Give up on real comprehension, says Daniel Dennett in From Bacteria to Bach and Back: commendably honest but a little discouraging to the reader? I imagine it set out like the warning above the gates of Hell: ‘Give up on comprehension, you who turn these pages’. You might have to settle for acquiring some competences.
What have we got here? In this book, Dennett is revisiting themes he developed earlier in his career, retelling the grand story of the evolution of minds. We should not expect big new ideas or major changes of heart ( but see last week’s post for one important one). It would have been good at this stage to have a distillation; a perfect, slim little volume presenting a final crystalline formulation of what Dennett is all about. This isn’t that. It’s more like a sprawling Greatest Hits album. In there somewhere are the old favourites that will always have the fans stomping and shouting (there’s some huffing and puffing from Dennett about how we should watch out because he’s coming for our deepest intuitions with scary tools that may make us flinch, but honestly by now this stuff is about as shocking and countercultural as your dad’s Heavy Metal collection); but we’ve also got unnecessary cover versions of ideas by other people, some stuff that was never really a hit in the first place, and unfortunately one or two bum notes here and there.
And, oh dear, another attempt to smear Descartes by association. First Dennett energetically promoted the phrase “Cartesian theatre” – so hard some people suppose that it actually comes from Descartes; now we have ‘Cartesian gravity’, more or less a boo-word for any vaguely dualistic tendency Dennett doesn’t like. This is surely not good intellectual manners; it wouldn’t be quite so bad if it wasn’t for the fact that Descartes actually had a theory of gravity, so that the phrase already has a meaning. Should a responsible professor be spreading new-minted misapprehensions like this? Any meme will do?
There’s a lot about evolution here that rather left me cold (but then I really, really don’t need it explained again, thanks); I don’t think Dennett’s particular gift is for popularising other people’s ideas and his take seems a bit dated. I suspect that most intelligent readers of the book will already know most of this stuff and maybe more, since they will probably have kept up with epigenetics and the various proposals for extension of the modern synthesis that have emerged in the current century, (and the fascinating story of viral intervention in human DNA, surely a natural for anyone who likes the analogy of the selfish gene?) none of which gets any recognition here (I suppose in fairness this is not intended to be full of new stuff). Instead we hear again the tired and in my opinion profoundly unconvincing story about how leaping (‘stotting’) gazelles are employing a convoluted strategy of wasting valuable energy as a lion-directed display of fitness. It’s just an evasive manoeuvre, get over it.
For me it’s the most Dennettian bits of the book that are the best, unsurprisingly. The central theme that competence precedes, and may replace, comprehension is actually well developed. Dennett claims that evolution and computation both provide ‘inversions’ in which intentionless performance can give the appearance of intentional behaviour. He has been accused of equivocating over the reality of intentionality, consciousness and other concepts, but I like his attitude over this and his defence of the reality of ‘free-floating rationales’ seems good to me. It gives us permission to discuss the ‘purposes’ of things without presupposing an intelligent designer whose purposes they are, and I’m completely with Dennett when he argues that this is both necessary and acceptable. I’ve suggested elsewhere that talking about ‘the point’ of things, and in a related sense, what they point to, is a handy way of doing this. The problem for Dennett, if there is one, is that it’s not enough for competence to replace comprehension often; he needs it to happen every time by some means.
Dennett sets out a theoretical space with ‘bottom-up vs top-down’, ‘random vs directed search’, and ‘comprehension’ as its axes; at one corner of the resulting cube we have intentionless structures like a termite colony; at the other we have fully intentional design like Gaudi’s church of the Sagrada Familia, which to Dennett’s eye resembles a termite colony. Gaudi’s perhaps not the ideal choice here, given his enthusiasm for natural forms; it makes Dennett seem curiously impressed by the underwhelming fact that buildings by an architect who borrowed forms from the natural world turn out to have forms resembling those found in nature.
Still, the space suggests a real contrast between the mindless processes of evolution and deliberate design, which at first sight looks refreshingly different and unDennetian. It’s not, of course; Dennett is happy to embrace that difference so long as we recognise that the ‘deliberate design’ is simply a separate evolutionary process powered by memes rather than genes.
