but that may be going on while the subject is conscious of some of it but not all of it, or different aspects of it, etc. So there is no real reason to think of d’ as tracking simple (i.e. unconceptualized, unnoticed, uncategorized, etc) content that is conscious as opposed to non-conscious. He responded that he did not think that this constituted an argument. Rather he was trying to offer a model that captured what he took to be Dretske’s basic intuition, which was that there was the information represented by the visual system, which was conscious, and then there was the way that we were aware of that information. This view was sometimes cast as unscientific and he thought of the signal detection material as proving a framework that, if interpreted in the way he suggested, could capture, and thus make scientifically acceptable, something like what Dretske (and other first-order theorists) want.

There was a lot of good discussion, a lot of which I don’t remember, but I do remember Ned Block asking about Phillips’ response to cases like the famous Dretske example of a wall, painted a certain color, having a piece of wallpaper in one spot. The little square of wallpaper has been painted and so is the same color as the wall. If one is looking at the wall and doesn’t see that there is a piece of wallpaper there, does one see (in the simple seeing kind of way) the wallpaper? Phillips seemed to be saying we did (but didn’t know it) and Block asked whether it wasn’t the case that when we se something we represent it visually and Phillips responded by saying that on the kind of view he was suggesting that wasn’t the case. Block didn’t follow up and didn’t come out after so I didn’t get the chance to follow up on that interesting change.

Afterwards I pressed him on the issue I raised. I wondered what he thought about the kinds of cases, discussed by Hakwan Lau (and myself) where the d’ is matched but subjects give differing answers to questions like ‘how confident are you that you saw it?’ or ‘rate the visibility of the thing seen’. In those cases we have, due to matched d’, the same information content (worldly sensitivity) and yet one subject says they are guessing while the other says they are confident they saw it (or rates its visibility lower while the other rates it higher (so as more visible)). Taking this seriously seems to suggest that there is a difference in what it is like for these subjects (a difference in phenomenal consciousness) while there is no difference in what they represent about the world (so at the first-order level). The difference in what it is like for them seems to track the way in which they are aware of the first-order information (as tracked by their visibility/confidence ratings). If so then this suggests that d’ doesn’t track phenomenal consciousness. Phillips responded by suggesting that there may be a way to talk about simple seeing involving differences in what it is like for the subject but didn’t elaborate.

I still am not sure how he responds to the argument Hakwan and I have given. If there is differing conscious experience with the same first-order states each in each case then the difference in conscious experience can only be captured (or is best captured) by some kind of difference in our (higher-order) awareness of those first-order states.

In addition, now that I have thought about it a bit, I wonder how he would respond to Hakwan’s argument (more stemming from his own version of higher-order thought theory) that the setting of the criterion in Phillips’ appeal to it in blindsight cases, depends on a higher-order process and so amounts to a cognitive state having a constitutive role in determining how the first-order state is experienced. This suggests that an ‘austere’ notion of simple seeing where there is no cognitive states involved in phenomenal consciousness is harder to find than Phillips originally thought.

The Biological Chinese Room (?)

I am getting ready to head out to New York Medical College to give Grand Rounds in the department of Psychiatry and Behavioral Sciences on the Neurobiology of Consciousness. I am leaving in just a bit but as I was getting ready I had a strange thought about Searle’s Chinese Room argument that I thought I would jot down very quickly. I assume we are all familiar with the traditional version of the argument. We have you (or Seattle) locked in a room receiving input in a foreign language and looking up proper responses in a giant rule book to return the proper output. In effect the person in the room is performing the job that a computer would taking syntactic representations and transforming them according to formally specified rules. The general idea is that since Searle doesn’t thereby understand Chinese that there must be more to understanding it than formal computation.

Now, I don’t want to get bogged down in going over the myriads of responses and counter responses that have appeared since  Seattle first gave this argument but it did occur to me that we could give a biological version of this that would target the biological nature of consciousness that Searle prefers. Indeed, I think it also would work against Block’s recent claim that some kind of analog computation suffices for phenomenal consciousness (see his talk at Google (and especially the questions at the end)). So the basic idea is this. Instead of having the person in the room implement formal computations, have them implement analog ones by playing the role of neurons. They would be sequestered in the room as usual and would receive input in the form of neurotransmitters. They would then respond with the appropriate neurotransmitters. We can imagine the entire room is hooked up in such a way that the Chinese speaker on the outside in speaking normally, or typing or whatever, and this gets translated into neural-chemical activity which is what the person in the room receives. They respond in kind and this gets translated into speech on the other end. Seattle still wouldn’t understand Chinese.

