Levin on Brown

My paper Deprioritizing the A Priori Arguments Against Physicalism, which was a product of the online consciousness conference, directly grew out of blog discussions I had around here shortly after I started this blog in May of 2007 (which, by the way, I just noticed, means that the 10 year anniversary of Philosophy Sucks! is coming up soon!!)…at that time I had been interested in modal arguments against physicalism but had no plans at all of writing a paper on zombies. At any rate this paper has become my second most cited paper (and is even cited by the Stanford Encyclopedia of Philosophy’s entry on Zombies (and the Wikipedia one too!)) but it is usually cited en passant, so to speak, so it is nice to see some actual discussion of the argument.

Janet Levin discusses it in her paper Do Conceivability Arguments Beg the Question Against Physicalism? which was published in the 2014 issue of Philosophical Topics that I edited as a result of the 4th online consciousness conference. At the time I was putting the issue together I contemplated writing something about it in a brief response but decided to wait. ‘Better late than never’ is quickly becoming my motto!

Levin starts with Perry’s response to the zombie argument in his 2001 book Knowledge, Possibility, and Consciousness and I think this is a good place to start. As a bit of an aside Perry’s book  has been hugely influential on me. I read it in my philosophy of mind course, with Kent Bach, in the fall of 2001 and at the time I remember feeling that the identity theory was not really given the due that it deserved and then I saw Perry defending it and it gave me hope. I even invited him out to SFSU to give a talk to the philosophy club as a result and he did. This may have been my first attempt at organizing an academic event! The paper I wrote for that class, “Sticking to the Subject: My Response to Chalmers’ Response to Perry” became my writing sample when I applied to PhD programs. I rewrote it with feedback from the class and afterwards when I approached him with this as a potential writing sample….I think I used to have this up on my website at some point when I was in Connecticut but it seems to be lost now (especially after my pre-cloud computer crash back in 2004 or 2005). I  only have a vague notion of what was in that paper and it would be interesting to see it again.

(On another tangent I also recall this book influenced a paper I wrote for my epistemology class I had in the spring of 2002 (also with Kent Bach) where I argued that adopting Perry’s view showed us how we can say that when I play Resident Evil and have thoughts like “there’s a green herb in the basement” they come out true (and how this shows a way to avoid skepticism)).

…But back to Levin’s critique. Here is what she says,

In his (2010), Richard Brown argues that the zombie argument (and its relatives) beg the question; they seem compelling only to those who already assume that qualitative properties are not physical.

One thing that I think has become clear over the years is that I was not clear enough in the original paper about my background assumptions and intentions. I had been used to arguing with people like David Chalmers and Richard Chappell and they were both very strong supporters of a priori reasoning and some version of two-dimensional semantics. So when I said that the zombie argument begged the question I meant that it begged the question against a physicalist who accepted the link between conceivability and possibility. I was trying to show that even if you grant all of the other assumptions that dualists make they still do not have an argument against physicalism. I didn’t really intend this to be a claim that the zombie argument begged the question against those who accepted type-B physicalism, or who otherwise denied the link between conceivability and possibility (as I am in some moods likely to do).

So how was this supposed to play out? As Levin says, I attempt to show this by

…presenting conceivability arguments analogous to the Zombie Argument that aim to support, rather than undermine, physicalism.  In particular, Brown argues for the conceivability of Zoombies; that is (p. 50), ‘creatures non-physically identical to me in every respect and which lack any non-physical phenomenal consciousness’, and also of Shombies; that is (p. 51), ‘creature[s] that [are] microphysically identical to me, ha[ve] conscious experience, and [are] completely physical’, and suggests that arguments with such conceivability premises will seem as compelling to physicalists as the zombie argument seems to dualists.

I can see why she says this but I would like to clear this up a bit.

First, I never intended my paper to offer any support for physicalism. I took the point to be that we did not have any good reason to think it was false, or that the a priori arguments against it did not show it to be false (currently, that is. Whatever their potential to do so in the future amounts to they do not presently constitute a reason to think that physicalism is false). Perhaps this is in fact to offer some kind of indirect support for physicalism but even so the conceivability arguments she is here discussing were aimed at showing that dualism is false. So take the pair {zombie, shombie}. If one accepts a two-dimensional semantics and one buys the general arguments against strong necessitates, then only one of this pair is truly ideally conceivable and the other is necessarily inconceivable. That much is common ground between those who accept two-dimensional semantics )and I do for the purposes of this argument…and sometimes for other purposes as well). But which one of this pair is ideally conceivable? No one has really been able to show that either one leads to a contradiction.

So, as I stressed above, given this set of background assumptions then I think the zombie argument is question begging. It begs the question by assuming that it is zombies that are truly ideally conceivable and not shombies. But if I am working inside 2D semantics then I find shombies to be conceivable and so that means zombies have to be the ones that are ideally inconceivable, even if I cannot yet say why. It is at this point, from within the 2D framework that the standoff manifests most strongly. As the Stanford encyclopedia entry on zombies suggests the best option for the dualist like Dave is to maintain that shombies are inconceivable (Dave has said this as well) but when pressed on why they are all that can be said is that many people have found it very hard to see how physicalism could be true of consciousness. But that is just to say that shombies are incredible for him, just as zombies are for me.

