An Inquiry into & a Critique of Dennett on Intentional Systems

A new working paper. Downloads HERE:

Abstract, contents, and introduction below:

* * * * *

Abstract: Using his so-called intentional stance, Dennett has identified so-called “free-floating rationales” in a broad class of biological phenomena. The term, however, is redundant on the pattern of objects and actions to which it applies and using it has the effect of reifying the pattern in a peculiar way. The intentional stance is itself a pattern of wide applicability. However, in a broader epistemological view, it turns out that we are pattern-seeking creatures and that phenomenon identified with some pattern must be verified by other techniques. The intentional stance deserves no special privilege in this respect. Finally, it is suggested that the intentional stance may get its intellectual power from the neuro-mental machinery it recruits and not from any special class of phenomena it picks out in the world.

CONTENTS

Introduction: Reverse Engineering Dan Dennett 2
Dennett’s Astonishing Hypothesis: We’re Symbionts! – Apes with infected brains 6
In Search of Dennett’s Free-Floating Rationales 9
Dan Dennett on Patterns (and Ontology) 14
Dan Dennett, “Everybody talks that way” – Or How We Think 20

Introduction: Reverse Engineering Dan Dennett

I find Dennett puzzling. Two recent back-to-back videos illustrate that puzzle. One is a version of what seems to have become his standard lecture on cultural evolution, this time entitled

https://www.youtube.com/watch?feature=player_embedded&v=AZX6awZq5Z0

As such it has the same faults I identify in the lecture that occasioned the first post in this collection, Dennett’s Astonishing Hypothesis: We’re Symbionts! – Apes with infected brains. It’s got a collection of nicely curated examples of mostly biological phenomenon which Dennett crafts into an account of cultural evolution though energetic hand-waving and tap-dancing.
And then we have a somewhat shorter video that is a question and answer session following the first:

https://www.youtube.com/watch?feature=player_embedded&v=beKC_7rlTuw

I like much of what Dennett says in this video; I think he’s right on those issues.

What happened between the first and second video? For whatever reason, no one asked him about the material in the lecture he’d just given. They asked him about philosophy of mind and about AI. Thus, for example, I agree with him that The Singularity is not going to happen anytime soon, and likely not ever. Getting enough raw computing power is not the issue. Organizing it is, and as yet we know very little about that. Similarly I agree with him that the so-called “hard problem” of consciousness is a non-issue.

How is it that one set of remarks is a bunch of interesting examples held together by smoke and mirrors while the other set of remarks is cogent and substantially correct? I think these two sets of remarks require different kinds of thinking. The second set involve philosophical analysis, and, after all Dennett is a philosopher more or less in the tradition of 20th century Anglo-American analytic philosophy. But that first set of remarks, about cultural evolution, is about constructing a theory. It requires what I called speculative engineering in the preface to my book on music, Beethoven’s Anvil. On the face of it, Dennett is not much of an engineer.

And now things get really interesting. Consider this remark from a 1994 article [1] in which Dennett gives an overview of this thinking up to that time (p. 239):

My theory of content is functionalist […]: all attributions of content are founded on an appreciation of the functional roles of the items in question in the biological economy of the organism (or the engineering of the robot). This is a specifically ‘teleological’ notion of function (not the notion of a mathematical function or of a mere ‘causal role’, as suggested by David LEWIS and others). It is the concept of function that is ubiquitous in engineering, in the design of artefacts, but also in biology. (It is only slowly dawning on philosophers of science that biology is not a science like physics, in which one should strive to find ‘laws of nature’, but a species of engineering: the analysis, by ‘reverse engineering’, of the found artefacts of nature – which are composed of thousands of deliciously complicated gadgets, yoked together opportunistically but elegantly into robust, self-protective systems.)

I am entirely in agreement with his emphasis on engineering. Biological thinking is “a species of engineering.” And so is cognitive science and certainly the study of culture and its evolution.

Earlier in that article Dennett had this to say (p. 236):

It is clear to me how I came by my renegade vision of the order of dependence: as a graduate student at Oxford, I developed a deep distrust of the methods I saw other philosophers employing, and decided that before I could trust any of my intuitions about the mind, I had to figure out how the brain could possibly accomplish the mind’s work. I knew next to nothing about the relevant science, but I had always been fascinated with how things worked – clocks, engines, magic tricks. (In fact, had I not been raised in a dyed-in-the-wool ‘arts and humanities’ academic family, I probably would have become an engineer, but this option would never have occurred to anyone in our family.)

