readings> zombies and organic logic

Review of Zombies and Consciousness (Robert Kirk, 2005)

Having popularised philosophical zombies in the 1970s, Nottingham University’s Robert Kirk now thinks it is past time to kill them off. But despatching the undead was never going to be easy.

Zombies and Consciousness has two aims. First, Kirk hopes to show that the notion of a zombie – a person of flesh and blood but without the inner light of experience – lacks logical conceivability; it is incoherent and thus cannot be used as grounds for proposing a ‘Hard Problem’ of consciousness.

Second, he wants to go the next step and show that ordinary physicalism can completely account for consciousness. He identifies a set of psychological functions, each of which is plausibly physical in its causation and, when bundled together, should result in a conscious being with no further (mental or otherwise non-physical) aspects left dangling. Consciousness would be just the sum of these material activities and nothing more.

The zombie story is that it is possible to imagine a creature which is exactly the same as you and me in every physical detail. It would have a brain that processes information and act as if it can “see”, “think”, “imagine”, and “feel”. But the final essential ingredient would be missing. It would not benefit from a parade of subjective experiences – qualia. All would be dark inside. Kirk tells how he originally became a zombie enthusiast following a naive question from a first-year student at a tutorial. As he thought about it, the materialist position just melted away and for some years he was an ardent convert.

Zombies do not actually have to exist. Just the fact that we agree the idea to be a logical possibility opens the door to Cartesian dualism. If all the physical circuitry does not necessarily entail the mental states, then physicalism is not up to the job of explaining consciousness. The mind is still the ghost in the machine.

It’s old idea, as Kirk acknowledges. In the 1930s, G.F. Stout used zombie-type examples to argue against epiphenomenalism. Stout said it was “incredible to Common Sense” that there could be human bodies lacking mental experiences that would still go through the motions of making and using telephones and telegraphs, writing and reading books, speaking in Parliament, even arguing about materialism.

For a long time, zombies played only a minor role within consciousness studies. Searle’s Chinese Room – which appealed better to the artificial intelligence community – hogged the limelight. But Chalmers (1996) put zombies centre stage in the late 1990s when he used them to argue that a physicalist approach to mind could never work. The logical conceivability of zombies proved there was an explanatory gap between the objective realm of the brain and the subjective one of mind.

In philosophical circles, however, dualism is a monster that many would like to see buried once and for all. So there would be plenty of people to cheer on Kirk if he has now put paid the zombies that he used to love. Does he succeed?

As a warm up exercise, he starts with the jacket fallacy. Some properties can be imagined as capable of being shrugged off - like a person might remove a jacket. Nothing essential changes. The wearer is merely now sans jacket. However other properties are central to the definition of what it is to be that thing. The performance of a car cannot be altered except by fiddling with some physical part of its machinery. It makes no sense to think of two cars identical in every mechanical detail, yet one has “performance”, and the other lacks it.

Of course this Rylean category-error style rejection of dualism may be considered facile. To zombie-mongers, the performance of a car is merely an emergent property. The mind appears actually different in kind. Stronger arguments are required.

Kirk then mounts his own e-qualia argument (“e” for epiphenomenal the reader is left to presume). His angle is that e-qualia are a necessary corollary of zombiedom. For zombies to exist, e-qualia would also have to exist as the precise type of mental experience that the zombies so sadly lack. And then comes the clever bit. If we feel that his description of these e-qualia is incredible and quite contrary to common sense, the original idea of a zombie must be incredible too. The downfall of one is automatically the demise of the other, for they would be two sides of the same coin.

So what would e-qualia have to be? In the spirit of zombiedom, we would begin with the suggestion that the world has a part that is physical and closed in its causation. That is, every physical event within it is a result of other physical events. This physical part would then be used to construct a body with a brain that does complex cognitive processing. Just like a zombie.

Then along comes the extra bit that makes this creature instead conscious. It would enjoy a parade of non-physical e-qualia. For some reason the physical activity would generate an epiphenomenal, causally inert, glow of experience. The qualia are there but they have no effects and do no cognitive work. This logically is what we must suppose if e-qualia are then to be the kind of thing that can be stripped away without altering the physical activities of a brain in any way.

So Kirk presents us with a conscious being that can be turned into a zombie through the loss of its e-qualia. It all seems conceivable - so far. At this point Kirk hopes to snatch the rug from under the argument. Consciousness involves one further necessary aspect he says. We apparently have epistemic access to our mental states. They are the subject of much noticing, attending, remarking and  comparing.

How, for example, could we ever choose between the taste of two wines unless we had access to qualia that are the subject of the mental contrast? We have no good explanation of this kind of access, he says, but even zombie enthusiasts feel that we possess it. Therefore e-qualia, in the sense of qualia which are so completely epiphenomenal they do not even do indirect work by way of being noticed and acted upon, cannot exist. If this kind of pure epiphenomenalism is inconceivable, as even zombie “ultras” must admit, then zombies become inconceivable as well.