And this is just what Levin herself says, as we’ll see below. She goes one to say,

More precisely, Brown argues that Zoombies and Shombies—along with zombies—are all prima facie conceivable, and contends (like the theorists discussed above) that one’s antecedent theoretical commitments determine one’s convictions about which of these creatures will be ideally conceivable, conceivable ‘in the limit’.  And, though he is officially neutral about what the ultimate outcome will be, he suggests that if we were to learn, and sufficiently attend to, all the (not yet discovered) physical and functional facts about the world, we would be able to recognize that these facts do indeed entail that certain of our internal states are conscious experiences.

I would balk at this way of putting things. It is true that I am neutral about which one is ultimately truly conceivable but I do not think that it must be the case that we end up being able to make these deductions. I only think this is a possibility and that it is not ruled out by the conceivability arguments against physicalism. I do think that for different people different combinations of zombies and shombies will seem to be conceivable/inconceivable and that it is one’s background theoretical commitments that tacitly determine which is which.

I will also say that one thing that has been somewhat disappointing is that the suggestion that we may be able to make deductions a priori from physical states to phenomenal states only when we have the relevant concepts, whatever those turn out to be. So, Mary cannot do it in her room unless she has the relevant phenomenal concept (I can be neutral on what exactly these are and do not mean to endorse any account of them here). I have always thought that this was the best way to respond to the Mary case and I do not see it being discussed very much. I wish it were!

The main problem Levin has with what I say is something she points out as a flaw in Perry’s argument as well. She says,

Brown characterizes his view as a species of (what Chalmers calls) Type-C physicalism, the view that, although zombies may be conceivable now, they would be inconceivable ‘in the limit’.   But of course dualists would deny this, and it’s worth getting clear about what, on Brown’s view, could account for the eventual inconceivability of zombies.  First (p. 49) he likens the (prima facie) conceivability of zombies for us now to the prima facie conceivability of H2O in the absence of water for those living in the early 18th century, and suggests that, just as further empirical discoveries made H2O without water inconceivable, so further empirical discoveries will do the same for zombies. But this argument, like the ones discussed above, relies on a questionable analogy.  At least arguably—as noted before—what enables us (and not our 18th century counterparts) to deduce water facts from H2O facts is not merely that we have increased our empirical information, although this, to be sure, is crucial.  In addition, we, at least implicitly, appeal to certain principles that go beyond one’s empirical or methodological ‘theoretical commitments’; in particular, that the referent of ‘water’ is a  (natural) kind of stuff (e.g. the stuff that fills our lakes and comes out of our faucets or, alternatively—pointing to a lake or a puddle—that kind of stuff), and that natural kinds are to be individuated by their compositional properties (such as being composed of H2O).  But it is not clear that there are analogous principles which, when combined with our knowledge of the structure and function of the brain and central nervous system, would permit the deduction of facts about conscious experience from even a complete statement of the physical and functional facts.  And thus, it seems, it is plausible to think that even those committed to physicalism and open to further information about the structure and function of the brain will continue to find zombies conceivable.

I think I partially agree with what she is saying here. Especially with respect to the ‘extra empirical’ factors relevant to theory adoption in general.

Levin’s comments can be made especially poignant for the ‘water is H2O’ example. To anyone really interested in these issues I would recommend  reading Hasok Cheng’s book Is Water H2O? Evidence, Realism, and Pluralism, which was recommended to me after a talk I gave in Taiwan at the Academia Senica. This book really clarified a lot of the technical philosophical and empirical issues about the theoretical identity of water and H2O and I think it does highlight similar kinds of extra empirical forces at work in the history of science. I highly recommend it to anyone interested in these issues. But I am not sure why this kind of point is supposed to count against  the claim I am making. It seems to me to further support it!

If I am reading Levin right it looks like she is arguing that we may be Type B physicalists at the limit. That is, we may learn all of the physical facts and yet still find that zombies are conceivable even if we become otherwise convinced that physicalism is true. I agree that this is a possibility and this is why I think it is correct to say none of these arguments (employing zombies or shombies) are question begging tout court. They beg the question against a particular way of thinking about physicalism.

I also tend to agree that in the background of my thinking is something like what she points to about natural kinds. Especially in this case where I am interested in being as close to two-dimensional semantics as possible (because part of me thinks it is nice view to have). If one takes that point of view then consciousness is similar enough in that it can be picked out by a primary intension. We can, I think, attend to specific instances of phenomenal consciousness and say ‘that kind of stuff’ and thereby pick something out. So while I agree that my way of thinking is not the only way or forced up on in any way I am more concerned with arguing that this way of thinking is not (currently) threatened by any a priori arguments.

This is because my aim is not to establish physicalism but to show that arguments aimed at undermining it don’t do so without further assumptions. Even if you grant that the ideal conceivability of zombies would show that physicalism is false we need more than that. We need to also know that zombies are in fact ideally conceivable, and that is why homies are problematic. They must be inconceivable but then why can I, and so many others, conceive of them? The reason is, I suggested, that neither side has been able to show what contradiction is (or could be) entailed by the other side. Dualists and type B physicalists correctly point out that no one has made a successful case for why zombies are  inconceivable but, less often pointed out of late, it is also the case that no one has shown what contradiction is entailed by shombies. As far as we can tell at this point either both are ideally conceivable and so 2-dimensional semantics and modal rational fail or only one of the pair is ideally conceivable and we don’t presently know which one it is.

