Adam's Tongue: How Humans Made Language, How Language Made Humans

by Bickerton, Derek

  So let me, here and now, dissociate myself from vulgar anti-Chomskyanism. To the contrary, while he’s wearing his syntactician’s hat I have nothing but respect and admiration for Chomsky. He’s a better syntactician than I am. He did the behavioral sciences the greatest service ever when he trounced B. F. Skinner and Skinner’s behaviorism. As a result of his initiatives we’ve learned things about language that couldn’t even have been dreamed of a half century ago. Were it not for Chomsky, I could never have launched, or even conceived, my language bioprogram hypothesis (see my book Bastard Tongues if you don’t know what that was). Linguistics is far better off from having had Chomsky than it would have been if he’d never existed.

  I haven’t been entirely uncritical over the years, but my position on most issues hasn’t differed that much from his, and our names have even been coupled from time to time as twin demons of innatism (whatever that is), usually by people in opposite camps who didn’t know too much about us, but at least once by the person who would later, rather surprisingly, become Chomsky’s collaborator in evolutionary studies: Marc Hauser of Harvard.

  So the only reason I’m going up against Chomsky now is that I’m convinced that on the subject of how language evolved, if on nothing else, he’s completely wrong.

  But first, we need some backstory to see where he’s coming from.

  THE STRANGE HISTORY OF AN IMPROBABLE COLLABORATION

  For many years, Chomsky had nothing to say about the evolution of language, except that there was nothing sensible that anyone could say about it. Indeed, he went to some lengths to avoid even discussing the topic, and what little he said seemed aimed at discouraging anyone else from doing so. At a conference in 1975, when asked how language got to be the way it was, he replied, verbatim:

  “Well, it seems to me that would be like asking the question, how does the heart get that way? I mean, we don’t learn to have arms, we don’t learn to have arms rather than wings. What is interesting to me is that the question should be asked. It seems to be a natural question; everyone asks it. And I think we should ask why people ask it.”

  “Why do you ask that question?” was of course one of the stalling tactics in the notorious ELIZA program that, way back in the sixties, MIT computer scientist Joseph Weizenbaum devised to parody a therapeutic session. (If you’d mentioned your father in the answer, the virtual shrink would have continued, “What else comes to your mind when you think of your father?”)

  Many people besides the original questioner wondered why someone who saw language as part of human biology should show not the slightest interest in the biological history of language.

  Then out of a clear blue sky came the 2002 paper by Marc Hauser, Noam Chomsky, and Tecumseh Fitch that, as mentioned in chapter 7, appeared in the “Science’s Compass” section of the prestigious journal Science. As its placement in that particular section suggests, this paper—portentously titled “The Faculty of Language: What Is It, Who Has It, and How Did It Evolve?”—set out with the avowed object of guiding students of language evolution away from sterile and unproductive bickering and into more constructive ways of thinking about the topic.

  The paper caused a stir, not least because of the previous histories of two of its coauthors. Indeed, the surprise of seeing Hauser and Chomsky on the same page was almost as great as what you’d experience if, on opening a back issue of some political journal, you found a position paper on the Middle East coauthored by Yasser Arafat and Ariel Sharon. For until then Hauser and Chomsky had been on opposite sides of at least two of the most crucial issues that language evolution involved.

  One was whether or not language developed out of a prior ACS.

  As a biologist, Hauser subscribed unquestioningly to the “modern synthesis” of neo-Darwinism, which saw evolution as resulting mainly, if not solely, from the selection and recombination of genetic diversity. Every trait had, therefore, to have immediate and direct precursors of some kind, and “language, as good a trait as any, would therefore be viewed as a communicative form that evolved from earlier forms.”

  Chomsky, however, has frequently and vehemently dissociated himself from this view, claiming that “it is almost universally taken for granted that there exists a problem of explaining the ‘evolution’ of human language from systems of animal communication.” However, studies of animal communication only serve to indicate “the extent to which human language appears to be a unique phenomenon, without significant analogue in the animal world.” He concluded that “it is quite senseless to raise the problem of explaining the evolution of human language from more primitive systems of communication.”

  The second issue is the role played by natural selection in language evolution.

  Hauser regarded natural selection as the principal driving force in evolution generally and language evolution in particular. Writing of Steven Pinker’s model of language evolution by gradual increments, each of which was specifically selected for, he described the model as “powerful and lucid,” one that “fits beautifully with the conceptual goals of [Hauser’s] book”—referring to his The Evolution of Communication. He concluded that “natural selection is the only mechanism that can account for the complex design features of a trait such as language.”

  Chomsky, on the other hand, repeatedly argued against any role for natural selection in language evolution. Discussing various attributes of language, he claimed that “to attribute this development to ‘natural selection’ . . . amounts to nothing more than a belief that there is some naturalistic explanation for these phenomena . . . it is not easy even to imagine a course of selection that might have given rise to them.”

