Hexapod BullWhat about Francois Tonneau, then, the other radical externalist who has rallied to Honderich’s side? In his paper he actually positions himself as reviving and improving the stance which was apparently taken by psychological neorealists ninety years ago.

The bedrock of Tonneau’s externalism seems to me to be the same intuition which inspires Honderich and Manzotti: as he says near the beginning of the paper
“ if consciousness is a brain process, then conscious experience cannot have the features that in fact it has, for these features are features of the environment (such as the colours and shapes of surrounding objects).”

That seems to me to confuse features of experience with properties of experience: my experiences don’t have to be red in order to feature red objects. Tonneau, approvingly, quotes Holt decrying the idea of shapeless representations of shape and colourless representations of colour –

“my knowledge is neither shapeless, motionless, colourless, or odourless”.

Well, I rather think it is, actually.But the force of the argument lies mainly in its appeal to the evident difference between riotous phenomenal experience and greyly firing neurons.

Tonneau offers two distinctive ideas. The first, picked up from the earlier theorists he mentions, is that of a cross-section. A cross section is (deep breath) a function of the state of a reference system that takes its values in the environment, the value at any moment being the content. Tonneau very helpfully likens all this to a torch whose beam can pick out various objects depending on which way it is turned: the beam is like the cross-section with the content being whatever object in the environment happens to be illuminated at any one time.

This idea allows Tonneau to deal with a number of objections to externalism. If our consciousness is external, why do changes in our brain affect it, as they clearly do? No problem – for Tonneau, it’s simply as though the torch were being moved around: the change is internal, but it changes the content of something going on out there in the environment, as the beam highlights a different object. In much the same way, it’s easy to explain how people can go on having conscious thoughts while the external world, where their consciousness resides, is static.

You might feel that this line of thinking dilutes Tonneau’s externalism, because it implies that something very important, something which helps determine the contents of consciousness, is actually going on in the reference system – which must surely be on the inside? Personally, I think the proposed set-up works quite nicely except that it incurs the debt of having to assume that all the potential objects of consciousness are actually already out there in the environment.

Tonneau’s second idea helps deal with this commitment, and also provides a way of addressing some even more serious objections: if conscious experience is external, how can we ever dream, or imagine things, or suffer hallucinations? The idea here is that phenomenal properties are higher order features of a person’s path. A path in this sense is the whole series of experiences gone through in the course of the person’s life. So when we imagine something, we are drawing on elements which were in our environment at some point; they may be recombined in a way which gives the appearance of originality and novelty, but they are all drawn from reality. This explains how we manage to think about things we are not experiencing, and it goes some way to explaining how there comes to be such a huge range of potential objects of consciousness apparently just available in the environment.

Not so fast, you may well think: if my conscious experience is external to me, its objects must be around now, mustn’t they? But these objects from my path are all back in the past. You can’t experience things which are no longer present, and indeed may no longer exist. Tonneau’s tactic here (if I’ve understood it right) is connected with the claim that phenomenal qualities are higher order properties. Suppose I saw a blue object last week: the object had the property of being blue, and so my path has the property of containing an object with blue properties. According to Tonneau, that property of containing-an-object-with-blue-properties itself has a property which is the thing I experience now. In fact, that property is the colour we actually experience. Basically, Tonneau uses the temporally-extended nature of the path as a kind of bridge to bring things forward out of the past for us to experience.

This all looks a bit fishy. It seems an odd idea that the colour I see is actually something as abstract as a higher-order property of the totality of my life experiences. I’m not sure the bridge effect really works, either. Actually only part of my path has the property of containing a blue object, and it isn’t the part that’s here now. England contains many churches, but that doesn’t mean that if I can see any part of England I can see churches.

I’m also unconvinced by the idea that the imagination works merely by re-shuffling components derived from our experience. If I think of a purple, six-legged cow, Tonneau would say I’ve put it together from a cow I once saw and past experiences of purpleness, simply adding an extra set of legs. But if I have a purple bovine hexapod in my conscious mind, I don’t just have a cow, a colour, and some legs: I also have the purple, six-legged cow: the theory that consciousness is external surely requires that this legitimate object of thought must itself be out in the environment, not just its separate components? Tonneau believes that his system makes it possible for us to suffer illusions and other non-veridical perceptions, but I don’t think he has succeeded – without a gap between the world and our consciousness, I don’t really see how our perceptions can ever be mistaken.

At times when reading the radical externalists’ arguments, I wonder who they are arguing against. They believe that the majority view is internalist, believing that consciousness resides in the brain, but surely very few people believe that in the straightforward sense. Where is the story of Macbeth? In one sense, in Scotland: in another, in Shakespeare’s manuscript; on stage, in our minds, even in our brains. But in some final, metaphysical sense, stories don’t have a physical location at all, and neither does consciousness. The chief problem with externalism is not so much that it puts consciousness in the wrong place, as that it insists on a location at all.

This point of view is explicitly tackled by Tonneau, along with a number of other objections, but he merely offers reasons why we might be inclined to think our experiences have no location, a response which falls well short of a refutation.

But there’s more to be said yet, and in a little while we’ll see what reception Honderich’s version finally gets in the JCS.

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