I think that Levin herself arrives at something like this position as well, as we’ll see. She goes on to say,

In a related argument, Brown suggests (p 55) that what could permit ‘the deduction of the phenomenal facts from the physical facts is the (for us) a posteriori discovery of identities between phenomenal and physical properties’.  But given the asymmetry discussed above, one may wonder, on behalf of dualists, what makes it plausible to think that any such a posteriori discovery could occur.  The answer, Brown maintains (pp. 55-56), is that further empirical investigation is likely to show that (contrary to Chalmers, et al and also Type B physicalists) ‘we will have discovered that phenomenal properties can be explained in broadly functional terms’, and goes on to argue that ‘this does not thereby endorse Type A physicalism.  It is just to point out that I cannot really conceive of anything else doing any explanatory work…No one has ever given anything like a proper account of what non-physical properties are or how they explain phenomenal consciousness.’

This, however—as for Perry—seems to be a matter not of zombies’ being inconceivable, but rather incredible, and the plausibility of Type C physicalism depends on the plausibility of the former, stronger, claim.  In short, there is no particular reason to think that any further discoveries of the neural structure of the brain and psychological laws governing mind-body interactions will provide information of a different sort from the information we have now.  And given that there seem to be no a priori links between physical (or physical-functional) and phenomenal concepts, and no a priori principles determining the nature or essential properties of the items denoted by our phenomenal concepts (other than that they must feel a certain way), it’s hard to see how zombies could become inconceivable—even in the limit.

Here I completely agree with her and in fact I think this is part of the point that I was trying to make.  Some people seem to find zombies conceivable, some people seem to find shombies conceivable. Since I am assuming that our reasoning capabilities are good enough for this (another common assumption between Chalmers and I for this argument) that leaves only empirical or conceptual issues left. So I agree that we haven’t yet got the story. I have argued that something like the higher-order theory will help but really the larger point is that we need a theory of consciousness and empirical data to move forward.

Again I would also point out that I think that part of the story here must invoke something about how these identities could be established. Here I think we could have a 2D version but also a version like that of Ned Block (that is a non-two-dimensional account). I am attracted to both kinds of pictures about the way these identities will be discovered.

But all of that to one side the whole point is that we cannot start from the assumption that zombies are in fact ideally conceivable. They may *seem* to be so *to you* given what *we know now* but this is not at all the same thing as their actually really being ideally conceivable, as shombies show. If one or the other were truly ideally conceivable *at this point in time* then we wold be able to show what contradiction is entailed by the zombie or shombie world. Thus, until that can be done, instead of ‘physicalism is false’ the best we get from the zombie argument is ‘it seems to me now that physicalism is false’. I hope it goes with out saying that I think the same is the case for the a priori arguments from the physicalist.

On a final note, Levin says in a footnote that Thomas Nagel in his 1965 paper Physicalism discusses cases like zoombies. Zoombies were supposed to be non-physical duplicates of me which lack consciousness. These creatures have all of my non-physical properties and yet they do not have consciousness. This seems conceivable to me, but is this what Nagel is talking about? When I went and re-read that paper it seemed like a warm up for his Bat paper and at the end he is talking about indexical information (which seems to be part of the story about how I became part of PQTI in Chalmers’ work and may be a precursor to Perry’s work). Maybe this is what she meant? I might have to re-re-read it…anyone else see the similarity?

Chalmers on Brown on Chalmers

I just found out that the double special issue of the Journal of Consciousness Studies devoted to David Chalmers’ paper The Singularity: A Philosophical Analysis recently came out as a book! I had a short paper in that collection that stemmed from some thoughts I had about zombies and simulated worlds (I posted about them here and here). Dave responded to all of the articles (here) and I just realized that I never wrote anything about that response!

I have always had a love/hate relationship with this paper. On the one hand I felt like there was an idea worth developing, one that started to take shape back in 2009. On the other hand there was a pretty tight deadline for the special issue and I did not feel like I had really got ahold of what the main idea was supposed to be, in my own thinking. I felt rushed and secretly wished I could wait a year or two to think about it. But this was before I had tenure and I thought it would be a bad move to miss this opportunity. The end result is that I think the paper is flawed but I still feel like there is an interesting idea lurking about that needs to be more fully developed. Besides, I thought, the response from Dave would give me an opportunity to think more deeply about these issues and would be something I could respond to…that was five years ago! Well, I guess better late than never so here goes.

My paper was divided into two parts. As Dave says,

First, [Brown] cites my 1990 discussion piece “How Cartesian dualism might have been true”, in which I argued that creatures who live in simulated environments with separated simulated cognitive processes would endorse Cartesian dualism. The cognitive processes that drive their behavior would be entirely distinct from the processes that govern their environment, and an investigation of the latter would reveal no sign of the former: they will not find brains inside their heads driving their behavior, for example. Brown notes that the same could apply even if the creatures are zombies, so this sort of dualism does not essentially involve consciousness. I think this is right: we might call it process dualism, because it is a dualism of two distinct sorts of processes. If the cognitive processes essentially involve consciousness, then we have something akin to traditional Cartesian dualism; if not, then we have a different sort of interactive dualism.