So it seems that either this refutes the biological view of consciousness or it suggests what is wrong with the original Chinese Room argument…any thoughts?

Cognitive Prosthetics and Mind Uploading

I am on record (in this old episode of Spacetime Mind where we talk to Eric Schwitzgebel) as being somewhat of a skeptic about mind uploading and artificial consciousness generally (especially for a priori reasons) but I also think this is largely an empirical matter (see this old draft of a paper that I never developed). So even though I am willing to be convinced I still have some non-minimal credence in the biological nature of consciousness and the mind generally, though in all honesty it is not as non-minimal as it used to be.

Those who are optimistic about mind uploading have often appealed to partial uploading as a practical convincing case. This point is made especially clearly by David Chalmers in his paper The Singularity: A Philosophical Analysis (a selection of which is reprinted as ‘Mind uploading: A Philosophical Analysis),

At the very least, it seems very likely that partial uploading will convince most people that uploading preserves consciousness. Once people are confronted with friends and family who have undergone limited partial uploading and are behaving normally, few people will seriously think that they lack consciousness. And gradual extensions to full uploading will convince most people that these systems are conscious at well. Of course it remains at least a logical possibility that this process will gradually or suddenly turn everyone into zombies. But once we are confronted with partial uploads, that hypothesis will seem akin to the hypothesis that people of different ethnicities or genders are zombies.

What is partial uploading? Uploading in general is never very well defined (that I know of) but it is often taken to involve in some way producing a functional isomorph to the human brain. Thus partial uploading would be the partial production of a functional isomorph to the human brain. In particular we would have to reproduce the function of the relevant neuron(s).

At this point we are not really able to do any kind of uploading as Chalmers’ or others describe but there are people who seem to be doing things that look like a bit like partial uploading. First one might think of cochlear implants. What we can do now is impressive but it doesn’t look like uploading in any significant way. We have computers analyze incoming sound waves and then stimulate the auditory nerves in (what we hope) are appropriate ways. Even leaving aside the fact that subjects seem to report a phenomenological difference, and leaving aside how useful this is for a certain kind of auditory deficit, it is not clear that the role of the computational device has anything to do with constituting the conscious experience, or of being part of the subject’s mind. It looks to me like these are akin to fancy glasses. They causally interact with the systems that produce consciousness but do not show that the mind can be replaced by a silicon computer.

The case of the artificial hippocampus gives us another nice test case. While still in its early development it certainly seems like it is a real possibility that the next generation of people with memory problems may have neural prosthetics as an option (there is even a startup trying to make it happen and here is a nice video of Theodore Berger presenting the main experimental work).

What we can do now is fundamentally limited by our lack of understanding about what all of the neural activity ‘means’ but even so there is impressive and suggestive evidence that homelike like a prosthetic hippocampus is possible. They record from an intact hippocampus (in rats) while performing some memory task and then have a computer analyze and predict what the output of the hippocampus would have been. When compared to actual output of hippocampal cells it is pretty good and the hope is that they can then use this to stimulate post-hippocampal neurons as they would have been if the hippocampus was intact. This has been done as proof of principle in rats (not in real time) and now in monkeys, and in real time and in the prefrontal cortex as well!

The monkey work was really interesting. They had the animal perform a task which involved viewing a picture and then waiting through a delay period. After the delay period the animal is shown many pictures and has to pick out the one it saw before (this is one version of a delayed match to sample task). While they were doing this they recorded activity of cells in the prefrontal cortex (specifically layers 2/3 and 5). When they introduced a drug into the region which was known to impair performance on this kind of task the animal’s performance was very poor (as expected) but if they stimulated the animal’s brain in the way that their computer program predicted that the deactivated region would respond (specifically they stimulated the layer 5 neurons (via the same electrode they previously used to record) in the way that the model predicted they would have been by layer 2/3) the animal’s performance returned to almost normal! Theodore Berger describes this as something like ‘putting the memory into memory for the animal’. He then shows that if you do this with an animal that has an intact brain they do better than they did before. This can be used to enhance the performance of a neuroscience-typical brain!

