Why talk about culture as an evolutionary phenomenon?

Wrapping up my recent working paper, Divergence and Reticulation in Cultural Evolution, has brought that question to the fore.

I’ve been worrying about it for awhile. The alternative, I suppose, is to talk change and to do so with a bunch of individual narratives. Does it make sense to do that with that 3300 node graph that’s been moving in and out of the center of my thought for the last several years? This question, I’m thinking, is mostly about language use, but language use guides intuition, and it’s the intuitions that concern me.

What kinds of objects appear in these historical narratives, and how many? Individual people show up, especially in so-called Great Man accounts. But we also have abstract entities, such as states and cities, and collective entities, such as armies or crowds. And we don’t have all that many of them either, not in any given narrative.

Yes, I know, “all that many” isn’t very specific. All I need from it is that it contrast with 3300 nodes (actually 3346) in Jockers’ graph. On the one I talk about the graph as itself an object, and talk about its properties, and so forth. But it is also clear that, at least in principle, I might want to talk about each and every node in that graph, or, rather, the texts designated by each node. Some of those texts, of course, have received quite a bit of detailed discussion. Others will never get individual attention. And there are those between those extremes that may be discussed for this or that reason – Jockers mentions a few like that.

This property, it seems to me, moves us away from framing our history in terms of a collection of narratives. We’re not going to construct 3346 narratives, one of each text, and then attempt to make various generalizations over those narratives. We’re going to do something else.

We’re going to engage in population thinking, as Ernst Mayer had said. Population thinking doesn’t demand that we think construct narratives for each individual in the population, but it does recognize that each such narrative should be, at least in principle, open and available for inspection. It provides ways of talking about and analyzing the population as a collectivity that is open to the uniqueness of each individual in the collectivity.

That’s what evolutionary thinking is about. The concepts of evolutionary thinking were created for, have evolved for, the purpose of treating collectivities in this way. They are thus quite different from the concepts employed in conventional historical narratives.

Of course, we can think of an evolutionary account as a kind of narrative, which it is. And once we do that, we must then ask, what kinds of narratives are there? That question is outside the scope of this post.

Divergence and Reticulation in Cultural Evolution: Some draft text for an article in progress [#DH]

That's the title of my latest working paper. You can download it here: https://www.academia.edu/41095277/Divergence_and_Reticulation_in_Cultural_Evolution_Some_draft_text_for_an_article_in_progress.

And you can participate in a discussion of it here: https://www.academia.edu/s/9b97738023.

Abstract, Contents, and introductory material below.

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Abstract: In a recent review of articles in computational criticism Franco Moretti and Oleg Sobchuk bring up the issue of tree-like (dendriform) vs. reticular phylogenies in biology and pose the question for the form taken by the evolution of cultural objects: How is cultural information transmitted, vertically (leading to trees) or horizontally (yielding webs)? Dendriform phylogenies are particularly interesting because one can infer the phylogenetic history of an ensemble of species by examining the current state. The horizontal transmission of information in webs obscures any historical signal. I examine a few cultural examples in some detail, including jazz styles and natural language, and then take up the 3300 node graph Matthew Jockers (Macroanalysis 2013) used to depict similarity relationships between 3300 19th century Anglophone novels. The graph depicts a web-like mesh of texts but, uncharacteristically of such patterns, also exhibits a strong historical signal. (Just how that is possible is the subject of another draft.)

Contents

What’s Up? 1

The need for theory: Cultural evolution 2

Trees, Nets, and Inheritance in Biology 4

Divergence and reticulation in culture 7

What kind of objects are we dealing with? 12

Jockers’ Graph, a reticulate network 18

Appendix: A quick guide to cultural evolution 22

 

What’s Up?

In the past year we have had two reviews of recent work in computational criticism:

Nan Z. Da, The Computational Case against Computational Literary Studies, Critical Inquiry 45, Spring 2019, 601-639.

Franco Moretti and Oleg Sobchuk, Hidden in Plain Sight: Data Visualization in the Humanities, New Left Review 118, July August 2019, 86-119.

Though both are critical of that work, they are quite different in tone and intent. Da is broadly dismissive and sees little value in it. Moretti and Sobchuk see considerable value in the work, but are disappointed that it is largely empirical in character, failing to articulate a theoretical superstructure that deepens our understanding of literary history.