Looking back on this now I think that I can say that part of the idea I had was that what Dave here calls ‘process dualism’ is really what lies behind the conceivability of zombies. Instead of testing whether (one thinks that) dualism or physicalism is true about consciousness the two-dimensional argument against materialism is really testing whether one thinks that consciousness is  grounded in biological or functional/computational properties. This debate is distinct and orthogonal to the debate about physicalism/dualism.

In the next part of the response Dave addresses my attempted extension of this point to try to reconcile the conceivability of zombies with what I called ‘biologism’. Biologism was supposed to be a word to distinguish the debate between the physicalist and the dualist from the debate between the biologically-oriented views of the mind as against the computationally oriented views. At the time I thought this term was coined by me and it was supposed to be an umbrella term that would have biological materialism as a particular variant. I should note before going on that it was only after the paper was published that I became aware that this term has a history and is associated with certain views about ‘the use of biological explanations in the analysis of social situations‘. This is not what I intended and had I known that beforehand I would have tried to coin a different term.

The point was to try to emphasize that this debate was supposed to be distinct from the debate about physicalism and that one could endorse this kind of view even if one rejected biological materialism. The family of views I was interested in defending can be summed up as holding that consciousness is ultimately grounded in or caused by some biological property of the brain and that a simulation of the brain would lack that property. This is compatible with materialism (=identity theory) but also dualism. One could be a dualist and yet hold that only biological agents could have the required relation to the non-physical mind. Indeed I would say that in my experience this is the view of the vast majority of those who accept dualism (by which I mostly mean my students). Having said that it is true that in my own thinking I lean towards physicalism (though as a side-side note I do not think that physicalism is true, only that we have no good reason to reject it) and it is certainly true that in the paper I say that this can be used to make the relevant claim about biological materialism.

At any rate, here is what Dave says about my argument.

Brown goes on to argue that simulated worlds show how one can reconcile biological materialism with the conceivability and possibility of zombies. If biological materialism is true, a perfect simulation of a biological conscious being will not be conscious. But if it is a perfect simulation in a world that perfectly simulates our physics, it will be a physical duplicate of the original. So it will be a physical duplicate without consciousness: a zombie.

I think Brown’s argument goes wrong at the second step. A perfect simulation of a physical system is not a physical duplicate of that system. A perfect simulation of a brain on a computer is not made of neurons, for example; it is made of silicon. So the zombie in question is a merely functional duplicate of a conscious being, not a physical duplicate. And of course biological materialism is quite consistent with functional duplicates.

It is true that from the point of view of beings in the simulation, the simulated being will seem to have the same physical structure that the original being seems to us to have in our world. But this does not entail that it is a physical duplicate, any more than the watery stuff on Twin Earth that looks like water really is water. (See note 7 in “The Matrix as metaphysics” for more here.) To put matters technically (nonphilosophers can skip!), if P is a physical specification of the original being in our world, the simulated being may satisfy the primary intension of P (relative to an inhabitant of the simulated world), but it will not satisfy the secondary intension of P. For zombies to be possible in the sense relevant to materialism, a being satisfying the secondary intension of P is required. At best, we can say that zombies are (primarily) conceivable and (primarily) possible— but this possibility mere reflects the (secondary) possibility of a microfunctional duplicate of a conscious being without consciousness, and not a full physical duplicate. In effect, on a biological view the intrinsic basis of the microphysical functions will make a difference to consciousness. To that extent the view might be seen as a variant of what is sometimes known as Russellian monism, on which the intrinsic nature of physical processes is what is key to consciousness (though unlike other versions of Russellian monism, this version need not be committed to an a priori entailment from the underlying processes to consciousness).

I have to say that I am sympathetic with Dave in the way he diagnoses the flaw in the argument in the paper. It is a mistake to think of the simulated world, with its simulated creatures, as being a physical duplicate of our world in the right way; especially if this simulation is taking place in the original non-simulated world. If the biological view is correct then it is just a functional duplicate, true a microfunctional duplicate, but not a physical duplicate.

While I think this is right I also think the issues are complicated. For example take the typical Russellian pan(proto)psychism that is currently being explored by Chalmers and others. This view is touted as being compatible with the conceivability of zombies because we can conceive of a duplicate of our physics as long as we mean the structural, non-intrinsic properties. Since physics, on this view, describes only these structural features we can count the zombie world as having our physics in the narrow sense. The issues here are complex but this looks superficially just like the situation described in my paper. The simulated world captures all of the structural features of physics but leaves out whatever biological properties are necessary and in this sense the reasoning of the paper holds up.

This is why I think the comparison with Russellian monism invoked by Dave is helpful. In fact when I pitched my commentary to Dave I included this comparison with Russellian monism but it did not get developed in the paper. At any rate, I think what it helps us to see is the many ways in which we can *almost* conceive of zombies. This is a point that I have made going back to some of my earliest writings about zombies.  If the identity theory is true, or if some kind of biological view about consciousness is true, then there is some (as yet to be discovered) property/properties of biological neural states which necessitate/cause /just are the existence of phenomenal consciousness. Since we don’t know what this property is (yet) and since we don’t yet understand how it could necessitate/cause/etc phenomenal consciousness, we may fail to include it in our conceptualization of a ‘zombie world’. Or we may include it and fail to recognize that this entails a contradiction. I am sympathetic to both of these claims.