My reaction to that last remark, that parenthesis, was something like: Coulda’ fooled me! For I had been thinking that an engineering sensibility is what was missing in Dennett’s discussions of culture. He didn’t seem to have a very deep sense of structure and construction, of, well, you know, how design works. And here he is telling us he coulda’ been an engineer.

Continue reading “An Inquiry into & a Critique of Dennett on Intentional Systems”

Language Evolution and Levels of Explanation

A somewhat contentious debate among the behavioural sciences is currently underway concerning Mayr’s division of causal explanations in evolutionary theory. Here I’m going to give you a brief rundown of two papers in particular, before I chip in my two-cents about how other insights from the theoretical literature can inform this debate. It seems the discussion is just getting started with respect to cultural evolution, so it’d be interesting to hear other peoples’ comments from either camp.

Over the years, evolutionary theorists have tried to make logical divisions between the kinds of things we can ask about, with a view to making it clear what exactly scientific studies can tell us. A dominant paradigm dividing two levels of causation for biological features we see in the world is Mayr’s distinction between ultimate and proximate causes.  Ultimate causation explains the proliferation of a trait in a population in terms of the evolutionary forces acting on that trait. For example, peahens that prefer peacocks with larger tails (an honest signal of fitness following the handicap principle) will have stronger or more successful offspring, and so this preference proliferates along with larger peacock tails. Proximate causation uses immediate physiological and environmental factors to explain a particular peahen’s penchant for a large-tailed peacock in a mate choice trial, where the signal of the peacock’s large tail elevates the hormone levels in the peahen and copulatory behaviour ensues. Although the behaviour in both of these examples is the same, the levels of explanation are based on different sets of factors.

In Perspectives on Psychological Science last year, a paper by Scott-Phillips, Dickins and West voiced some concerns about these two levels of causation being conflated in the behavioural sciences. In particular, they addressed instances where proximate explanations of traits are being framed as ultimate ones. The paper points specifically to studies of the evolution of cooperation, transmitted culture and epigenetics to illustrate this. Regarding the evolution of cooperation, they point to an instance where ‘strong reciprocity’ (an individual’s propensity to reward cooperative norms and sanction violation of these norms) is purported to be an ultimate explanation of why humans cooperate, rather than a proximate mechanism that enables such cooperation.

Table of proximate and ultimate explanations. For the topic of 'linguistic structure', cultural transmission is listed as a proximate explanation, and the adaptive benefit of cooperative activity through communication is given as an ultimate explanation.,
Table 1 from Scott-Phillips et al. (2011), highlight added.

Among the examples was the feature of linguistic structure (see table 1 from paper above), where several studies pointed to the cultural transmission process as an ultimate explanation of linguistic structure. They suggest that cultural transmission constitutes a proximate process, because it gives the means by which linguistic structure is expressed – and this is how cultural transmission contributes to what the linguistic structure looks like. One analogy might be that the vibrating of my particular vocal cords is a proximate mechanism giving rise, in part, to how my voice sounds, rather than an ultimate explanation of why I vocalise. Since an ultimate account must suggest how a trait contributes to inclusive fitness in order to explain its prevalence in humans, they uncontroversially venture that the ultimate rationale for the ubiquity of linguistic structure is that it greater enables communication (and therefore increases inclusive fitness by enabling cooperative activity).

An opposing view was later published in Science by Laland, Sterelny, Odling-Smee et al., who suggest that the use of Mayr’s division of ultimate and proximate causation is not helpful to all evolutionary investigations, and even hampers progress. The grounds for rejecting Mayr’s paradigm seem to lie largely in what Laland et al. term “reciprocal causation”. That is, that “proximate mechanisms both shape and respond to selection, allowing developmental processes to feature in proximate and ultimate explanations”. After aligning proximate explanations with ontogeny and ultimate explanations with phylogeny, they suggest that what we may have called ultimate and proximate features are no longer sharply delineated, and that these reciprocal processes mean that the source of selection sometimes cannot be separated. They present an idea from the field of evolutionary-developmental biology that, if a developmental process makes some variant of a trait more likely to arise than others, then this proximate mechanism helps to construct an “evolutionary pathway”.