I’ve been working on a critique of those papers which seems to have expanded into a primer on thinking about literary culture as an evolutionary phenomenon. I’m currently imaging that the final article will have five parts:

1. Genealogy in literary history
2. Unidirectional trends in cultural evolution
3. Jockers’ Graph: Direction in the 19th century Anglophone novel
4. Expressive culture as a force in history
5. A quick guide to cultural evolution for humanists

I have already posted draft material for the second part of the article, which centers on a graph from Matthew Jockers’ Macroanalysis (2013) [1].

That graph was my central concern from the beginning. It is the most interesting conceptual object I’ve seen in computational criticism, but it is easily misunderestimated and glossed over – as far as I know Da’s understandable but unfortunate dismissal is the only treatment of it in the referred literature. The problem, it seems to me, is that a proper appreciation of it requires a conceptual framework that doesn’t exist in the literature. My objective, then, is to begin assembling such a framework.

Moretti and Sobchuk didn’t mention it at all as their review was confined to journal articles. But it merits consideration in a framework that did establish in their review, if only barely. The invoke a distinction from evolutionary biology, that between tree-like (dendriform) phylogenies and free-form or web-like phylogenies, and suggest that it is important for understanding the relationship between literary for and history (pp. 108 ff.). Jockers graph is web-like network of texts but it exhibits an important feature of dendriform phylogenies, it displays a strong temporal signal. Thus a discussion of issues raised by Moretti and Sobchuk is a good way to begin constructing the missing conceptual framework.

This document consists of draft material for the discussion, the first part of the planned article, and the fifth part. The fifth part, the appendix is straight forward, and I have included it the end of this document. Once I have discussed the issue of dendriform vs. web-like relationships I introduce Jockers’s graph.

In the second part of the article, unidirectional trends in cultural evolution, I plan to say a few words about time and directionality. I will then take up a number of the examples Moretti and Sobchuk review in their article. While they don’t frame them as evidence for unidirectional trends, that is what they are. From my point of view that’s the most interesting and important aspect of their review, they gather those articles into one place. I will be placing those articles in the context of other work showing unidirectional trends.

I don’t yet know whether I’ll post draft materials on the second and fourth sections before drafting the whole article.

The need for theory: Cultural evolution

Now let us turn to Moretti and Sobchuk. Here is their penultimate paragraph (112-113):

Tree-like, linear, reticulate . . . why should we even care about the shape of cultural history? We should, because that shape is implicitly a hypothesis about the forces that operate within history; the tentative, intuitive beginning of a theoretical framework. ‘Theories are, even more than laboratory instruments, the essential tools of the scientist’s trade’, wrote Thomas Kuhn over a half century ago; too bad we didn’t heed his advice. Although the crass anti-intellectualism of Wired—‘correlation is enough’, ‘the scientific method is obsolete’—has fortunately remained an exception, what seems to have happened is that, as the amount of quantitative evidence at our disposal was increasing, our attempts at in-depth explanations were losing their strength. Disclaimers, postponements, ad hoc reactions, false modesty, leaving inferences ‘for another day’ . . . such have been, far too often, our inconclusive conclusions.

Ah, “the forces that operate within history”, that’s what we’re after, no? And we’re not going to get there without theory, yes?

I believe that that theory will be about culture as an evolutionary phenomenon. It is clear that both Moretti and Sobchuk believe that as well, but they do not introduce or frame their essay that way. They introduce it as a methodological inquiry into the use of visualization. It is only as the essay unfolds that evolution emerges as an ideational engine parallel to if not quite driving their interest in visualization.

Accordingly it is necessary to make some preliminary remarks about cultural evolution. Work in cultural evolution has blossomed in the last quarter century but:

While humanities and social science scholars are interested in complex phenomena—often involving the interaction between behaviour rich in semantic information, networks of social interactions, material artefacts and persisting institutions—many prominent cultural evolutionary models focus on the evolution of a few select cultural traits, or traits that vary along a single dimension [...]. Moreover, when such models do build in more traits, these typically are taken to evolve independently of one another [...]. Within cultural evolutionary theory, this strategy holds that the dynamics and structure of cultural evolutionary phenomena can be extrapolated from models that represent a small number of cultural traits interacting in independent (or non-epistatic) processes. This kind of strategy licences the modelling of simple trait systems, either with an eye to describing the kinematics of those simple systems, or to illuminate the evolution and operation of mechanisms underpinning their transmission [...]. [2]

Hence, if students of literature want to think about culture as a phenomenon of evolutionary processes, we will not find suitable models and methods in existing work on cultural evolution. Though we certainly need to be aware of and conversant with that work, we are going to have to construct models and methods suitable to our material. That is the primary objective of this essay. To that end, then, I will be introducing a several of examples of work on cultural evolution in other domains.