On the one hand, we can certainly conceive of a world very nearly physically just like ours. This world may have all/most of the same physical properties, excepting certain necessary biological properties, and as a result the creatures will behave in indistinguishable ways from us (given certain other assumptions). On the other hand we may conceive of the zombie twin as a biologically exact duplicate in which case we do not see that this is not actually a conceivable situation. If we knew the full biological story we would be, or at least could be, in a position to see that we had misdescribed the situation in just the same way as someone who did not know enough chemistry might think they could conceive of h2o failing to be water (in a world otherwise physically just like ours). This is what I take to be the essence of the Krpkean strategy. We allow that the thing in question is a metaphysical possibility but then argue that it is actually misdescribed in the original argument. While misdescribing it we think (mistakenly) we have conceived of a certain situation being true but really we have conceived of a slightly different situation being true and this one is compatible with physicalism.

Thus while I think the issues are complex and that I did not get them right in the paper I still think the paper is morally correct. To the extent that biological materialism resembles Russellian monism is the extent to which the zombie argument is irrelevant.

Professor Shombie

I had planned on posting here more once back from Taiwan but that has’t exactly worked out! If one wants to see the videos from the conference in Taiwan they are here and I will eventually write up a paper from my talk (and the one I gave at the Grad Center). Even so lots has been going on. I am also happy to announce that I am now officially Tenured and promoted to Full Professor! Tenured Full Professor…It hasn’t quite sunk in yet but it is still pretty cool.

In other news I am getting ready to head up to UConn to give a talk. I left UConn way back in 2003 to come to NYC and I went back in 2007 to participate in the Yale/UCONN graduate conference but I haven’t been back since then so I am looking forward to it! I figure since it is so close to Halloween I will talk about ways to kill zombies. In particular I have been thinking a lot about the 2D argument against dualism and plan to present an updated version of that. I have a draft up at PhilPaper which I wrote after my presentation at the Towards a Science of Consciousness conference back in 2012 and the helpful comments from Dave on the linked to post but I think I have a better way to present it now.

The main points are the same: The shombie argument is aimed at establishing the falsity of dualism, not the truth of physicalism. Physicalism can be formulated as the familiar [](P ⊃ Q) and dualism can be formulated as the claim that it is necessary that if all there is in a world is the physics of our world then there is no consciousness at that world. We can symbolize that as [](PT ⊃ ~Q). Here PT is the conjunction of the familiar P (a complete description of the fundamental microphysics of our world, laws and particles, etc) together with a ‘that’s all’ clause. To show that this is false we need to show that it is possible that we could have PT and at the same time Q. In symbols ◊(PT & Q). So the shombie argument is as follows. PT & Q is conceivable and so possible. From that it follows that [](PT ⊃ ~Q) is false. From here the main action is how to understand the that’s all clause. Dave suggested a modal and non-modal (see the paper or his comments) way to interpret it and I think either of those would work. There are tricky issues about parity here and whatever turns out to be the case for shombies should be the case for the zombie argument as well. So if we need to invoke modal notions, or notions of fundamentality to describe the shombie world then I am happy with that as long as we also need to do it to describe zombie worlds.

However that turns out I think we can describe the shombie world without any modal terms in any of the premises. I understand the shombie world to roughly be the following kind of world. For everything that exists in that world there is a physical property which is that thing. We can symbolize this as: (x)[∃y(y=x) ⊃ ∃z(Pz & (z=x))]. This says that for anything that exists there is some physical property which is that thing. Here one might object that the identity statement in the consequent already has modal notions smuggled in but I think we can get rid of this as well. The basic idea is that we have a non-modal way of understanding what it means to say that x is identical to y, it just means that if x has some property F then so does y. In symbols this is (x=y) ⊃ (Fx ⊃ Fy). We can substitute this into the above to get (x)[∃y(y=x) ⊃ ∃z(Pz & (Fz ⊃ Fx))] which is now a non-modal ‘that’s all’ clause. It says that for any object which exists there is some physical property (which may be very complex) such that if that property is a certain way then so is the physical object. It may be the case that I need something like ‘for all F, if z is F then x is F’ or maybe even ‘for all F, z is F if and only if Fx’ but either way there are no modal claims here. We simply imagine one world where consciousness is physical and that is enough to show that dualism is false. We do not need to imagine anything complicated like that it is possible that it is necessary that P entails Q.

In the course of re-working all of this it struck me that I spend a lot of time trying to show that the zombie argument (and related scenarios like inversions etc) are not relevant to the question of physicalism. Thus I think that in the shombie case if one is partial to modal rationalism (as I sometimes am) then only one of the pair (zombies, shombies) can be ideally conceivable and different people find them differently conceivable. Thus for us these intuitions are not helpful one way or the other. This was also the point I was trying to make in my short paper Zombies and Simulation which was in the JCS issue on Dave’s singularity paper. But another route to this kind of conclusion just struck me.