Flow charts presenting alternative processes for Biological evolution, Cultural evolution and Gene-culture coevolution
Figure 2 from Laland et al. (2011)

The paper also highlights developmental plasticity, and gene-environment interaction more broadly (see fig. 2 from paper, above), as a process where reciprocal causation offers an evolutionary explanation conceptually comparable to ultimate causation. Talking specifically on the topic of linguistic structure, they present the debate about whether specific design features of language are attributable to biological or cultural evolution. The paper points out that cultural evolution determines features of linguistic structure – for example, word order – and that the existing word order determines that of future speakers. Indeed, at the Edinburgh LEC we know that transmission by iterated inductive inference under general conditions can explain particular structures in languages. That cultural evolution determines the variation between languages, Laland et al. say, provides evidence that it is an evolutionary force comparable to natural selection (and, therefore, ultimate explanation).

What follows is a collection of my thoughts on the matter, which are (spoiler alert) largely in support of the Scott-Phillips et al. paper. I hope others more experienced in cultural evolution studies than I will contribute their perspective.

It seems to me that there are a few assumptions made in the Laland et al. paper that are not quite in line with how Mayr himself understood the paradigm. Perhaps much can be learned from this debate’s previous incarnation, when Richard C. Francis made similar arguments against the ultimate/proximate distinction in 1990. In his critique, he equated ultimate causation with phylogeny and proximate causation with ontogeny – an approach that was rebuked by Mayr in 1993, who made the point that “all physiological activities are proximately caused, but is a reflex an ontogenetic phenomenon?”. Mayr’s response is actually rather unhelpful in addressing the arguments fully, and this statement is particularly dense. But what he is getting at here is the idea that interaction with the environment that gives rise to adaptive behaviours (such as recoiling instantly from a hot stove) is itself subject to selection, and thus constitutes a proximate explanation of causation. Relatedly, he points out that most components of the phenotype are indeed the result of genetic contribution and interaction with the environment, which has been successfully explored in biology within the traditional theoretical paradigm.

A perhaps more nuanced account of how we can divide the possible explanations of biological phenomena is offered by Tinbergen in his “four questions”, where ultimate explanations are further subdivided into Function (concerning the adaptive solution to a survival problem favoured by natural selection) and Phylogeny, which is a historical account of when the trait arose in the species, and importantly includes processes other than natural selection that give rise to variation – such as mutation, drift and the constraints imposed by pre-existing traits (see blind spot example below). Proximate explanations are further split into Mechanism (immediate physiological/environmental factors causal in how the trait operates in the individual) and Ontogeny (the way in which this trait develops over the lifetime of the individual). As a simple example, here is the paradigm applied to a trait like mammalian vision that I lifted from Wikipedia:
Ultimate
Function: To find food and avoid danger.
Phylogeny: The vertebrate eye initially developed with a blind spot, but the lack of adaptive intermediate forms prevented the loss of the blind spot.
Proximate
Causation: The lens of the eye focuses light on the retina
Ontogeny: Neurons need the stimulation of light to wire the eye to the brain within a critical period (as those awful studies of blindfolded kittens illustrated).
A schematic below, adapted from Tinbergen (1963) shows how these levels of causation may interact with one another, which appears to communicate something roughly comparable to the importance Laland et al. place on “reciprocal causation” in the formation of adaptive variants:

Flow chart showing the interaction of functional, phylogenetic, mechanistic and ontogenetic explanations
Adapted from Tinbergen (1963); Causal Relationships

Applied to the debate outlined above, it would seem that there is no apparent reason that a process of gene-environment interaction – including the cultural environment – can’t itself be subject to selection, or that developmental plasticity itself is not an adaptation in need of an ultimate explanation. It has long been the case that behaviour is no longer understood as either “nature” or “nurture”, but gene-environment interaction, with varying levels of heredity. The “reciprocal causation” suggested in Laland et al.’s paper, is (as they point out) very common in nature; feedback loops are uncontroversial proximate processes in biology. That a proximate process may give rise to a dominant variant of a trait in a population does not explain why it is adaptive, and this points to another problem with the proposing the abandonment of Mayr’s paradigm: a logical division of levels of explanation doesn’t seem to be the sort of thing that can be rendered outdated by empirical evidence. Indeed, claims about the particulars of traits and processes (and languages) themselves are a matter for empirical data – but the theoretical issue about the level of explanation that data is useful for does not itself seem to be subject to empirical findings.

