The Origins of Complex Language: An Inquiry into the Evolutionary Beginnings of Sentences, Syllables, and Truth (review)

One has to admire a book that says: ‘If the truth/reference distinction is merely a by-product of how vocal-tract changes affected syntactic evolution, then philosophers are spared the task of trying to make sense of it’ (230). In the process of making such a bold claim, Carstairs-McCarthy (CM) also introduces the reader to two domains of inquiry that do not often mix well: modern evolutionary and contemporary linguistic theories. For that alone the book is worth the price. On top of it, the author lays down a serious, well-thought-out argument for one aspect of syntactic evolution based on something more subtle and perplexing than adaptations, yet entirely within the logic of evolution: what Charles Darwin himself called a ‘preadaptation’ and Stephen Jay Gould had the good sense to re-term an ‘exaptation’. There is much to disagree with when examining this book; but it is the kind of disagreement that inevitably arises from reading good science.

The logic of evolution is negative. In the author’s words, it ‘does not assert that a genetically conditioned anatomical innovation will occur only if it is adaptive; it asserts rather that the genetic basis for that innovation will maintain itself and perhaps spread within the population only if it is not maladaptive’ (182). Therefore, having a property that does no good or harm cannot have an evolutionary consequence. Here’s the rub: Environments change: what was once irrelevant may further down in an evolutionary line result in a useful trait which serves a new purpose. Darwin was well aware of this sort of reasoning, which he employed for wings and flight—an early wing cannot serve flight, hence must be there for some other reason. CM’s book rests on this important premise.

The author exemplifies a new generation of evolutionary researchers who are cautious enough to realize how complex language is. Instead of the customary last word on ‘the evolution of language’ (as a whole), CM gives us his take on three very concrete questions: (1) How did the enormous vocabulary size of human language arise? (2) How come linguistic structures can be analyzed dually, as meaningful and meaningless symbols? (3) Why do we have noun phrases and sentences instead of just one type of expression? He furthermore suggests—this is the gist of the book—that answers to these apparently disparate questions are interrelated. The first reason why the book is immediately interesting is that none of these are obvious points.

The second reason is that, unlike any other proposal I am aware of, the book discusses evolutionary scenarios alternative to the one that actually took place. Evolution without alternatives is like a dry martini without gin. Any story can be told about how something evolved that could not have evolved otherwise; the problem (thus the need for a scientific explanation) arises when that ‘otherwise’ is viable, though possibly less adaptive in an environment, or equally adaptive but not assumed because of some historical accident, etc. CM builds two such scenarios for languages which do not have, in particular, a sentence/noun-phrase distinction.

The book is worthy, also, and highly informative, because it critically examines most evolutionary theories in the market on the origins of syntax (Ch. 4) and valiantly goes into comparative concerns that relate humans with other species, for which CM does not shy away from talking about anatomy, anthropology, animal behavior, and other topics (Ch. 6). Indeed CM does not shy away from anything, as will be apparent in my critique below: My arguments present points of intellectual disagreement, but I cannot say that the author has been incoherent or has pushed his views beyond acceptable limits. In this too my respect for this book is great, for it is unreasonable to demand that a book be ‘right’; I do expect, however, good theories to be wrong for...