They say they are doing human trials but I haven’t heard anything about that. Even so this is impressive in that they use it successfully in rats for long term memory in the hippocampus and then they also use it in monkeys in the prefrontal cortex in working memory. In both cases they seem to get the same result. It starts to look like it is hard to deny that the computer is ‘forming’ the memory and transmitting it for storage. So something cognitive has been uploaded. Those sympathetic to the biological view will have to say that this is more like the cochlear implant case where we have a system causally interacting with the brain but it is the biological brain that stores the memory and recalls it and is responsible for any phenomenology or conscious experiences. It seems to me that they have to predict that in humans there will be a difference in the phenomenology that stands out to the subject (due to the silicon not being a functional isomorph) but if we get the same pattern of results for working memory in humans are we heading towards Chalmers’ acceptance scenario?

Consciousness and Category Theory

In the comments on the previous post I was alerted, by Matthias Michel, to a couple of papers that I had not yet read. The first was a paper in Neuroscience Research which came out in 2016:

And the second was a paper in Philosophy Compass that came out in March 2017:

After reading these I realized that I had heard an early version of this stuff when I was part of a plenary session with Tsuchiya in Tucson back in April of 2016. The title of his talk is the same as the title of the Philosophy Compass paper and some of the ideas are floated. I had intended writing something about this after my talk but I apparently didn’t get to it (yet?). I am in the midst of battling a potty-training toddler so it may not be anytime soon but I did want to get out a few (inchoate) reactions to these papers now that I have read them.

Both of these papers were very interesting. The first was interesting because it is the first time I have seen proponents of IIT acknowledge that they need to examine their ‘axioms’ more carefully. Are these axioms self-evident? Not to many people! Might there be alternate formulations? Yes! At the very least there should be some discussion of higher-order awareness (or awareness at all). There ideally should be an axiom like:

Awareness: Consciousness is for one. If one is in no way aware of oneself as being in a mental state then one is not consciously in that mental state

Of course they don’t want to add anything like this because as it stands the theory clearly assumes (without argument) that higher-order theories of consciousness are false. This is a problem that will not go away for IIT. But I’ll come back to that (by the way, the first ‘axiom’ of IIT sometimes seems to me to suggest a higher-order interpretation so one might assimilate this to an unpacking of the first axiom).

The central, and very interesting, idea of these papers that they are presenting is that category theory can help IIT address the hard problem (and some of the issues I raised in the previous post). There are a lot of mathematical details that are not relevant (yet) but the basic idea is that category theory lets us look at the structures that mathematical objects have and compare it to the structure of other mathematical structures. They want to exploit this by making a category out of the integrated information cause-effect space and one for quaila and then use category theory to examine how similar these two categories are.

First, can qualia form a category? They address this issue in the first paper but (to use a low hanging pun) this looks like a category mistake. Qualia are not mathematical objects. I suppose you could form the set of qualia and that would be a mathematical (i.e. abstract) object. But if you show that this structure overlaps with IIT have you shown anything about qualia themselves? Only if the structure captured in this category exhausts  the nature of qualia, but that is highly controversial! My guess is that there will be many categories that we could construct that would have some functors to both the category of qualia and the category of IIT structures. So, take the category of the set of Munsel color chips (not the experience of them, the actual chips). Won’t they stand in relations to each other that can be mapped onto the IIT domain in pretty much exactly the same way as the set of qualia!? If so, then IIT is Naive Realism? That is a joke but the point is that one would not want to claim that this shows that IIT is a theory of color chips. All we have shown is that there is a similar structure that runs in common in these two mathematical structures that at first seemed unrelated. That is interesting, but I don’t see how it can help us.