The finding that a proximate process such as cultural transmission gives rise to a trait that is prolific in a population is itself exciting and surprising, and even shows us that the pressure for making language easier to learn gives us adaptive languages to learn; however, it could be argued that it is this process that is adaptive, and that the reason why humans so heavily rely on this process is an ultimate explanation.

One way of resolving these two perspectives may be to place cultural processes that give rise to variation at the level of what Tinbergen labels Phylogenetic (one subset of ultimate) explanation, as it concerns processes which produce some heightened frequency of traits over a language’s history. An explanation at the level of Phylogeny still must make recourse to natural selection at some point, since variants that result from mutation or drift are retained because of their adaptive value (or an adaptive trade-off). This approach may be a problem for the current understanding, which holds that the features resulting from cultural processes are themselves adaptive and therefore comparable to what Tinbergen labels Function.

The problem with this is that calling particular structures of language ‘adaptive’ obscures what it is about Language that is actually being selected for. To flesh out what I mean, I think it’s useful to consult Millikan’s (1993) distinction between Direct Proper Function and Derived Proper Function (… bear with me, it’ll be worth it, honest). The Direct Proper Function of a given trait T can be thought of as a “reproduction” of an item that has performed the exact same adaptive function F, and T exists because of these historical performances of F. Sperber and Origgi (2000) use the illustrative example of the heart, where the human heart has a bunch of properties (it pumps blood, makes a thumping noise, etc), but only its ability to pump blood is its Direct Proper Function. This is because even a heart that doesn’t work right or makes irregular thumping noises or whatever, still has the ability to pump blood. Hearts that pump blood have been “reproduced through organisms that, thanks in part to their owning a heart pumping blood, have had descendents similarly endowed with blood-pumping hearts”.

The Derived Proper Function, however, refers to a trait T that is the result of some device that, in some environment, has a Proper Function F. In that given environment, F is usually achieved by the production of something like T. If I unpack this idea and apply it to language, we can understand it as the acquisiton and production of a device that, in this environment, leads to, say, a particular SVO language, T. The Proper Function of adaptive communication is performed by T in this case, but could also be performed by any number of SOV, VSO, etc Ts in other cases. In other words, the Proper Function of this language is not the word order itself, but communication. The word order is the realisation of this device that is reproduced because of the performance of T in a particular environment, but does not necessarily lead to T in the next incarnation of that device (i.e. My child, if born and raised in Japan, will speak Japanese). We see, then, that a proximate process resulting in what a particular language spoken by a given population looks like does not necessarily speak to the evolutionary function. In other words, it is the device that allows the performance of Language that is adaptive, not the individual language itself.

One question being asked in the study of cultural transmission is why a particular language looks like it does, while we also know that there are 6000 different versions that perform the same (ultimate) function. I would even argue that asking how proximate processes shape languages is actually the most exciting and interesting avenue of inquiry precisely because it’s so blindingly obvious what the adaptive function of language is. But perhaps the value in this endeavour is somewhat neglected, in part, because of the same impression that Francis (1990) had: “the attitude, implicit in the term ultimate cause, [is] that these functional analyses are somehow superordinate to those involving proximate causes” which would be a shame. It seems to me that the coarse grain of ultimate vs proximate perhaps doesn’t do enough to help complex proximate study to position itself in the wider theoretical framework, and the best way to proceed from this might be to couch explanation in terms of Function, Phylogeny, Ontogeny and Mechanism. I think more fine-grained terminology grants us more explanatory power, in this case.