  So what brought these unlikeliest of coreligionaries together? In late March 2002, the Fourth International Conference on Language Evolution was held at Harvard, and Hauser and Chomsky appeared together (with Michael Studdert-Kennedy of Haskins Laboratories, an authority on speech sounds) in a two-hour three-handed roundtable discussion. Obviously there’s no point in a roundtable discussion where everyone agrees, so I can only suppose the participants were chosen precisely because they still represented very different approaches to the problem. I was down to present a paper at that conference, but couldn’t attend, so I can’t tell you what magical chemistry clicked into place. But it must have been powerful stuff, since the contradictions were resolved, the joint paper was written, the publication process was completed, and the finished product showed up in the pages of Science, all in less time than it takes to make a baby.

  If you weren’t familiar with their previous writings, you’d never have dreamed its authors had ever been on opposite sides of anything.

  Now, I’ve nothing against authors changing their minds. In fact, they’d better change them, from time to time; otherwise they must be doing faith-based science. I’ve changed my mind several times, but each time I’ve admitted it and explained why I changed. I think that anyone who makes a substantive change of position owes it to colleagues and readers alike to make full disclosure, explaining why the old position was wrong and what new facts, arguments, or discoveries led to the change. Certainly no one has the moral right to practice a cover-up, to behave as if they’d always believed the things they believe now. But the Science paper, far from being a modest and collegial explanation of its authors’ thought processes, adopted a tone that was condescending and didactic, almost hectoring.

  For all its air of entitlement, the paper represented a compromise. In a compromise, you have to give in order to get. What did each of our two authors give and what did they get?

  The key move that made the compromise possible was to partition the territory of language. Language was now officially divided into two parts: FLB, the faculty of language (broad sense), and FLN, the faculty of language (narrow sense), which formed a part of FLB. FLB was everything in language except the “internal computation system”—whatever drives syntax—and that, at least as a first approximation, was simply recursion (the capacity to embed one linguisti
c structure within another of the same kind—one phrase, clause, or sentence inside another). FLN was the only part of FLB that was both (a) limited to humans and (b) specifically dedicated to language. The rest of FLB either had antecedents in other species or, if developed by humans, was initially developed for purposes other than purely linguistic ones.

  Now that language had been split in this way, a deal was possible that gave each author at least some of what he wanted.

  Hauser was able to maintain his belief in natural selection by locating all (or almost all) the components of language in other species, where they might indeed have been selected for, but where naturally they couldn’t have been selected for as language components. As long as he no longer claimed that language per se had been selected for, that was okay with Chomsky. Hauser was even offered the tempting bait that perhaps even recursion, Chomsky’s syntactic holy-of-holies, had non-human origins too. For Chomsky was willing to accept the possibility that recursion had originally developed in some nonhuman species for some purpose that had nothing to do with language (navigation, numbering, and social relationships were three possibilities that were floated).

  Chomsky stopped insisting on the uniqueness of language as a whole, and the degree to which it was separate from the capacities of other species. In return he received confirmation of the special status of recursion as the central mechanism in syntax, and syntax was, of course, what he had always regarded as the most essential component of language. Moreover, if recursion in language could be shown to have come from recursion that had developed in a different species for a different purpose, he could continue to assert that it hadn’t been selected for as a specific linguistic mechanism, which was what he’d been saying all along. He could therefore continue to claim that language hadn’t been selected for qua language; it was just that a whole lot of things selected for other purposes had somehow conspired to produce language.

  Unfortunately, as so often happens with compromises, a great deal had to be swept under the rug.

  THE HAUSER-CHOMSKY-FITCH PROPOSAL

  Perhaps the most surprising thing that went under the rug was human evolution.

  Nothing else tells you so clearly how far the Hauser-Chomsky-Fitch position is from the position of this book. The position of this book is that the evolution of language forms part of the evolution of the human species, and that to think of one without the other is like Hamlet without the prince of Denmark, or Hamlet’s speeches without a word from the king, the queen, the ghost, Ophelia, Polonius, Laertes, or the gravedigger. They’re great speeches, but the play’s the thing. Yet the paper contained not a single mention of human evolution. None of our ancestral species was referred to, not even by bet-hedging designations like “prehuman” or “protohuman” that the current uncertain state of paleoanthropology has obliged me sometimes to use. No times or locations were specified or even tentatively suggested. I’ve complained about linguists who write as if what was evolving was language X in species Y on planet Z at time T, but two of the authors here were biologists.

  If it came to that, there was surprisingly little about Evolution with a big E. Instead, the approach had much in common with that of Charles Hockett, doyen of linguists in his day (and incidentally a target of scorn for Chomskyites as far as his purely linguistic theories were concerned), who in 1960 broke language down into thirteen properties, all but one or two of which, he claimed, could be found in other species (Hauser had written favorably about Hockett’s work in The Evolution of Communication). The main difference was that while Hockett was concerned with properties of language—arbitrariness, semanticity (the conveyance of specific meaning), cultural transmission, and the like—Hauser, Chomsky, and Fitch were concerned with mechanisms for language (or at any rate, mechanisms you could plausibly argue were used in language)—ability to discriminate speech sounds, to operate simple rule systems, to acquire conceptual representations, to imitate vocally, and so on. That at least was an improvement. But both treated language as if it were a grocery list—order all these fine products, put them together, and you’ve got language.