To their credit they recognize that this is a bit controversial and here is what they say about the issue:

In the narrow sense, a quale refers to a particular content of consciousness, which can be compared or characterized as a particular aspect of one moment of experience or a quale in the broad sense (Balduzzi and Tononi, 2009; Kanai and Tsuchiya, 2012). Can category theory consider any qualia we experience as objects or arrows? Some qualia in the narrow sense are straightforward to consider as objects: a quale for a particular object or its particular aspect, such as color. There are, however, some aspects of experience that are apparently difficult to consider as objects. For example, we can experience a distance between the two cups, which is a relationship between the objects but itself has no physical object form. Such abstract conscious perception can be naturally regarded as a relationship between objects: an arrow. Further, there are some types of qualia that seem to emerge out of many parts, such as a face. A whole face is perceived as something more than a collection of its constituent parts; there is something special about a whole face. Psychological and neuroscientific studies of faces point to configural processing, that is, a web of spatial relationship among the constituent parts of a face is critical in perception of a whole face (Maurer et al., 2002). In category theory, a complicated object, like a quale for a face, can be considered as an object that contains many arrows. Considered this way, any quale in the narrow sense can be considered as either an object, an arrow, or an object or arrow that contains any combinations of them.

But even if this is ok with you (and you set aside questions about whether ‘to the right of’ can be an arrow in category theory (will it obey the axiom of composition?)) what goes into the qualia category? They seem to assume that (at least some of) it is non-controversial but that isn’t so clear to me. Even so, what about Nagel’s bat? In order to use this procedure we would have to already know what kinds of qualities, conscious experiences, the bat had in order to form the category. But we have no idea what kinds of ‘objects’ and ‘arrows’ to populate that category with! That was kinda Nagel’s point!

To hammer this point home recall the logic gates that serve as simple illustrations of IIT. How are we to use this approach on it? We know what IIT says and so we can form that category without any problems. But what goes into the category of ‘qualia’ for the logic gate system’? We have no idea. In response to a question about Scott Aaronson’s objection Tsuchiya says that the expander grid may have a huge conscious field but would not have any visual experience. But what justifies this assertion?

They conclude their paper with the following remarks:

We proposed the three steps to apply the category theory approach in consciousness studies. First, we need to characterize our own phenomenological experience with detailed and structured descriptions to the extent to accept the domain of qualia as a category.

This may prove to be a difficult task and not just for the reasons having to do with higher-order awareness. Phenomenology is tricky stuff and it is notoriously hard to get people to agree on it (N.B. this is an understatement!) and since that is the case this general strategy seems doomed.

 

Another frustrating assertion with minimal evidence comes in the second paper linked to above and it has to do with the No-Report paradigm.

Noreport paradigms have implied that certain parts of the brain areas, such as the prefrontal areas, may not be related to consciousness, but more to do with the act of the reports (Koch, Massimini, Boly, & Tononi, 2016).

IF one buys this then one will see the IIT irreducible ‘concepts’ as corresponding to phenomenally conscious states but if instead one thinks that these results are overrated then one will see these irreducible IIT ‘concepts’ as picking out mental representations that may or may not be conscious. Thus we cannot extrapolate from the results of IIT until the debate with higher-order theories is resolved.

And that cannot happen until the proponents of IIT actually address the empirical case for higher-order theories. This is something that they have been very reluctant to do and when they discuss other theories of consciousness they studiously avoid any mention or discussion of higher-order theories. Higher-order theories need to be taken as seriously as Global Workspace, local re-entry, and other theories one finds in neuroscience and for the same reasons; because there is a significant (not decisive) evidence in favor of the theory.

But ok, what about the limited claim that we could in principle know whether the bat’s phenomenology was more like our seeing or our hearing? If we could generate the relevant category for the human conscious visual experience versus auditory experience and then if we could generate the IIT category for the bat’s echolocation we could compare them and see if it resembles our visual or auditory categories. According to Tsuchiya if we found that it resembled the IIT category for our auditory experiences (instead of our visual) or vice versa then we would have some evidence that they experienced the world in the same way we did.

But this seems to me to be a fundamental misunderstanding of Nagel’s point. His point was that there is no reason to expect that the bat’s experience would be anything like our seeing or our hearing. To know what it is like for the bat requires that we take up the bat’s point of view (according to Nagel). It is not clear that this addresses this issue at all! Even if we found that the bat’s brain integrated information in the way our brain integrates auditory information, and which results in the conscious experience of hearing for us, even if (stress on the IF) we discovered that why should we think that the bat’s experience was just like our experience of hearing? The point that Nagel wanted to make was that conscious experience seems somehow essentially bound up with the idea of subjectivity, of being accessible only from one’s own point of view. This is entirely missed in the proposal by Tsuchiya et al.