I’ve never thought that memes, Richard Dawkins’s proposed cultural analogue of genes, were a particularly helpful addition to Dennett’s theoretical framework, but here he mounts an extended defence of them. One of the worst flaws in the theory as it stands – and there are several – is its confused ontology. What are memes – physical items of culture or abstract ideas? Dennett, as a professional philosopher, seems more sensitive to this problem than some of the more metaphysically naive proponents of the meme. He provides a relatively coherent vision by invoking the idea that memes are ‘tokens’; they may take all sorts of physical forms – written words, pictures, patterns of neuronal firing – but each form is a token of a particular way of behaving. The problem here is that anything at all can serve as a token of any meme; we only know that a given noise or symbol tokens a specific meme because of its meaning. There may be – there certainly are – some selective effects that bite on the actual form of particular tokens. A word that is long or difficult to pronounce is more likely to be forgotten. But the really interesting selections take place at the level of meanings; that requires a much more complex level of explanation. There may still be mechanisms involved that are broadly selective if not exactly Darwinian – I think there are – but I believe any move up to this proper level of complexity inevitably edges the simplistic concept of the meme out of play.
The original Dawkinsian observation that the development of cultural items sometimes resembles evolution was sound, but it implicitly called for the development of a general theory which in spite of some respectable attempts, has simply failed to appear. Instead, the supporters of memetics, perhaps trapped by the insistent drumbeat of the Dawkinsian circus, have tended to insist instead that it’s all Darwinian natural selection. How a genetic theory can be Darwinian when Darwin never heard of genes is just one of the lesser mysteries here (should we call it ‘Mendelian’ instead? But Darwin’s name is the hooray word here just as Descartes’ is the cue for boos). Among the many ways in which cultural selection does not resemble biological evolution, Dennett notes the cogent objection that there is nothing that corresponds to DNA; no general encoding of culture on which selection can operate. One of the worst “bum notes” in the book is Dennett’s strange suggestion that HTML might come to be our cultural DNA. This is, shall we say, an egregious misconception of the scope of text mark-up language.
Anyway, it’s consciousness we’re interested in (check out Tom Clark’s thoughtful take here) and the intentional stance is the number the fans have been waiting for; cunningly kept till last by Dennett. When we get there, though, we get a remix instead of the classic track. Here he has a new metaphor, cunningly calculated to appeal to the youth of today; it’s all about apps. Our impression of consciousness is a user illusion created by our gift for language; it’s like the icons that activate the stuff on your phone. You may object that a user illusion already requires a user, but hang on. Your ability to talk about yourself is initially useful for other people, telling them useful stuff about your internal states and competences, but once the system is operating, you can read it too. It seems plausible to me that something like that is indeed an important part of the process of consciousness, though in this version I felt I had rather lost track of what was illusory about it.
Dennett moves on to a new attack on qualia. This time he offers an explanation of why people think they occur – it’s because of the way we project our impressions back out into the world, where they may seem unaccountable. He demonstrates the redundancy of the idea by helpfully sketching out how we could run up a theory of qualia and noting how pointless they are. I was nodding along with this. He suggests that qualia and our own sense of being the intelligent designers in our own heads are the same kind of delusion, simply applied externally or internally. I suppose that’s where the illusion is.
He goes on to defend a sort of compatibilist view of free will and responsibility; another example of what Descartes might be tempted to label Dennettian Equivocation, but as before, I like that posture and I’m with him all the way. He continues with a dismissal of mysterianism, leaning rather more than I think is necessary on the interesting concept of joint understanding, where no one person gets it all perfectly, but nothing remains to be explained, and takes a relatively sceptical view of the practical prospects for artificial general intelligence, even given recent advances in machine learning. Does Google Translate display understanding (in some appropriate sense); no, or rather, not yet. This is not Dennett as we remember him; he speaks disparagingly of the cheerleaders for AI and says that “some of us” always discounted the hype. Hmm. Daniel Dennett, long-time AI sceptic?
What’s the verdict then? Some good stuff in here, but as always true fans will favour the classic album; if you want Dennett at his best the aficionado will still tell you to buy Consciousness Explained.