  Basic to both the Hockett and Hauser-Chomsky-Fitch approaches was the same crucial assumption: that the properties or mechanisms they specified amounted to the building blocks of language, from the assembly of which language was actually built. This was a dubious assumption in at least some cases; language evolutionists were being urged to go study things like vocal tract length in birds and primates, even though birds are very distantly related to us and primates are notoriously unable to produce speech sounds. But what’s really wrong here is not the ingredients of the list; it’s the list approach itself.

  Let’s suppose something I think is quite far from the truth, that some prehuman species happened to have collected the full deck—all the precursors, each stepping-stone, every last one of the Hauser-Chomsky-Fitch potentially linguistic mechanisms. And then what? How did all those mechanisms, some of which had never been used for communication, all come together? What made them come together? Since all these mechanisms also did other stuff, why didn’t our prehumans just go on doing that other stuff, living their lives like all other species, never developing language at all?

  So, even given a miraculous creature that had somehow managed to amass the full set of precursors, the authors have failed to answer the most crucial question in their title, “. . . and how did [language] evolve?” But it’s highly unlikely that such a creature ever existed, because many of the mechanisms appealed to are found in animals that aren’t even ancestral to humans. For instance, cotton-top tamarin monkeys have been shown to discriminate speech sounds as accurately as human infants. But chimpanzee hearing is believed to be rather poor; it’s actually been suggested that, even if they could produce speech sounds, their inability to distinguish those sounds would have prevented them from acquiring spoken language. So at least some of these precursors couldn’t form part of our genetic heritage—all that’s been shown is that, given an environmental need, species are capable of developing them.

  What I’m proposing here is a species that started with only some of the prerequisites for language, and developed the rest as it went along constructing the language niche.

  Why do so many people seem to find it so hard to grapple with this concept? I think a lot of it’s due to a misunderstanding of how genes work. There’s a widespread belief that genes are immutable and the instructions they contain constitute nonnegotiable demands. When I proposed that a biological program for language was what caused the similarities among creole languages, people seriously thought that by finding a couple of creoles that didn’t contain the predicted features, they had irrefutably disproved my proposal. The plasticity of the genome is one of the most underappreciated facts in science. To begin to grasp it, just think of this: we have only about twice as many genes as fruit flies, and at least 10 percent of our genes are the same as fruit fly genes. What do we have in common, physically or behaviorally, with fruit flies? Next to nothing. The remit of any gene is extremely broad and vague, executable in a wide variety of ways. So the way any genome expresses itself is only partly a function of its individual genes; it’s partly due to the context—what other genes each gene has to interact with—and partly due to the demands of the particular niche that the gene’s owner happens to be occupying, or constructing. All you can say for certain is that the genes we share with fruit flies must be doing rather different jobs in them and us.

  HAUSER AND ME

  Given the gift of “Science’s Compass” to point the way to benighted language evolutionists, what could have made Hauser and his colleagues choose to point it in the counterproductive direction that they did? Was it simply the inevitable result of the compromise I described above, or was some other factor at work? Back to some backstory again.

  In 1996, the journal Nature (the British equivalent of Science) asked me to review Hauser’s The Evolution of Communication. After the review appeared, Marc wrote me an amicable if somew
hat reproachful letter in which he wondered why I had spent nearly half of the review talking about language. My reply was twofold. First, I pointed out that if the review editor of Nature had asked me to review the book, rather than some specialist in animal communication, or at least a professional biologist, it could only be because that editor saw the language connection as a crucial part of the book. Second, the probable reason why he had chosen a linguist rather than a biologist was that the book, for a general survey of animal communication from an evolutionary perspective, paid an inordinate amount of attention to language.

  Human language does, of course, nominally constitute a form of animal communication, albeit at best a very lonely outlier in that class. There was, then, room in a book of its type for maybe a brief chapter summarizing some of the major respects in which language differed from other members of that class. But you wouldn’t expect to find—nor would even I, a linguist, ever have dreamed of writing—a book on animal communication that, after the briefest of introductions, plunged into forty pages that dealt analytically and critically with what five linguists and two biologists had to say about the evolution of language, that later devoted twenty-eight pages to a discussion of how human language worked, and that sprinkled its text throughout with comparisons between language and other animal systems, finally closing with another dozen pages on how you might design a novel communicative system that would have at least some of the properties of language.

  I’m pretty sure Hauser never intended to suggest that animal communication constitutes some kind of pyramid (or ladder) up which all the animals, in their dumb, stumbling fashion, are trying to climb in order to reach the summit, language. Yet that’s what an account like this inevitably brings to mind. And if you’re wondering why he gave such an account, as I was, maybe the clue lies in this passage: