Tuesday, July 2, 2013

The Memetic Mind, Not: Where Dennett Goes Wrong

On the face of it, Dennett and I have very different views about cultural evolution. To be sure, we both believe that Dawkins’s initial insight is valid: that culture is an evolutionary regime unto itself in which the benefits of cultural success accrue to cultural entities, not human individuals or populations. Where Dennett talks only of memes, I make an explicit distinction between memes and a cultural correlate of the phenotype (for which I have yet to adopt a term of art).

While Dennett allows memes to exist both in the external world and in the mind, most of his discussion is about memes in the mind moving from one mind to another. Indeed, I’d be curious to know what Dennett thinks exists in the mind apart from memes; of what, for example, does the neonate’s mind consist of? By contrast, I insist that memes exist in the external world, as observable (and memorable) properties of objects, events, and processes. The cultural correlates of the biological phenotype emerge as mental processes in brains as those brains engage with memes.

We thus have rather, if not utterly, different views about cultural evolution. As I have been thinking these things through, however, I have begun to suspect that our difference is more in how we assign roles in the process of cultural evolution to the mechanisms of human thought and action than in our conception of those mechanisms (though we no doubt have our differences there as well). And that’s the line I wish to investigate in this post. I will concentrate that investigation on a single essay:
From Typo to Thinko: When Evolution Graduated to Semantic Norms [PDF], in Evolution and Culture. Stephen C. Levinson and Pierre Jaisson, eds. The MIT Press: 2006.
All quotations are from that paper.

* * * * *

After some preliminary this and that, Dennett gets down to business, taking up an argument where Dan Sperber (2000) (PDF) distinguishes between true copying and triggered “re-productions.” Sperber’s conditions for true copying are quite strict, too strict Dennett believes. And I’m with Dennett on this. Sperber, in Dennett’s retelling, asks us to consider the difference between copying “a nonsense scribble and a five-pointed star.” We are not good at copying nonsense scribbles. The copies would be poor, and copies of copies would be poorer still. Copies of five-pointed stars would fare much better. In fact, if the original had visible irregularities, some of the copies might be more accurate than the original (p. 138):
However, Sperber maintains, the succession of stars would not really be copies of their predecessors, since the “copyists” would normalize to the recipe for the drawing procedure, ignoring the details of the individual productions. Is Sperber looking at the right level of fineness? Dawkins’s point is that a finite repertoire of such triggered productions is not just a good trick for human beings who want to heighten their transmission fidelity, it is a Good Trick discovered several billion years ago by natural selection. Sperber distinguishes copying from merely triggering the production of a similar effect, but a repertoire of such triggers, called an alphabet, is what makes high-fidelity copying possible, both in cells and in human culture.
I agree with this.

Having introduced the notion of an alphabet into the discussion, Dennett continues with a succession of examples involving language (p. 139):
Suppose Tommy writes the letters “SePERaTE” on the blackboard, and Billy “copies” it by writing “seperate.” Is this copying or triggered reproduction? The normalization to all lower case letters shows that Billy is not slavishly copying Tommy’s chalk marks but rather is being triggered to execute a series of canonical, normalized acts: make an “s”; make an “e,” etc. It is thanks to these letter norms that Billy can “copy” Tommy’s word at all.
Billy, of course, has already internalized the norms for using lowercase and uppercase letters. If this weren’t the case, if Billy were unfamiliar with the conventions of English orthography–perhaps because is unfamiliar with English or perhaps he only speaks it, then he would copy the upper and lowercase forms as Tommy has written them.

This, no doubt, is obvious to you, and having me underline it in this way is tedious and perhaps even insulting. I do this because that’s what I want to concentrate on, what knowledge is in one’s head as one reads a signal (or some other cultural artifact or practice).

Dennett continues on, this time bringing other norms into play, other bits of internalized knowledge, as well us other actors to utilize them:
And he [Billy] does copy Tommy’s spelling error, unlike Molly, who “copies” Tommy by writing “separate,” responding to a higher norm, at the level of word spelling. Sally then goes a step higher, “copying” the phrase “separate butt equal”— all words in good standing in the dictionary—as “separate but equal,” responding to a recognized norm at the phrase level. Can we go higher? Of course. Anybody who, when “copying” the line in a recipe “Separate three eggs and beat the yolks until they form stiff white cones,” would replace “yolks” with “whites,” knows enough about cooking to recognize the error and correct it. Above spelling and syntactic norms are a host of semantic norms as well.
This ‘assent’ to ever more comprehensive norms is the point of Dennett’s essay. He is arguing that this is typical of culture, of memes, but not of biology, of genes. While there are norms in the genetic realm, they are considerably more restricted.