Biologists, of course, has been developing evolutionary theory over the last half century. While they agree on basic issues, many details are still under contention. When we, then, as students of literary culture set out to adapt evolutionary theory to the analysis of literary phenomena, just what do we take from biological thinking and how do we do it? Various approaches exist in the general cultural literature, but this is hardly the place to sort through them – though I have prepared a brief appendix with pointers into those discussions. What Moretti and Sobchuk seem to have taken over is the distinction between tree-like lineages and more chaotic, network-like lineages. So that’s where I will start.

Where I am going, though, is toward an argument which says that that distinction is a reflection of the mechanisms that underlie the evolutionary process and it is to those mechanisms that we must look in adapting evolutionary theory to the study of human culture. Cultural evolution unfolds though collectivities of human minds, and they give cultural evolution a different texture, if you will, and different large scale patterns.

References

[1] On the direction of literary history: How should we interpret that 3300 node graph in Macroanalysis, Version 2, https://www.academia.edu/40550795/On_the_direction_of_literary_history_How_should_we_interpret_that_3300_node_graph_in_Macroanalysis_Version_2.

[2] Buskell, A., Enquist, M. & Jansson, F. A systems approach to cultural evolution. Palgrave Commun 5, 131 (2019) pp. 4-5, doi:10.1057/s41599-019-0343-5 https://rdcu.be/bVNtP.

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Addendum 12.10.19: Cultural cross pollination is very old:

According to the Seshat team, the data also clearly undermine another of Jaspers’ key claims: that innovation arose independently in the five core societies, which he referred to as “islands of light”. These societies were engaged in a “ton of cross-cultural exchange,” says historian and Seshat project manager Daniel Hoyer at George Brown College in Toronto, Canada. “The Rabbinical tradition and even Plato’s writings aren’t really conceivable without the Zoroastrianism and Egyptian moral ideals and Hittite legalism that went before.”

Why do we need to talk of cultural evolution, specifically, rather than of history considered as a collection of narratives?

I’ve posted about this before, e.g. A short note on why it is important to conceive of culture as giving rise to an evolutionary process. And I continue to think about it, this time prompted by John Lawler.

I’ve got two things to say. First, when we think of culture at the level of nervous systems I think we’re going to have to conceive it as an evolutionary process. Second, even without that it does seem to be at least heuristically convenient to think of culture as more or less coherent force acting in history. Let’s take these in order.

Culture at the neural level

All of human behavior is executed by the nervous system. At some point we’re going to have to think about this at the neural level. I undertook to do that in my book on music, Beethoven’s Anvil (Basic Books 2001). And I was prompted in part by observations by the late Walter Freeman [1].

Drawing on his work in complex neurodynamics, Freeman argued that each brain is unique, and hence we are in some sense epistemically isolated. Music, however, breaks down neural connections and allows them to reform in concert with others, who share in our music making. When we share music with others we become more alike and so better able to interact.

That became the conceptual seed of the argument I made in Chapters 2 and 3 of Beethoven’s Anvil [2] that, when people are making music together, we may consider their nervous systems to be one interlocked physical system in which some signals travel within brains while other travel between brains through the medium of music itself. Subsequently I wrote an essay review of Steve Mithen’s The Singing Neanderthals: The Origins of Music, Language, Mind and Body, where I began extending that argument to language [3]. Though I didn’t quite get this far, the meanings of words, after all, are constantly being negotiated though interactions with others. That’s the only way to keep those meanings stable enough so that they serve as a reliable medium of communication. Still, over time, things drift; that is to say, they evolve.