A final question in this debate that came up too many times during discussions with the LEC is: what does keeping the traditional paradigm “buy us”? Well, the first answer to this is consilience with one of the most successful and robust theories in science. The same sentiment has been communicated by Pinker and Bloom (1990), who said: “If current theory of language is truly incompatible with the neo-Darwinian theory of evolution, one could hardly blame someone for concluding that it is not the theory of evolution that must be questioned, but the theory of language”. Part of the reason this debate may have arisen is that studies of cultural evolution have used evolutionary theory as an incredibly fruitful way of analysing cultural processes, but additional acknowledgement about how cultural adaptation is different to biological adaptation may be necessary. This difference is an aspect of Laland’s paper (shown in Fig 2) that I think is important, as it’s part of the reason that more nuanced frameworks for cultural evolution are now needed. Without this widespread acknowledgement, cultural evolution may be considered an extension of biological evolutionary theory instead of a successfully applied metaphor. It seems to me that the side of this debate one falls on is well predicted by whether one subscribes to the former interpretation of cultural evolution or the latter.

Knowing which level of explanation current work pertains to is a valuable part of evolutionary exploration, and abandoning this in favour of an approach where proximate processes are explanatory ends to themselves may mean the exploration of Function and Phylogeny may suffer. That said, it is telling, I think, that even in seeking to abandon the proximate/ultimate distinction, we must still exploit this existing terminology in order to explain such a position. That natural selection has explained countless adaptations in all living things is certainly not trivial, and to reject the theory giving rise to ultimate explanations as they’re currently defined is to reject this fundamental aspect of evolutionary theory. The big problem seems to be that we’re coming to understand proximate processes as so elaborate and complex, that a more nuanced framework is needed to deal with the dynamics of those processes. I reckon, however, that such a framework can be developed within the traditional paradigms of evolutionary theory.

 

References

Francis, R.C. (1990) – “Causes, Proximate and Ultimate” Biology and Philosophy 5(4) 401-415.

Laland, K., Sterelny, K., Odling-Smee, J., Hoppitt, W. & Uller, T. (2011) – “Cause and Effect in Biology Revisited: Is Mayr’s Proximate-Ultimate Distinction Still Useful?” Science 334, 1512-1516.

Mayr, E. (1993) – “Proximate and Ultimate Causations” Biology and Philosophy 8: 93-94.

Millikan, R. (1993) – White Queen Psychology and Other Essays for Alice, Cambridge, Mass: MIT Press.

Pinker, S. & Bloom, P. (1990) – “Natural language and natural selection” Behaviour and Brain Sciences 13, 707-784.

Scott-Phillips, T. Dickins, T. & West, S. (2011) – “Evolutionary Theory and the Ultimate-Proximate Distinction in the Human Behavioural Sciences” Perspectives on Psychological Science 6(1): 38-47.

Sperber, D. & Origgi, G. (2000) – “Evolution, communication and the proper function of language” In P. Carruthers and A. Chamberlain (Eds.) Evolution and the Human Mind: Language, Modularity and Social Cognition (pp.140-169) Cambridge: Cambridge University Press.

Tinbergen, N. (1963) “On Aims and Methods in Ethology,” Zeitschrift für Tierpsychologie, 20: 410–433.

 

 

Cultural differences in lateral transmission: Phylogenetic trees are OK for Linguistics but not biology

The three areas under analysis

An article in PLos ONE debunks the myth that hunter-gatherer societies borrow more words than agriculturalist societies. In doing so, it suggests that horizontal transmission is low enough for phylogenetic analyses to be a valid linguistic tool.

Lexicons from around 20% of the extant languages spoken by hunter-gatherer societies were coded for etymology (available in the supplementary material). The levels of borrowed words were compared with the languages of agriculturalist and urban societies taken from the World Loanword Database.  The study focussed on three locations:  Northern Australia, northwest Amazonia, and California and the Great Basin.

In opposition to some previous hypotheses, hunter-gatherer societies did not borrow significantly more words than agricultural societies in any of the regions studied.

The rates of borrowing were universally low, with most languages not borrowing more than 10% of their basic vocabulary.  The mean rate for hunter-gatherer societies was 6.38% while the mean for 5.15%.  This difference is actually significant overall, but not within particular regions.  Therefore, the authors claim, “individual area variation is more important than any general tendencies of HG or AG languages”.