Integrated Information Theory doesn’t Address the Hard Problem

Just in case you are not aware Hakwan Lau has started a blog, In Consciousness we Trust, where he is blogging his work on his upcoming book on consciousness. He has lately been taking fire at the Integrated Information Theory of Consciousness and has a nice (I think updated) version of his talk (mentioned previously here) in his post How to make IIT (and other Theories of Consciousness) Respectable. I have some small quibbles with some of what he says but overall we agree on a lot (surprised? 😉 At any rate I was led to this paper by Sasai, Boly, Menson, and Tononi arguing that they have achieved a “functional split brain” in an intact subject. This is very interesting, and I enjoyed the paper a lot but right at the beginning it has this troublesome set of sentences:

A remarkable finding in neuroscience is that after the two cerebral hemispheres are disconnected to reduce epileptic seizures through the surgical sectioning of around 200 million connections, patients continue to behave in a largely normal manner (1). Just as remarkably, subsequent experiments have shown that after the split-brain operation, two separate streams of consciousness coexist within a single brain, one per hemisphere (2, 3). For example, in many such studies, each hemisphere can successfully perform various cognitive tasks, including binary decisions (4) or visual attentional search (5), independent of the other, as well as report on what it experiences. Intriguingly, anatomical split brains can even perform better than controls in some dual-task conditions (6, 7).

Really?!?! Experiments have shown this? I was surprised to read such a bold statement of a rather questionable assumption. In the first place I think it is important to note that these patients do not verbally report on what it ‘experiences’. I have argued that these kinds of (anatomical) spit brains may have just one stream of consciousness (associated with the one capable of verbally reporting) and that the other ‘mute’ hemisphere is processing information non-consciousnesly.

This is one of the problems that I personally have with the approach that IIT takes. They start with ‘axioms’ which are really (question begging) assumptions about the way that consciousness is, and they tout his as a major advance in consciousness research because it takes the Hard Problem seriously. But does it? As they put it,

The reason why some neural mechanisms, but not others, should be associated with consciousness has been called ‘the hard problem’ because it seems to defy the possibility of a scientific explanation. In this Opinion article, we provide an overview of the integrated information theory (IIT) of consciousness, which has been developed over the past few years. IIT addresses the hard problem in a new way. It does not start from the brain and ask how it could give rise to experience; instead, it starts from the essential phenomenal properties of experience, or axioms, and infers postulates about the characteristics that are required of its physical substrate.

But this inversion doesn’t serve to address the Hard Problem, (by the way, I agree with the way the formulate it for the most part). I agree that the Hard Problem is one of trying to explain why a given neural activation is associated with a certain conscious experience rather than another one, or none at all. And I even agree that in order to address this problem we need a theory of what consciousness is but IIT isn’t that kind of theory.  And this is because of the ‘fundamental identity claim’ of IIT that an experience is identical to a conceptual structure, where ‘experience’ means phenomenally conscious experience and ‘conceptual structure’ is a technical term of Integrated Information Theory.

This is a postulated identity, and they do want to try to test it, but even if it was successfully confirmed would it really offer us an explanation of why the experiences are associated with a particular brain activity? To see that the answer is no consider their own example from Figure 1 of their paper and what they say about it. nrn.2016.44_IIT - From Consciousness to Physical Substrate

They begin,

The true physical substrate of the depicted experience (seeing one’s hands on the piano) and the associated conceptual structure are highly complex. To allow a complete analysis of conceptual structures, the physical substrate illustrated here was chosen to be extremely simple1,2: four logic gates (labelled A, B, C and D, where A is a Majority (MAJ) gate, B is an OR gate, and C and D are AND gates; the straight arrows indicate connections among the logic gates, the curved arrows indicate self-connections) are shown in a particular state (ON or OFF).

So far so good. We have a simplified cause-effect structure in order to make the claim clear.

The analysis of this system, performed according to the postulates of IIT, identifies a conceptual structure supported by a complex constituted of the elements A, B and C in their current ON states. The borders of the complex, which include elements A, B, and C but exclude element D, are indicated by the green circle. According to IIT, such a complex would be a physical substrate of consciousness

So, when A=B=C=1 (i.e. on) in this system it is having a conscious experience (!), as they say,

The fundamental identity postulated by IIT claims that the set of concepts and their relations that compose the conceptual structure are identical to the quality of the experience. This is how the experience feels — what it is like to be the complex ABC in its current state 111. The intrinsic irreducibility of the entire conceptual structure (Φmax, a non-negative number) reflects how much consciousness there is (the quantity of the experience). The irreducibility of each concept (φmax) reflects how much each phenomenal distinction exists within the experience. Different experiences correspond to different conceptual structures.