Kirk dismisses the obvious counter-argument. Zombie supporters would reply that zombies are able physically to feign all our complex mental responses. This would be so by definition. They would process a lot of information and give every outward impression of admiring two fine wines. They would fake a sense of attentional effort and deliberation if necessary. So again there would be a dualistic position in which a physical world of itself cannot entail the presence of mental states. The existence of qualia remain extra to any materialistic story.

This misses the point, says Kirk. We know we have access to our conscious states, so the idea of zombies as just us minus e-qualia is the thing that is inconceivable. It is not about what level of clever behavioural simulation might be possible but about whether we really have something inessential that can be stripped away.

Does his argument work? Well not really. Perhaps I am missing something here myself, but it could be true that we really need our mental states to operate and yet it is also conceivable that a zombie might not. This is the essence of the argument. Of course we are actually conscious (we think). But it is unclear how that consciousness is entailed by any physical mechanism.

It is a case of in for a penny, in for a pound. Once we grant that a zombie can feign the presence of everything else, like perception, thought and imagery, then why not also epistemic access? Thus it remains open to us to suppose that we have e-qualia and are merely being fooled by our remarkable cognitive machinery into believing our mental states are both necessary and causal to our intellectual functioning.

Kirk’s case is not helped by his principal follow-up argument, the sole-pictures story (a pun on soul-pictures). He asks us to imagine a zombie whose physical processes produce the particular epiphenomenal effect that it has qualia-type pictures, like little television images, playing on the soles of its feet. Whatever the zombie feigned seeing would in fact show up somewhere as an actual activity. The point is that we would not expect the zombie to have an epistemic relation to this activity merely because it happened to be occurring.

But this is weak. Flickering images projected on the soles of the feet would be a physical process as Kirk himself agrees. And the dualistic position is that, being mental, the epiphenomenal states under discussion are of a different kind. Res cogitans not res extensa. Thus it is not where they show up that matters -– either in the head, or on the feet – but the fact they exist.

So Kirk has not killed off his zombies. Must we then believe in the resulting explanatory gap? Not at all! I would argue that the hard problem is created by a basic assumption of the brand of logic that philosophers generally choose to deploy. Being axiomatic to the logic, this same logic can hardly be used to defeat it.

The arguments of Kirk, Chalmers and others depend on a “mechanical” logic based on the law of the excluded middle. Everything is either a this or a that, one kind of thing or another. Crisp binary divisions are taken for granted. But there is an alternative or indeed complementary view, which I call organic (Kahn, 1960; Peirce. 1980), where middles only become excluded in the course of a process. On this view the question becomes, not how the physical could ever produce the mental, but how they ever became separated.

In the organic view, everything begins mixed together as a vagueness – the unbounded apeiron, or naked Aristotelian potential. Then this vagueness divides dichotomously. It tends towards opposed limits. The Peircean firstness of monadic vagueness becomes the secondness of a dyadic separation through interaction. Then, out of this separating, arises the thirdness, the triadic richness, of hierarchical complexity. A bootstrapping story of 1, 2, 3.

This is not the place to defend organicism as an alternative logic. But we can sketch its key consequences for theories of mind. It implies that every dichotomous outcome begins in the commonality of a vagueness. And the division does not bring absolute separations, only relative ones. Limits arise, but they are limits that can only be approached, never actually reached. To fully attain them would be to break the world apart and leave no middle ground of interaction.

If we follow this logic, which could be said to exude limits rather than exclude middles, we can see that the apparent opposition of mind and matter is in fact an outcome of the dichotomous separation of a single potential. Although the two may now seem far apart as kinds, they must remain connected in terms of causality. They are the mutual product of a process of dependent co-arising or paticca samuppada (Macy, 1991). As a necessary fact of logic, therefore, the physical and the mental are to be regarded as joint products of a process of development. There can be no hard problem because, like figure and ground or yin and yang, one could not exist without the other.

This easy victory does have its troublesome consequences. The same logic requires that all of the physical world must be connected to the mental world in some real manner. This does not necessarily entail panpsychism; the idea that the material world – objects such as stars, rocks and water molecules – has qualia. But it does lead us to pansemiosis, a view of reality organised in a holistic or hierarchical fashion by a top-down, mind-like in the broadest sense, knowing. This is not so outlandish as it may sound. Physics already has universal laws that look down to constrain every local event. Relativity and quantum theory are both observer-dependent models of reality.

For the moment it does not really matter how the concept of mind would be deconstructed under a pansemiotic and organic approach to the modelling of the wider world. It is enough to show that zombies and their detached e-qualia are highly dependent on a system of logic that assumes what it then proves. There is hidden tautology in the arguments of this book as well as in those of zombie enthusiasts.

Mechanical logic is in its way dichotomistic. But because of its reliance on the law of the excluded middle, mechanical logic leaves no option but to say that reality is either dualistic or monadic. Either the world is made of fundamental twonesses – such as chance and necessity, stasis and change, atom and void, discrete and continuous, substance and form, simple and complex, particular and general, matter and mind – or one of these two is taken as the fundamental and the other the derived or constructed.

