06 September 2013

Figure-Ground Reversal

‘Consciousness is irreducible,’ proclaimed John Searle in a recent TED talk. This was just after telling us that we need to learn to think of it as a wholly biological process.

So, let me get this straight – it’s an irreducible biological process. I like John Searle’s manner – the irritable, baggy-trousered old philosopher thing works well for him. He is best known for his Chinese room thought experiment: an argument against the possibility of true artificial intelligence (AI). He used an elaborate metaphor involving Chinese characters written on bits of paper being passed into a locked room where they are interpreted, using a set of logical rules, by a person who does not speak the language. The set of rules also enables the person in the room to respond in kind.

The argument, as you can see, is to do with ‘actual’ understanding. Searle was claiming that there would be no understanding of the language going on within the locked room; ergo, there would be no understanding going on inside even the most sophisticated AI subjected to the Turing test. I’ll admit that I’m a little biased against Searle’s argument, having seen it systematically disassembled by Daniel Dennett, in his book Consciousness Explained, but I don’t think it would be unfair to say that some of Searle’s claims about the nature of consciousness seem to be somewhat lacking in levels.

We know that the phenomenon of consciousness arises from the biological substrate of the brain. It’s a dualistic waste of time to argue otherwise. Searle is clearly frustrated by the endless philosophical debates over its real or illusory nature, and I’m with him on that, but not because I think we must unequivocally brand it as real; I’m frustrated by that debate because I think both words are wrong.

We often forget that there is a vast range of phenomena in the Universe for which we have no semantic classifications: What do you call that feeling of rocks changing shape by the process of erosion? What do you call that sense of thirsty tree root seeking water? You may argue that these examples have nothing to do with human consciousness. Nevertheless, there are all kinds of micro-processes going on inside you that you don’t ‘experience’ directly but which have some kind of teleonomic ‘direction’ to them.

Terrence Deacon’s Incomplete Nature has most recently influenced my thoughts on this. The book is hard going sometimes, but I’m excited by his formalisation of the idea of a kind of ‘figure-ground reversal’ – what may be important about phenomena like consciousness is not what is present but what is absent. It is a theory of constraints: a whirlpool is a phenomenon produced by the constraining of water molecules to follow a range of downward-spiralling trajectories; perhaps consciousness is an inevitable result of constraint of molecules into a very specific biological configuration. What is absent, in both these cases, is the near-infinite range of trajectories and configurations that those molecules might otherwise have followed or taken on.

Deacon’s ‘essential absences’ – ‘absentials’ – resonate with me. I think it is partly because they demonstrate just how inadequate our semantic modes in the consciousness debate have been. It’s also because I like the idea of being an absential rend in the fabric of the not-me Universe. For many, though, talk of essential absence induces a kind of existential trypophobia – an irrational fear of holes – rendering them confused, frightened, or even disgusted by the notion.

So what about the Chinese room? Well, you just fill it with a vast number of people who don’t understand the symbols, give them the correct rules, and set them to work. If it is correctly set up, the room will produce the correct answer. But, surely, the understanding is still missing. Exactly. There are many things missing from this setup – understanding is an essential one of them. It is a kind of phenomenon that is being generated despite its absence as a specific phenomenon. That is why it looks irreducible.

Strange? Yes, very. But cogito ergo sum! I suppose it’s a good enough shorthand for this: something is producing a phenomenon that other somethings producing this phenomenon and the something producing the phenomenon call ‘thinking’. Constraint steers that clumsy definition towards an essentially useful I.

As I am an inveterate reductionist, you might think I should be more concerned about the biological mechanisms that make this possible. Certainly, the mechanisms fascinate me. However, that does not mean that I expect to be able to tap my finger on a screen and say, ‘Look, that’s consciousness right there.’ I may be able to say, ‘Those are the structures from which the state of consciousness emerges’, but that’s not quite the same. Phenomenal states emerge, and they have many different characteristics. Try pinpointing the vorticity in a whirlpool.

Before I am dragged under, I’d better round this off. If this were a letter, I think it would be pleasing to sign it off with a warmly heartfelt...

...absentially, consciously yours,

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