And so we’re led to a point that Richard Dawkins makes in the second chapter of The Selfish Gene (1976), that stability is the foundation of life and, hence, at the heart of evolution. He finds stability in what he calls replicators (genes in biology, memes in culture). I think we’re better off seeing it in a process. In biology that process is the interactions of genes and phenotypes though action in an environment, which does lead to change over the long term. In culture we find a process involving corresponding entities, though establishing the cultural correlates of those biological entities is tricky – something I discuss at great length in Beethoven’s Anvil and elsewhere [4]. In the short term – which is one thing in biology, something else in human history and culture – this evolutionary process provides stability, but over the long-term it produces change, relatively graduate change.

Food for thought: Surely something like this interactive process must be going on in primate societies to keep individuals in a group ‘in synch’ with one another. I’m thinking particularly of primates that live in so-called fission/fusion societies, where individuals spend most of their time in relatively small groups, but those groups then get together on occasion. How do we keep the smaller groups in synch with one another when the fuse, if only temporarily, with the larger group? I can see this becoming amplified over time so that it comes to ‘coalesce’ around specifically cultural products (remember that apes do have culture, of a sort) and practices – e.g. hand axes, proto-music – and clever apes become proto-humans.

Culture as a useful heuristic

But that neural argument is, for the most part, my own argument, and certainly played no role in the emergence of cultural evolutionary thought in the last quarter of the previous century. Some of that work has been done by experienced biologists – I’m thinking, for example, of Marcus Feldman, Luigi Cavalli-Sforza, and Peter Richerson – and was often empirical in nature. Others have different backgrounds – Robert Boyd is an anthropologist. None of this work involves a cultural theory with parallels to both the gene and the phenotype. That distinction doesn’t exist. And much of the work is empirical in character.

More recently various investigators have taken biological techniques and software for establishing phylogenies and applied them to cultural phenomena such as musical instruments, folk tales, and language. But this doesn’t require conceptualizing culture as an evolutionary phenomenon in any particularly interesting way (which is what I have in mind in the previous section). That is, it seems to me that the empirical work could have done without the evolutionary framing.

So why is it used? I suspect that it’s useful in a loose and metaphoric way. Thinking about populations of individuals and practices is different from thinking about narratives about people, cities, societies, and so forth.

I’ve posted about cultural evolution as a force in history, and subsequently found an article about biological evolution as a play of forces. What I’m thinking is that, whether or not these investigators consciously regard biological evolution as a force or an interplay of forces, they have developed intuitions of that kind and have decided to apply those intuitions to the study of human culture. In doing that they naturally think in terms of cultural evolution even though they don’t have a model of cultural evolution that parallels biological evolution in a ‘deep’ way. They do worry about the parallel, some more than others, but they don’t let that get in the way of empirical investigation.

So, thinking of culture as an evolutionary process has a heuristic value. In the long term, however, I do think this heuristic has to be cashed out in a substantial theoretical model. And that model will be grounded in the nervous system.

References

[1] Walter Freeman, “A Neurobiological Role of Music in Social Bonding, in The Origins of Music, eds. N. L. Wallin, B. Merker, and Steve Brown (Cambridge, MA: MIT Press, 2000), 411-424.

[2] Final drafts of those chapters are available online as Brains, Music and Coupling, https://www.academia.edu/232642/Beethovens_Anvil_Music_in_Mind_and_Culture.

[3] William Benzon, Synch, Song, and Society, Human Nature Review, Vol. 5, 2005: 66-86, download: https://www.academia.edu/19595352/Synch_Song_and_Society.

[4] For the cultural analogue to the biological gene, which I’ve come to call coordinators, see William Benzon, “Rhythm Changes” Notes on Some Genetic Elements in Musical Culture, Signata 6, Annales des Sémiotiques /Annals of Semiotics: Sémiotique de la musique / Music and Meaning. Per Aage Brandt and José Roberto do Carmo Jr., eds. Presses Universitaires Liège, 2015, pp. 271-285, http://www.academia.edu/23287434/_Rhythm_Changes_Notes_on_Some_Genetic_Elements_in_Musical_Culture.

History, Change, Evolution (and Intelligence)

Why then should we talk of language evolution rather than language change? And the same with culture, why evolution rather than change? The reason, I suspect, is that evolution implies memory in a way that change does not. A system that changes may or may not have memory; but a system can only evolve if it has memory. Not necessary perfect or complete memory, but memory. Evolving systems can ‘track’ and learn from their environment in a way that merely changing ones cannot.