Every one of the above mentioned dichotomies has been the subject of Hard Problem type wrangling. Is the world fundamentally continuous or discrete, random or determined, a flux or a frozen spacetime block, a formless chora or the shadow cast by Platonic ideas? It is simply the nature of the beast. A discourse founded on the law of the excluded middle has no choice but to vacillate between monism and dualism, finding neither satisfactory when it comes to the deep ontological questions.

So it would be astonishing if Kirk, armed with standard logic, could fulfil his first aim and finally dispose of zombies with the dualism they imply. To start with the physical and then to try to build up to the mental is a doomed project because the connecting middle ground that must bridge the gap has already been excluded in the formation of the dichotomy. Zombies and e-qualia may be incredible to common sense, but dualism remains the inevitable destination for this way of thinking.

The second half of the book is taken up by Kirk’s other aim; an attempt to define consciousness in terms of a bundle of functions. He reviews the rise of awareness in the animal kingdom and says the essence of subjective awareness is being a decider. This ability to decide involves a “basic package” which includes processes such the initiation and control of behaviour, the acquisition, interpretation and retention of information, the assessment of situations, and the choice of alternatives guided by goals.

Then, to ensure this basic package of cognitive skills is conscious, there has to be one final thing – directly active information. What comes into the mind must have immediate impact and gain processing priority. What he is hoping to achieve here is to outline a set of functions which, when combined together, would leave out nothing that a mind is capable of doing. You could hand over this wish list to a clever hardware engineer and get back a conscious system. If his list sounds believably complete and implementable, we should find it easier to accept that mind is material.

Why does this approach seem so inadequate? Again because it is mechanical – based on the atomistic and reductionist approach by which humans build machines. Kirk is saying the mind can be created by putting together a system of particulars. Each of the functions is some particular skill, a component or a module. By careful choice of particulars, a mind can be constructed. An organic metaphysics suggests quite a different approach, for it treats mind as a fundamental category. Mind is an extreme to match that other extreme, brute inanimate matter, and so is a general rather than a particular. It has to be approached in terms of its universal laws rather than as a set of locally contingent specifics.

This is the message we should be taking from the ‘Hard Problem’. The material realm is indeed not enough. Mind is something other. But this does not mean we have to accept dualism. What we have are two limits approached from a shared middle ground. As scientists we should aim to model each kind of limit in terms of universal laws. A heap of particulars would always be the wrong approach for dealing with something that is actually fundamental.

Can mind in fact be treated as a universal? Yes, of course. An organic metaphysics – such as Peircean semiotics, for example – treats mind as the upper boundary, the realm of downward acting constraints. The whole that shapes up the parts. Organicism works as philosophy and it also works as science. Once we know what we are looking for, we can appreciate the progress already made towards modelling the universal laws of mind with anticipatory systems (Grossberg, 1995; Rosen, 1985), autopoietic systems (Maturana and Varela, 1992), complex adaptive systems (Waldrop, 1992), and hierarchy theory (Salthe, 1993; Pattee, 2000). All these approaches share similar principles and lead towards generalised mathematical ideas. And while they have been prompted by the need to explain  (mainly) biological complexity, there is no reason why they cannot be extended to cover physical simplicity – the “simple” world of particles, stars and universes.

This is the future of consciousness studies, in my opinion anyway. We are working towards a theory of how wholes can organise their parts, regardless of whether these wholes are organisms or entire worlds.

Kirk’s zombies are lumps of physics that have lost their minds and no amount of mechanical complexity is ever going to restore them. But the organicist’s idea of mindfulness as the organising, constraining, downwardly-acting, aspect of a dichotomised reality could bring mind back to the entirety of existence. Now that would be quite an achievement for consciousness studies, wouldn’t it?

Robert Kirk's Zombies and Consciousness (Clarendon2005) reviewed by John McCrone for the Journal of Consciousness Studies.

- Chalmers, David (1996), The Conscious Mind (Oxford: Oxford University Press).
Grossberg, Stephen (1995), ‘The attentive brain’, American Scientist, 83(5), pp. 438-449.
- Kahn, Charles (1960), Anaximander and the Origins of Greek Cosmology (New York: Columbia University Press).
- Macy, Joanna (1991), Mutual Causality in Buddhism and General Systems Theory (Albany, NY: State University of New York Press).
- Maturana, Humberto and Varela, Francisco (1992), The Tree of Knowledge (Boston, MA: Shambhala).
- Pattee, Howard (2000), ‘Causation, control, and the evolution of complexity’. In P.B. Anderson, C. Emmeche, N.O. Finnemann and P.V Christiansen (eds.), Downward Causation (Aarhus University Press).
- Peirce, Charles (1980), Selected Writings (Mineola, NY: Dover).
- Rosen, Robert (1985), Anticipatory Systems (New York: Pergamon).
- Salthe, Stanley (1993), Development and Evolution (Cambridge, MA: MIT Press).
- Stout, G.F. (1931), Mind and Matter (Cambridge: Cambridge University Press).
- Waldrop, Mitchell (1992), Complexity (New York: Simon and Schuster).

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