Interestingly, in some regions, mobility, population size and population density were significant factors.  Mobile populations and low-density populations had significantly lower borrowing rates, while smaller populations borrowed proportionately more words.  This may be in line with the theory of linguistic carrying capacity as discussed by Wintz (see here and here).  The level of exogamy was a significant factor in Australia.

The study concludes that phylogenetic analyses are a valid form of linguistic analysis because the level of horizontal transmission is low.  That is, languages are tree-like enough for phylogenetic assumptions to be valid:

“While it is important to identify the occasional aberrant cases of high borrowing, our results support the idea that lexical evolution is largely tree-like, and justify the continued application of quantitative phylogenetic methods to examine linguistic evolution at the level of the lexicon. As is the case with biological evolution, it will be important to test the fit of trees produced by these methods to the data used to reconstruct them. However, one advantage linguists have over biologists is that they can use the methods we have described to identify borrowed lexical items and remove them from the dataset. For this reason, it has been proposed that, in cases of short to medium time depth (e.g., hundreds to several thousand years), linguistic data are superior to genetic data for reconstructing human prehistory “

Excellent – linguistics beats biology for a change!

However, while the level of horizontal transmission might not be a problem in this analysis, there may be a problem in the paths of borrowing.  If a language borrows relatively few words, but those words come from many different languages, and may have many paths through previous generations, there may be a subtle effect of horizontal transition that is being masked.  The authors acknowledge that they did not address the direction of transmission in a quantitative way.

A while ago, I did study of English etymology trying to quantify the level of horizontal transmission through time (description here).  The graph for English doesn’t look tree-like to me, perhaps the dynamics of borrowing works differently for languages with a high level of contact:

Claire Bowern, Patience Epps, Russell Gray, Jane Hill, Keith Hunley, Patrick McConvell, Jason Zentz (2011). Does Lateral Transmission Obscure Inheritance in Hunter-Gatherer Languages? PLoS ONE, 6 (9) : doi:10.1371/journal.pone.0025195

Academic Networking

Who are the movers and shakers in your field?  You can use social network theory on your bibliographies to find out:

Today I learned about some studies looking at social networks constructed from bibliographic data (from Mark Newman, see Newman 2001 or Said et al. 2008) .  Nodes on a graph represent authors and edges are added if those authors have co-authored a paper.

I scripted a little tool to construct such a graph from bibtex files – the bibliographic data files used with latex.  The Language Evolution and Computation Bibliography – a list of the most relevant papers in the field – is available in bibtex format.

You can look at the program using the online Academic Networking application that I scripted today, or upload your own bibtex file to find out who the movers and shakers are in your field.  Soon, I hope to add an automatic graph-visualisation, too.

Continue reading “Academic Networking”

Bored birds, busy brains: Habituation to song initiates significant molecular changes in auditory forebrain of zebra finch

When we think of habituation, we tend to think of a process in which there is a decrease in psychological and behavioural response(s) over time following an organism’s exposure to a stimulus. Conceptualising habituation in this manner seems to imply the loss of something once an initial learning event has taken place. Although this may accurately describe what occurs at the psychological and behavioural levels, a study by a group of scientists from the University of Illinois (Dong et al. 2010), which examines habituation at the neurobiological level, shows that contrary to this conceptualisation, both initial exposure and habituation to song playbacks initiates a vast array of genetic activity in the zebra finch brain.

The systematic regulation of FoxP2 expression in singing zebra finches has been the subject of previous posts, but there is also a growing literature, of which Dong et al’s study is a part, documenting increases in ZENK gene (which encodes a transcription factor protein that in turn regulates the expression of other target genes) expression in zebra finch auditory forebrain areas in response to playbacks of song or the song of a conspecific. Studies showed that ZENK expression seems to mirror the typical decline in response associated with habituation in that after a certain amount of repetition, presentation of the song that originally elicited upregulation of ZENK no longer did so, and that ZENK returned to baseline levels – although upregulation of ZENK would occur if a different song or an aspect of novelty was introduced (i.e. the original song was presented in a different visual or spatial context).

What Dong et al. have demonstrated by conducting a large scale analysis of gene expression at initial exposure, habituation, and post-habituation stages however, is that unexpectedly profound genetic changes occur as a result of habituation in the absence of any additional novel stimuli following the surge of activity observed during initial exposure to novel song. Thus, the resounding merits of the Dong et al. (2010) study lie in the broadness of their approach, providing a true sense of magnitude with respect to genomic involvement in vocal communication and illuminating important influences that have gone unnoticed by studies with a narrower focus. I summarise the experimental design and findings of the paper below.