Suppose that the identity theory is true, so that consciousness in our world is (necessarily) physical, let us symbolize that as b=q, where b is some brain state and q is some episode of consciousness. If the identity theory is true are zombies conceivable (and you accept modal rationalism)? The answer seems to be ‘no’. For, suppose that b=q as we have said. Then someone who said that you could have a physical duplicate of me, which includes b, and yet lack consciousness, q, would be asserting both that b was and was not instantiated at the possible world in question. It is instantiated because I am described as being in brain state b and yet it is described as not being there because we are told that there is no q, even though we are assuming that b=q. This is like being told that there is H2O (and our laws of physics) and yet no water. If water is H2O then this is not conceivable.

So far so good, but what is often unnoticed is that we can conceive of a creature that is physically just like me except that it is not in brain state b (and so not having conscious experience q). It seems like there is nothing contradictory about the scenario where this creature behaves just like I do when I have the relevant brain state (and thus the relevant conscious experience). This will be a world where there are causal gaps, where, that is, the behavior of our world is duplicated but without the usual causes. So this creature may put its hand in the fire and in me this would cause brain state b (and thus conscious experience q) and this in turn would case me to yell etc. But the creature we are imagining puts its hand in the fire and does not go into the relevant brain state, but does go into the relevant states that cause behavior (and has the relevant beliefs, etc). This creature still has a brain and is very similar to me excepting for the fact that it has no conscious experience (due to lacking those specific brain states) and all of these strange causal gaps (to make its behavior indistinguishable from mine). This creature counts as a zombie, though not the kind that is relevant to physicalism. Thus one kind of zombie threatens the identity theory while the other does not. So which one is really conceivable? I find that I can only really make sense of the non-threatening kind (surprise! surprise!)But what kind of evidence could push us one way or the other? Once again I find conceivability (for now) to be of now use in answering questions about consciousness.

Ok enough for now! I am hoping to make it out to what should be a very interesting discussion of a paper by Jonathan Simon on how to conceive of pain inversions (I hope someday to write up some of the stuff that comes out of the nyu consciousness discussion group but we’ll have to see if Ryland lets me! 🙂

Consciousness and its Place in Physical Reality

In the Spring 2013 semester I initiated a new course at LaGuardia that had the theme Cosmology, Consciousness, and Computation. The basic idea was to explore issues relating to physicalism. Intuitively, physicalism is the view that everything that exists is physical but what is the nature of physical reality? The idea I had was to have the couse divided into three sections. In the first section we would do a conceptual physics course talking about the development of physics from the ancient world to the present day. Then we would turn to issues about consciousness and mind and where they fit in the physical picture we have so far developed. After that we turn to issues about computation; Is the universe computable? Or perhaps does it instantiate some computation? Is consciousness computational? Are we living in a simulation? Is the universe a hologram?

In my quest to have low cost book options for students I have adopted the Terminator book I co-edited and have supplemented that with readings from the Stanford Encyclopedia of Philosophy and other online material. The reception to the course was very good and I am really looking forward to doing it a second time in Fall 2013. I have updated the syllabus and, as usual, would welcome any suggestions or feedback.

Week I: Introduction
• →Richard Brown on What is Philosophy? – http://www.youtube.com/watch?v=ySS0bNeWZOg

Week 2: Early Attempts to Understand Mind and Physical Reality
• →Terminator Ch 10: The Nature of Time and the Universe
• Time- http://plato.stanford.edu/entries/time/
• Richard Brown on Pre-Socratic Philosophy- http://www.youtube.com/watch?v=zfLgRotdcKI&list=PLfR0qhtOKP6eYkUoW7DH8qdjwEyQnsbPJ&index=2
• Pre-Socratic Philosophy- http://plato.stanford.edu/entries/presocratics/
• Ancient Theories of the Soul- http://plato.stanford.edu/entries/ancient-soul/
• Parmenides- http://plato.stanford.edu/entries/parmenides/
• Zeno’s Paradoxes- http://plato.stanford.edu/entries/paradox-zeno/
• Ancient Atomism- http://plato.stanford.edu/entries/atomism-ancient/
• Democritus- http://plato.stanford.edu/entries/democritus/
• Intentionality in Ancient Philosophy- http://plato.stanford.edu/entries/intentionality-ancient/
• Time- http://plato.stanford.edu/entries/time/

Week 3: Modern Philosophy and Modern Science
• →Terminator Ch 2 –Animal consciousness, Descartes, and Emotions
• Descartes’ Physics- http://plato.stanford.edu/entries/descartes-physics/
• Descartes’ Epistemology- http://plato.stanford.edu/entries/descartes-epistemology/
• Descartes’ Theory of Ideas- http://plato.stanford.edu/entries/descartes-ideas/
• Other Minds- http://plato.stanford.edu/entries/other-minds/
• Animal Consciousness- http://plato.stanford.edu/entries/consciousness-animal/
• Locke on Real Essence- http://plato.stanford.edu/entries/real-essence/
• Locke’s Philosophy of Science- http://plato.stanford.edu/entries/locke-philosophy-science/
• Newton’s Philosophy- http://plato.stanford.edu/entries/newton-philosophy/
• Isaac Newton- http://plato.stanford.edu/entries/newton/
• Newton’s Views on Space, Time, and Motion- http://plato.stanford.edu/entries/newton-stm/
• The Contents of Perception- http://plato.stanford.edu/entries/perception-contents/
• The Problem of Perception- http://plato.stanford.edu/entries/perception-problem/