Though I’ve been thinking some version of this notion for years – going back to thinking about episodic structure in Dave Hays’s working group in graduate school in the 1970s – the prompt for this most recent version comes from a recent (and rather strange, but interesting) article by Willard McCarty [1]. He’s interested in articulating a properly humanist way of investigating artificial intelligence. He notes (p. 154):

The best, most highly developed example for AI is the rapidly evolving AlphaGo system, designed to play the ancient board-game known as go in Japanese, weiqi in Chinese (Papineau and Black 2001; Fairbairn 2007). AlphaGo’s victories are impressive,11 especially given the antiquity and complexity of the game and the discipline required to master it. The significance for AI, however, is that in the 2017 (AlphaGo Zero) version, it acquired its skill by playing against itself repeatedly, starting off as tabula rasa with no historical knowledge of play beyond the basic rules (Silver, Schrittwieser, and Simonyan 2017), and that in doing so it deployed legal moves that no human player had thought to make in the approximately 2500-year history of the game. Ambitions for the latest algorithm, AlphaZero, are stronger yet: to achieve “superhuman performance in many challenging domains” (Silver, Hubert, and Schrittwieser 2017).

For the question of intelligence that I raise here, these developments are unquestionably important. What they import, however, is not so much a superhuman intelligence but a clearly different kind. However dependent on the rigidly defined rules and structure of this and other games, these developments in AI serve as an existence-proof that, in the lineage of Turing’s provocation, draws attention to possibilities of intelligence in the built world, in conversation with us.

Well, OK. One might reply with some version of “intelligence”. But what would that tell us?

Given McCarty’s insistence on the digital nature of these computing systems (pp. 152-153) I suspect that would be his answer. His opening salvo on that front (152):

The machine we have is a composite of hardware and of software that progresses stepwise in layers, from the circuitry that creates and maintains the crisp binary signals so often assumed to be simply a given, to the ever friendlier, “intuitive” interface that trains as much as reflects the user’s intuition. The low-level details can be left to electrical and software engineers, but this logic survives through all the layers of abstraction and has much to do with how its resources are applied and how we are affected (Evens 2015).

Color me skeptical. A pile of bricks no more determines what one can construct from them than the digital nature of computing machinery dictates the uses to which it can be put [2].

I’m inclined to look elsewhere, to history. When a human learns to play Go, or any other such board game, she enters into the history of game play. One must, of course, play others and they have, in turn, played others, a linkage of playing pairs that extends back in history to the game’s origins. But AlphaZero sidestepped this history. It did not play against humans. It played against itself.

That in itself would have been to little avail if its raw computing capacity – a function of memory size and CPU cycles – didn’t allow it to explore a very large area of the game space in a relatively short period of time. Consequently it was able to reach areas of the space that humans had not explored so had not accumulated into human knowledge of gameplay. The question we must ask, of course, is how it was able to learn from that experience, to accumulate and distill that history into tactics and strategies available in current play. I believe that, however that may be, the underlying digital nature of the computing circuitry is incidental.

To return to my original question, it is the ability to accumulate and distill historical experience (change) that makes a system an evolutionary one. Evolutionary systems must respond to the world, but they are not pushed around by it willy-nilly. 

And that is why we must talk of cultural evolution, beyond and rather than mere cultural change.

References

[1] Willard McCarty, “Modeling, ontology and wild thought: Toward an anthropology of the artificially intelligent,” HAU: Journal of Ethnographic Theory 9, no. 1 (Spring 2019): 147-161, https://doi.org/10.1086/703872.

[2] See the discussion of implementation in William L. Benzon, “Pursued by Knowledge in a Fecund Universe”, Journal of Social and Evolutionary Systems 20(1): 93-100, 1997. https://www.academia.edu/8790205/Pursued_by_Knowledge_in_a_Fecund_Universe.

Cultural evolution conceived dynamically as an interplay of forces.

Lorenzo Baravalle, Cultural evolutionary theory as a theory of forces, Synthese, May 2019, DOI: 10.1007/s11229-019-02247-0. Downloadable Preprint.