Continue reading “Bored birds, busy brains: Habituation to song initiates significant molecular changes in auditory forebrain of zebra finch”

The Bog

If you like wading through deposits of dead animal material, then you should go over and visit Richard Littauer’s new blog, The Bog. Having been exposed to his writings on both this blog, and through the Edinburgh language society website, I’m sure it will be worth a visit — for good writing, if not for your dire need to distinguish between forest swamps and shrub swamps. His first post is on Mung, the colloquial name for Pylaiella littoris, which is apparently a common seaweed. Here is his quick overview of the blog:

So, The Bog is going to be the resting place for various studies and explorations. Richard Littauer is the writer; he is working on his MA in Linguistics at Edinburgh University. He writes about evolutionary linguistics and culture at Replicated Typo, about general linguistic musings at a non-academic standard at Lang. Soc., about constructed languages on Llama, and about various philosophical things at Pitch Black Press. Since none of these blogs were a perfect fit for the scientific equivalent of a swamp-romp through subjects he doesn’t study, he set up this blog. Expect posts about ecology, biology, linguistics, anthropology, or anything in between.

The fact that it’s called the Bog has nothing to do with the British slang for ‘bathroom’. Rather, Richard (well, I) have an affinity with swamps for some unexplained reasons. Expect posts on swamps.

If that doesn’t appeal to you, then Richard is also well-known for being the world’s number one Na’vi fan.

From Natyural to Nacheruhl: Utterance Selection and Language Change

Most of us should know by now that language changes. It’s why the 14th Century prose of Geoffrey Chaucer is nearly impenetrable to modern day speakers of English. It is also why Benjamin Franklin’s phonetically transcribed pronunciation of the English word natural sounded like natyural (phonetically [nætjuɹəl]) rather than our modern variant with a ch sound (phonetically [nætʃəɹəl]). However, it is often taken for granted on this blog that language change can be understood as an evolutionary process. Many people might not see the utility of such thinking outside the realm of biology. That is, evolutionary theory is strictly the preserve of describing biological change, and is less useful as a generalisable concept. A relatively recent group of papers, however, have taken the conceptual machinery of evolutionary theory (see Hull, 2001) and applied it to language.

It's all natyural, yo!

Broadly speaking, these utterance selection models highlight that language change occurs across two steps, each corresponding to an evolutionary process: (1) the production of an utterance, and (2) the propagation of linguistic variants within a speech community. The first of these, the production of an utterance, takes place across an extremely short timescale: we will replicate particular sounds, words, and constructions millions of times across our production lifetime. It is as this step where variation is generated: phonetic variation, for instance, is not only generated through different speakers having different phonetic values for a single phoneme — the same speaker will produce different phonetic values for a single phoneme based on the context. Through variation comes the possibility of selection within a speech community. This leads us to our second timescale, which sees the selection and propagation of these variants — a process that may “take many generations of the replication of the word, which may–or may not–extend beyond the lifetime of an individual speaker.” (Croft, in press).

Recent mathematical work in this area has highlighted four selection mechanisms: replicator selection, neutral evolution, neutral interactor selection, and weighted interactor selection. I’ll now provide a brief overview of each of these mechanisms in relation to language change.

Continue reading “From Natyural to Nacheruhl: Utterance Selection and Language Change”

Two new Greenhill Papers

Simon Greenhill has just announced two new papers on applying phylogenetic techniques to the study of culture. No doubt I’ll be blogging about these at some point in the future. Below are the abstracts:

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Language evolution in the laboratory

When talking about language evolution there’s always a resistance from people exclaiming;  ‘but how do we know?’, ‘surely all of this is conjecture!’ and, because of this, ‘what’s the point?’

Thomas Scott-Phillips and Simon Kirby have written a new article (in press) in ‘Trends in Cognitive Science’ which addresses some of the techniques currently used to address language evolution using experiments in the laboratory.