Here Dennett sets out the parallel (p. 139):
DNA has an alphabet—the famous ACGT—and words, the three-letter codons that “spell” the twenty amino acids. In fact, the high fidelity of genetic transmission depends on the subcellular machinery being triggered to “recognize” and “re-produce” a small repertoire of types, whose idiosyncracies, if any, are ignored, not slavishly copied: “make a cytosine,” “make a guanine,” etc. There are error-correcting enzymes as well, but they don’t ascend (as far as we know!) above the level of a spell checker, correcting “typos” by brute template matching against the original.
So far so good. A bit later Dennett tells us:
Put otherwise, DNA error-correcting enzymes have always responded to semantic norms, but just local or proximal semantic norms—make a G—as contrasted to more distal semantic norms—make a codon for asparagine or make some lysozyme or make a protein that blocks serotonin uptake, or even make something that will fight off infection.
And now things get interesting. Once we start talking about making lysozyme we’ve left the realm of DNA replication and are talking about something else, either organismic maintenance or ontogenesis. We’re in the phenotypic realm rather than the genetic realm.

That’s where I have a problem with Dennett. In the linguistic examples, from orthography, to spelling, syntax and semantics, Dennett places the whole bunch in the memetics realm. When he then offers a set of biological examples from, from “make a cytosine” through “make something that will fight off infection”, he sets them in parallel with his linguistic series, but fails to acknowledge that his biological examples span two spheres, that of genes and that of phenotypes. I want to make a similar distinction in the linguistic bunch, placing the most localized cases in the memetic realm (upper vs. lower case, perhaps spelling) and the rest in a different realm, whatever you want to call the cultural correlate of biological phenotypes.

Dennett sees the argument he developed in the linguistic example as being completely general (pp. 141-142):
When Sperber notes that in cultural transmission “the information provided by the stimulus is complemented with information already in the system” (2000: 171) he is right, but the same is true of DNA replication. The main difference, so far as I can see, is that unlike DNA replication, human cultural replication is accomplished by processes of highly variable semantic depth, responding to perceived (and misperceived) “copying” errors relative to norms at many levels. The alphabets of written languages provide us with the most vivid and best-understood system of such norms of replication, but the phenomenon of semantic norms is not directly tied to language. Musical notation relies on the staff to digitalize the roughly inked spots, so that a musician can see at a glance that a chord is A-C#-E-G even though the A is written almost twice as far beneath the staff as it is “supposed” to be. A sketch of a new sort of axle for a wagon need not make the wheels exactly round; the user of the sketch will recognize those irregular closed curves as representations of wheels, which are to be round, of course. As we move through our various apprenticeships in life, we learn to perceive new families of categories—new alphabets, in an extended sense—from which to construct high-fidelity copies. Only a skilled potter can see at a glance what another potter is doing and copy it or teach it to others.
While I believe he is correct in insisting upon the generality, I also think that, in every case, he needs to distinguish between memetic ‘triggers’ and the complex cascade of mental activity that swirls around them. In my view the memetic triggers are out there in the physical world, they are the properties of things, events, and processes. The mental swirls and eddies, they are the cultural phenotypes, the cultural interactors. These are the entities that on which cultural selection operates.

And THAT’s why I am insisting, that in reasoning about cultural evolution, we must distinguish between memetic realm and some other realm, the realm of cultural phenotypes. Frankly, I’m sorely tempted simply to call this other realm by a common name, the mind or the mental realm. But won’t, not just yet.

THAT was just a sudden impulse, one whose implications I’ve not had time to consider. But, given Dennett’s propensity to view the mind as a stew of memes, that’s a terminological matter that would but our difference quite clearly.

I also realize that, at this point, I’ve not really argued my case, not in this post, though I’ve certainly argued it elsewhere. And I’ll argue it some more. But not here and not now.

More later.

* * * * *

I drafted the body of this post yesterday, July 1, but wrote the introductory paragraphs this morning (July 2). You may notice that in the second paragraph I suggest that the cultural correlates of biological phenotypes are mental entities. I’m still liking that usage. But such things require more than a day to simmer.

Addendum, 3 July: Over at Replicated Typo, Tim Tyler points out that Dennett has acknowledged a phenotypic component in cultural evolution. A 1998 draft says this:
Memes are supposed to be analogous to genes, the replicating entities of the cultural media, but they also have vehicles, or phenotypes; they are like not-so-naked genes. They are like viruses (Dawkins, 1993). As with viruses, there is a phenotype/genotype distinction, but just barely. Basically, a virus is just a string of DNA (or RNA) with attitude. And similarly, a meme is an information-packet (the information, not the vehicle) with attitude--with some phenotypic clothing that has differential effects in the world that thereby influence its chances of getting replicated.
The paper I'm working from in this post, which is more recent (drafted in 2000, published in 2006), is as close as Dennett gets to a detailed discussion of mechanisms. That's where one would expect some discussion of cultural phenotypes, he yet says nothing about them. He doesn't mention them in his 2009 Cold Spring Harbor paper, which would have been for a technical audience, nor in his 2010 encyclopedia article. I can only conclude that, as far as he's concerned, they are of no account. That's a major slip-up on his part.

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