Week 4: Relativity Physics
• →Terminator Ch 8: paradoxes of time travel
• Einstein for Everyone: http://www.pitt.edu/~jdnorton/teaching/HPS_0410/chapters/index.html
• Brian Greene’s The Elegant Universe on NOVA- http://www.pbs.org/wgbh/nova/physics/elegant-universe.html#elegant-universe-einstein.html
• Time Travel and Modern Physics- http://plato.stanford.edu/entries/time-travel-phys/
• Time Machines- http://plato.stanford.edu/entries/time-machine/
• The Equivalence of Mass and Energy- http://plato.stanford.edu/entries/equivME/
• The Hole Argument- http://plato.stanford.edu/entries/spacetime-holearg/
• David Lewis’ The Paradoxes of Time Travel- http://www.csus.edu/indiv/m/merlinos/Paradoxes%20of%20Time%20Travel.pdf

Week 5: Quantum Mechanics
• Brian Greene’s The Fabric of the Cosmos on NOVA- http://www.pbs.org/wgbh/nova/physics/fabric-of-cosmos.html
• Copenhagen Interpretation of Quantum Mechanics: http://plato.stanford.edu/entries/qm-copenhagen/
• Many Worlds Interpretation of Quantum Mechanics- http://plato.stanford.edu/entries/qm-manyworlds/
• The Uncertainty Principle: http://plato.stanford.edu/entries/qt-uncertainty/
• Quantum Entanglement and Information: http://plato.stanford.edu/entries/qt-entangle/
• The Einstein-Podolsky-Rosen Argument in Quantum Theory- http://plato.stanford.edu/entries/qt-epr/
• Measurement in Quantum Theory: http://plato.stanford.edu/entries/qt-measurement/
• Quantum Mechanics- http://plato.stanford.edu/entries/qm/
• Richard Feynman on Double Slit Experiment- http://www.youtube.com/watch?v=hUJfjRoxCbk&list=PLfR0qhtOKP6eYkUoW7DH8qdjwEyQnsbPJ&index=3

Week 6: The Nature and Origin of the Universe
• →The Scale of the Universe- http://htwins.net/scale2/
• Hubble Deep Field: http://hubblesite.org/hubble_discoveries/hubble_deep_field/
• Cosmology and Theology- http://plato.stanford.edu/entries/cosmology-theology/
• Atheism and Agnosticism- http://plato.stanford.edu/entries/atheism-agnosticism/
• Religion and Science- http://plato.stanford.edu/entries/religion-science/
• Teleological Arguments for God’s Existence- http://plato.stanford.edu/entries/teleological-arguments/
• Cosmological Argument- http://plato.stanford.edu/entries/cosmological-argument/
• The Possible Parallel Universe of Dark Matter- http://discovermagazine.com/2013/julyaug/21-the-possible-parallel-universe-of-dark-matter#.UhDhPRbtaz6

Week 7: The Possibility of Life Beyond Earth
• Life- http://plato.stanford.edu/entries/life/
• Molecular Biology- http://plato.stanford.edu/entries/molecular-biology/
• Finding Life Beyond Earth- http://www.youtube.com/watch?v=FVzmGaGCqP8

Week 8: Consciousness in the Physical World?
• Consciousness- http://plato.stanford.edu/entries/consciousness/
• Representational Theories of Consciousness- http://plato.stanford.edu/entries/consciousness-representational/
• Functionalism- http://plato.stanford.edu/entries/functionalism/
• The Mind/Brain Identity Theory- http://plato.stanford.edu/entries/mind-identity/
• Dualism- http://plato.stanford.edu/entries/dualism/
• Zombies- http://plato.stanford.edu/entries/zombies/

Week 9: Beyond Physicalism?
• Eliminative Materialism- http://plato.stanford.edu/entries/materialism-eliminative/
• Folk Psychology as a Theory- http://plato.stanford.edu/entries/folkpsych-theory/
• The Philosophy of Neuroscience- http://plato.stanford.edu/entries/neuroscience/
• Panpsychism- http://plato.stanford.edu/entries/panpsychism/

Week 10: Transhumanism
• →Terminator Ch 4: Extended Mind, Transhumanism
• A History of Transhumanist Thought- http://www.fhi.ox.ac.uk/documents/journal_publications/al/nick_bostrom
• Biohackers: A Journey into Cyborg America- http://www.youtube.com/watch?v=K0WIgU7LRcI&list=PLfR0qhtOKP6eYkUoW7DH8qdjwEyQnsbPJ&index=48
• Tim Cannon on Potential Benefits of Sensory Augmentation- http://www.youtube.com/watch?v=KZ1KCpSL51E&list=PLfR0qhtOKP6eYkUoW7DH8qdjwEyQnsbPJ&index=46
• Aubrey de Grey on Defeating Aging- http://www.youtube.com/watch?v=d1FBJGl2c-Y&list=PLfR0qhtOKP6eYkUoW7DH8qdjwEyQnsbPJ&index=17