The Problem of language evolution

The problem of language evolution is one which encompasses not only the need to explain biologically how language came about but also how language came to be how it is today through processes of cultural evolution. Because of this potential ambiguity arises when using the term ‘language evolution’. To sort this ambiguity the authors put forward the following:

Language evolution researchers are interested in the processes that led to a qualitative change from a non-linguistic state to a linguistic one. In other words, language evolution is concerned with the emergence of language

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Some Links #12: What if there had never been a cognitive revolution?

What if there had never been a cognitive revolution? Apparently, nothing would really be all that different according to Nicolas Baumard over at ICCI. It’s all speculative, in a similar vein to alternative history fiction (I recommend: Making History by Stephen Fry and Difference Engine by William Gibson and Bruce Sterling), with Baumard stating:

My point here is that these key ideas would have emerged even without a Cognitive Revolution. Take for instance the idea that the mind cannot be a blank slate. This idea is totally natural to evolutionary biologists. What about the mind as “a complex system composed of many interacting parts”? Without going back to La Mettrie, Hutcheson or Descartes, one can argue that the idea of modularity is at the core of the research program of neuropsychology since its beginning (the same is true, albeit at a lesser degree, for evolutionary biology). We should not forget as well that, with or without the Cognitive Revolution, brain imaging techniques would have emerged and would have joined neuropsychology and evolutionary biology in decomposing the mind. Add the methodological advances of developmental psychology or social psychology – which were not part of the Cognitive revolution – and you get a pretty big part of today’s ‘Cognition and Culture’.

‘Mad Men -ese. Ben Zimmer has a cool article on Mad Men (easily one of the best shows to have emerged in recent years) and its dedication to accurately portraying 1960s dialogue. But with such dedication comes equally dedicated, and pedantic, criticisms of some of the lines used. For example, Zimmer points to Don’s line “The window for this apology is closing” as being tied to the 70s use of window in a metaphorical sense. On another note: the new season of Mad Men begins tomorrow (25th June) in America.

A growing isolated brain can organize itself. Deric Bownds points to an article by Zhou et al (2010) which disconnected a mouse’s neocortex from the rest of its brain to see how the surface map developed. The results:

During these weeks, the mutant mice, despite having disconnected brains, display a variety of behaviors: eating, drinking, walking, and swimming. Thus, “protomap” formation, namely cortical lamination and formation of areas, proceed normally in absence of extrinsic connections, but survival of projection neurons and acquisition of mature morphological and some electrophysiological features depend on the establishment of normal cortical–subcortical relationships.

Things I’d like to see: a nice, simple, colourful website on evidence-based social policy. Being an avid reader of Ben Goldacre’s Bad Science column, and having read his book of the same name, I was surprised to find that he has another blog. Anyway, the linked post is fairly self-explanatory: he’s calling for someone to create a website looking at evidence-based social policy (something he’s been discussing since at least 2007). I’m a big fan of this idea, which would see social policy based on less rhetorical wrangling and more on actual evidence:

There are three key stages in evidence-based practise: you generate evidence; you collate and appraise it, and then you disseminate and implement. It feels to me like the last bit is currently underdone, and often it takes one clear information hub, or an organisation devoted to promoting something, to move things on.

Why money makes you unhappy. Money is apparently not very good at making us happy. Jonah Lehrer writes about a study exploring the experience-stretching hypothesis, and how it relates to money and happiness. Basically, the argument is that because money allows us to enjoy the best things in life, we actually end up lessening our ability to enjoy the mundane aspects of our life. As the mundane aspects are most frequent, then this isn’t necessarily a good thing. This comes on the back of another paper claiming that the United States, currently the richest nation on Earth, is slowly getting less satisfied with life.  As the current study states:

Taken together, our findings provide evidence for the provocative notion that having access to the best things in life may actually undermine one’s ability to reap enjoyment from life’s small pleasures. Our research demonstrates that a simple reminder of wealth produces the same deleterious effects as actual wealth on an individual’s ability to savor, suggesting that perceived access to pleasurable experiences may be sufficient to impair everyday savoring. In other words, one need not actually visit the pyramids of Egypt or spend a week at the legendary Banff spas in Canada for one’s savoring ability to be impaired—simply knowing that these peak experiences are readily available may increase one’s tendency to take the small pleasures of daily life for granted.