Abstract: Cultural evolutionary theory has been alternatively compared to a theory of forces, such as Newtonian mechanics, or the kinetic theory of gases. In this article, I clarify the scope and significance of these metatheoretical characterisations. First, I discuss the kinetic analogy, which has been recently put forward by Tim Lewens. According to it, cultural evolutionary theory is grounded on a bottom-up methodology, which highlights the additive effects of social learning biases on the emergence of large-scale cultural phenomena. Lewens supports this claim by arguing that it is a consequence of cultural evolutionists’ widespread commitment to population thinking. While I concur with Lewens that cultural evolutionists often actually conceive cultural change in aggregative terms, I think that the kinetic framework does not properly account for the explanatory import of population-level descriptions in cultural evolutionary theory. Starting from a criticism of Lewens’ interpretation of population thinking, I argue that the explanatory role of such descriptions is best understood within a dynamical framework—that is, a framework according to which cultural evolutionary theory is a theory of forces. After having spelled out the main features of this alternative interpretation, I elucidate in which respects it helps to outline a more accurate characterisation of the overarching structure of cultural evolutionary theory.

Note: I have, for some time know, been thinking of cultural evolution as a force in history; indeed, as perhaps the single strongest force in history. The thrust of this article is a bit different, but I welcome its formulation of cultural evolution as a theory of forces.

A short note on why it is important to conceive of culture as giving rise to an evolutionary process

On December 1 I posed four questions in the study of cultural evolution, offering short answers for each:

1. What is the target/beneficiary of the evolutionary dynamic?

2. Replication (copying) or (re)construction.

3. Is there a meaningful distinction comparable to the biological distinction between phenotype and genotype?

4. So what? That is to say, what can an evolutionary account of cultural history tell us that isn’t captured in a pile of narratives of the more standard kind?

I want to say a bit more about that fourth question. I have variously argued that cultural evolution is the single most important force in human history. If true, then we can’t understand human history unless we understand cultural evolution.

Specifically we have to understand that cultural evolution is a force. The first time I posed the issue (to myself) I went to the Stanford Encyclopedia of Philosophy and consulted the article on Philosophy of History looking for a list of forces supposed to be operative. There was a section on “Causation in History” that had something about how analytical philosophers thought about “the role of causal ascriptions in historical explanations.” But that said nothing that spoke to my question. I learned as well that this is a “new” philosophy of history that “emphasizes historical narrative rather than historical causation.” That does not sound good. And so it went through the whole article.

Are there no forces in history? What does “force” mean in this context? Surely it must mean something more than a jumble of individual narratives. Indeed, that’s one thing I’m arguing against. Here’s a passage from the SEP article on Cultural Evolution:

One might fear that in the end cultural change, and the influence of cultural change on other aspects of the human species, are best understood through a series of individual narratives. Our brief examination of memetics illustrated this concern. We gain no real explanatory insight if we are told that ideas spread through populations, some more successfully than others. We want to know what makes some ideas fitter than others. And it is not clear that there will be any general rules that can help us to answer this question. In the biological realm we need detailed accounts of local environmental circumstances, species-specific physiology and anatomy, and so forth, to tell us what makes one organic variant fitter than another. Similarly, in the cultural realm we will need to look at local psychological dispositions to explain why some ideas are more likely to spread than others. So any explanatory value to be had from memetics is parasitic on conventional work done in psychology.

Yes, sure, we’ve got all those narratives. But cultural evolution considered as a force is surely more than a pile of individual narratives. And the same for biological evolution.

Should we consider it a force in history, the history of the earth? I should think so. That is, if I’m going to conceive of cultural evolution as a force, I’m going to do the same with biological evolution.

In both these cases, what does it mean to conceive of evolution as a force? In both cases it’s a force acting on and through populations of individuals. What authorizes that we talk of force? That is certainly a matter of (mere) semantics. But it is also one of substance. I’m asserting that evolution plays a (causal) role in the living world that is similar to the roles of gravity, electromagnetic, and strong and weak nuclear forces.

Hmmmm....

I’m (provisionally) willing to think of history as a pile of narratives. Biological and cultural evolution are forces that operate on and through piles of narratives. Of course earth has a prebiotic history. Those narratives could not have been affected by the bio-evolutionary force (much less the cultural EF). And the BEF would have been weak in the beginning, but in time it remade the earth, e.g. the Great Oxygenation Event in which O2 was deposited in the atmosphere. The same with CEF. BEF and CEF thus bring about organization among millions of individual narratives.

And THAT’s what needs to be appropriately conceptualized, that coordination. That’s why we need a concept of force.