Ok then. Here we have a simple system that is having a conscious experience, ex hypothesi, and we know everything about this system. We know that it has these  concepts specified by IIT, but what is it’s conscious experience like? What it is like to be this simple system of 4 logic gates when its elements A, B, and C are on? We aren’t told and there doesn’t seem to be any way to figure it out based on IIT. It seems to me that there should be no conscious experience associated with this activity, so it is easy to ‘conceive of a physical duplicate of this system with no conscious experience’…is this a zombie system? That is tongue in cheek but I guess that IIT proponents will need to say that since the identity is necessary I can’t really conceive of it (or that I can but it is not really possible). Can’t we conceive of two of these systems with inverted conscious experiences (same conceptual structures)? Why or why not? I can’t see anything in IIT that would help to answer these questions.

If IIT is attempting to provide a solution to the Hard Problem of Consciousness then should allow us to know what the conscious experience of this system is like, but it seems like it could be having any, or none (how difficult would it then be to extend this to Nagel’s bat!?!?). There are some who might object that this is asking too much. Isn’t this more like Ned Block’s “Harder Problem” than Chalmers’ Hard Problem? Here I suppose that I disagree with the overly narrow way of putting the Hard Problem. It isn’t merely about how this brain state is associated with a particular phenomenal quality rather than none at all, it is how it is associated with any physical, functional state at all that os the Hard Problem. Sure brain states are one kind of physical state and so the problem arises there but more generally the Hard Problem is answering the question of why any physical state is associated with any qualitative state at all instead of another or none at all.

IIT, and Tononi in particular, seem committed to giving us an answer. For instance, in his Scholarpedia article on IIT Tononi says,

IIT employs the postulates to derive, for any particular system of elements in a state, whether it has consciousness, how much, and of which kind.

But how do we do this for the 4 logic gates?

How do we do it in our own case?

 

Integrated Information Theory is not a Theory of Consciousness

The Integrated Information Theory of Consciousness has been garnering some attention lately. There was even a very high profile piece in Nature. Having just listened to Hakwan Lau’s talk on this (available at this conference website) I thought I would write down a couple of reactions.

Like everyone else who is interested in consciousness, I have been interested in the integrated Information Theory. I attended a talk by Tononi back in 2012 (and wrote about it here) but I also attended a workshop at NYU on it back in 2015. I had always meant to write something about it (John Horgan did here) and thought I would do so now. I wish I had written about this sooner, but to be completely honest I found out about the Paris attacks as I was leaving the workshop and it shook me up enough to distract me from blogging.

I had a couple of take-away’s from that workshop and these have really influenced how I have thought about IIT. I suppose I would sum it up by saying that IIT doesn’t look like a theory of consciousness. In the first place it purports to be a theory of phenomenal consciousness, what it is like for one to have a conscious experience, but it starts from the phenomenon of fading into a dreamless sleep. This makes it look like the main phenomenon is creature consciousness. Is IIT trying to give an account of the transition(s) from sleeping to wakefulness (and vice versa)? This is where ‘levels of consciousness’ talk seems most at home. Is being in hypnogogic reverie ‘in between’ sleeping and wakefulness? Probably yes, but does that translate to phenomenal consciousness being graded? There it seems less clear. You either have phenomenal consciousness or you do not (pace Dennett). It is the contents of consciousness that can be graded, distorted, etc. So right from the beginning it seems to me to be off on the wrong foot: the comparison is not that between waking and dreamless sleep, it is the comparison between conscious (i.e. reported) and unconscious (denied) states that one should begin with if one is looking to explain consciousness.

Another of the main ideas that came out of the workshop (again, for me) was that the ‘axioms’ of IIT seem to encode assumptions about conscious experience that are controversial. For example, is some kind of higher-order awareness necessary (and/or sufficient) for conscious experience? The axioms are silent on this, seeming to suggest that the answer is no, but a lot of people seem to think that there is a kind of higher-order awareness that is manifest in our phenomenology (old examples like Aristotle, and newer ones like Brentono, and even newer ones like Uriah Kriegel). So could we have another version of IIT that adds an axiom about consciousness requiring higher-order awareness? Can this axiom be mathematized? Or could we interpret the first axiom (i.e. consciousness exists from *my* perspective) as implying higher-order awareness?