Week 11: A.I. and The Singularity
• →Terminator Ch 1: A.I., Chinese Room, Transhumanism
• →Terminator Ch 3: Why always with the killing?
• The Chinese Room Argument- http://plato.stanford.edu/entries/chinese-room/
• The Turing Test- http://plato.stanford.edu/entries/turing-test/
• The Frame Problem- http://plato.stanford.edu/entries/frame-problem/
• David Chalmers’ The Singularity: A Philosophical Analysis- http://consc.net/papers/singularity.pdf
• David Chalmers on Simulation and Singularity- http://www.youtube.com/watch?v=FafHdF_D8gA&list=PLfR0qhtOKP6eYkUoW7DH8qdjwEyQnsbPJ&index=13

Week 12: The Simulation Argument & The Holographic Hypothesis
• Nick Bostrom’s Simulation Argument Website- http://www.simulation-argument.com
• Nick Bostrom on The Simulation Argument- http://www.youtube.com/watch?v=nnl6nY8YKHs&list=PLfR0qhtOKP6eYkUoW7DH8qdjwEyQnsbPJ&index=24
• David Chalmers’ The Matrix as Metaphysics- http://consc.net/papers/matrix.html
• Leonard Susskind on The World as a Hologram- http://www.youtube.com/watch?v=2DIl3Hfh9tY&list=PLfR0qhtOKP6eYkUoW7DH8qdjwEyQnsbPJ&index=16

Zombies vs Shombies

Richard Marshall, a writer for 3am Magazine, has been interviewing philosophers. After interviewing a long list of distinguished philosophers, including Peter Carruthers, Josh Knobe, Brian Leiter, Alex Rosenberg, Eric Schwitzgebel, Jason Stanley, Alfred Mele, Graham Priest, Kit Fine, Patricia Churchland, Eric Olson, Michael Lynch, Pete Mandik, Eddy Nahmais, J.C. Beal, Sarah Sawyer, Gila Sher, Cecile Fabre, Christine Korsgaard, among others, they seem to be scraping the bottom of the barrel, since they just published my interview. I had a great time engaging in some Existential Psychoanalysis of myself!

Clip Show ‘011

It’s that time of year again! Here are the top posts of 2011 (see last year’s clip show and the best of all time)

–Runner Up– News Flash: Philosophy Sucks!

Philosophy is unavoidable; that is part of why it sucks!

10. Epiphenomenalism and Russellian Monism

Is Russellian Monism committed to epiphenomenalism about consciousness? Dave Chalmers argues that it is not.

9. Bennett on Non-Reductive Physicalism

Karen Bennett argues that the causal exclusion argument provides an argument for physicalism and that non-reductive physicalism is not ruled out by it. I argue that she is wrong and that the causal exclusion argument does cut against non-reductive physicalism.

8. The Zombie Argument Requires Phenomenal Transparency

Chalmers argues that the zombie argument goes through even without an appeal to the claim that the primary and secondary intension of ‘consciousness’ coincide. I argue that it doesn’t. Without an appeal to transparency we cannot secure the first premise of the zombie argument.

7. The Problem of Zombie Minds

Does conceiving of zombies require that we be able to know that zombies lack consciousness? It seems like we can’t know this so there may be a problem conceiving of zombies. I came to be convinced that this isn’t quite right, but still a good post (plus I think we can use the response here in a way that helps the physicalist who wants to say that the truth of physicalism is conceivable…more on that later, though)

6. Stazicker on Attention and Mental Paint

Can we have phenomenology that is indeterminate? James Stazicker thinks so.

5. Consciousness Studies in 1000 words (more) or less

I was asked to write a short piece highlighting some of the major figures and debates in the philosophical study of consciousness for an intro textbook. This is what I came up with

4. Cohen and Dennett’s Perfect Experiment

Dennett’s response to the overflow argument and why I think it isn’t very good

3. My Musical Autobiography

This was big year for me in that I came into possession of some long-lost recordings of my death metal band from the 1990’s as well as some pictures. This prompted me to write up a brief autobiography of my musical ‘career’

2. You might be a Philosopher

A collection of philosophical jokes that I wrote plus some others that were prompted by mine.

1. Phenomenally HOT

Some reflections on Ned Block and Jake Berger’s response to my claim that higher-order thoughts just are phenomenal consciousness

Some Drafts

Here are some recent paper drafts I have been working on, in various stages of being rewritten for various projects. Comments are most welcome!

  • Zombies and Simulation
    • a brief paper arguing that one way to conceive of philosophical zombies is conceiving of a ‘perfect’ simulation of a creature for whom a consciousness-as-biological view is true. Thus physicalists who think of consciousness as biological can admit that zombies are conceivable (even possible) with no consequence to physicalism.
  • The Identity Theory in 2D
    • a short paper sketching an updated version of the type-type identity theory in a two dimensional framework. The resulting view is similar to Lewisian functionalism but combined with a posteriori identities and gives a unified response to all a priori arguments (part of a larger project of taking back a priori reasoning for the physicalist. It seems to me to be a historical accident that a priori arguments are primarily used to argue against physicalism)
  • The Emperor’s New Phenomenology? The Empirical Case for Conscious Experience without First-Order Representations
    • a longer paper written with Hakwan Lau arguing that some kind of higher-order approach to consciousness can make better sense of some key empirical evidence.