The current defenders of IIT clearly have a first-order theory of consciousness in mind when they discuss Sperling. They say in their Nature Neuroscience Reviews paper,

In short, the information that specifies an experience is much larger
than the purported limited capacity of consciousness

But there is no argument for this other than that IIT predicts it! Doesn’t it seem the least bit fishy that a theory that starts off with axioms that encode first-order assumptions about consciousness ends up ‘predicting’ first-order readings of controversial experiments? There is nothing in IIT that seems to indicate that we should not instead say that the Sperling distinctions encoded in the integrated information are unconscious and what is conscious is just what the subjects report.

Thus it seems to me that IIT is best interpreted as giving an account of mental content. This mental content may be conscious but it may also be unconscious. To resolve this debate we need to go back to the usual debate between first-order and higher-order theories of consciousness. IIT seems to have added nothing to this debate and we would need to resolve it in the usual way (by argument, appeal to phenomenology, and experimental evidence).

Finally another of the main ideas to come out of the workshop, for me, was that IIT, can be interpreted differently from the metaphysical point of view as well. Is IIT physicalist or dualist? Well, it seems you could have a version of it that went ether way. You could, like David Chalmers seems to incline towards, view IIT as giving you a handle on what the physical correlates of consciousness might be, and then one would posit, in addition, a fundamental law of nature connecting states of physically integrated information with conscious states. This is clearly not the way that Tononi wants the theory to be developed but it is a consistent way to develop the theory. On the other hand one might end up with a physicalist version of IIT, identifying consciousness with the physical implementation of the integrated information. Or you could, like Tononi, claim that consciousness is identical to the ‘conceptual structure’ which exists over and above the parts which make it up (conceptual structures are irreducible to their physical parts for Tononi). So which one of these is the real IIT? Well, there is Tononi’s IIT and then there might be Chalmers’ IIT, etc.

This is not even to mention the problems others have pointed out, that it is hard to know what to make of a grid being ‘more conscious’ than a typical Human, or which of the many (many) different ways of formulating phi are correct, or whether it is even possible to measure phi in humans at all. Even if one wasn’t worried by any of that it still seems that IIT leaves open all of the most important questions about the ultimate nature of consciousness.

 

Eliminative Non-Materialism

It struck me today that all of the eliminativists about the mind are physicalists (or materialists) and a quick google search didn’t reveal any eliminativist dualist out there. But why is that?

I can see why a particular kind of dualist would reject eliminativism. If one held that the mind was transparent to itself in a strong way then the existence of beliefs and other mental states can be known directly via the first-person method of introspection. But does that exhaust the possibilities? Suppose one thought that there was a robust correlation (or even causation) between the brain and mind. Then one would expect a robust NCC for every conscious state (assuming a law-like connection or at least correlation between the brain and mental states).

To give us a model to work with let’s assume that there is correlation between function states of the brain and consciousness such that whenever certain functional states are realized that guarantees (given our laws of physics, etc) that a certain (non-physical) state of consciousness is also instantiated. Now suppose that we have a pretty good functional definition for what the functional correlate of a given metal state should be. That is, suppose we have worked out in a fair amount of detail what kinds of functional states we expect would be correlated with the conscious mental states posited by folk-psychology. Now further suppose that when we advanced far enough into our neuroscience we saw that there were no such states realized in the brain or that the states were somewhat what we thought but varied in some dramatic way from what we had worked out folk-psychologically.

At that point it seems we would have two options. One thing we could do is to maintain that there is after all no law-like correlation between brain states and mental states. There is a belief or a red quale, say, but it is somehow instantiated in a way independently from the neural workings. This seems like a bad option. The second option would be to abandon folk-psychology and say that the non-physical states of mind are better captured by what the correlates are suggesting. The newly non-physical states might be so different from the original folk-psychological postulates that we might be tempted to say that the originally postulated states don’t exist. Wouldn’t we then have arrived at an eliminative non-materialism?

As a corollary, doesn’t this possibility suggest that there aren’t any truly a priori truths knowable from introspection?