In a letter to William Graham in 1881, Charles Darwin — a year before he died — expressed a grave misgiving about his theory:

But then with me the horrid doubt always arises whether the convictions of man’s mind, which has been developed from the mind of the lower animals, are of any value or at all trustworthy. Would any one trust in the convictions of a monkey’s mind, if there are any convictions in such a mind?

Conviction: it’s a word implying semantics. The dictionary defines conviction as “the act of moving a person by argument or evidence to belief, agreement, consent, or a course of action; the act of convincing” or “the state of being convinced.” These presuppose a conceptual realm, for which language is a tool for communication of abstract ideas that may or may not relate to tangible things.

Can animal minds hold convictions? A materialist might be tempted to think so: a bird might have a conviction it can fly through a window. A cat might have a conviction it can leap from a fence to a table. A monkey might be convinced it can fight off a rival. The “course of action” the animal takes will be confirmed or disconfirmed by evidence. None of us, though, would attempt to reason with the bird, cat, or monkey, using logical argument and appeals to evidence. That requires language.

The “evolution of language” remains a severe challenge to materialist conceptions. Not only must the materialist presuppose that thoughts can supervene on physical neurons, he or she must also attempt to account for a plausible account of the progression of semiotics (the study of meaning-making) from nonlife to animal communication, then from animal communication to human language with its rich vocabulary and capacity for abstract thought.

A valiant effort was made recently by linguist Noam Chomsky, paleoanthropologist Ian Tattersall, cognitive neurobiologist Johan J. Bolhuis, and brain scientist Robert Berwick in PLoS Biology. In the end, however, their effort goes to show how difficult the job is when intelligent causes have been ruled out of bounds a priori.

The evolution of the faculty of language largely remains an enigma. In this essay, we ask why. Language’s evolutionary analysis is complicated because it has no equivalent in any nonhuman species. There is also no consensus regarding the essential nature of the language “phenotype.” According to the “Strong Minimalist Thesis,” the key distinguishing feature of language (and what evolutionary theory must explain) is hierarchical syntactic structure. The faculty of language is likely to have emerged quite recently in evolutionary terms, some 70,000-100,000 years ago, and does not seem to have undergone modification since then, though individual languages do of course change over time, operating within this basic framework.

Language’s “recent” origin has made all the difference:

Our species was born in a technologically archaic context, and significantly, the tempo of change only began picking up after the point at which symbolic objects appeared. Evidently, a new potential for symbolic thought was born with our anatomically distinctive species, but it was only expressed after a necessary cultural stimulus had exerted itself. This stimulus was most plausibly the appearance of language in members of a species that demonstrably already possessed the peripheral vocal apparatus required to externalize it. Then, within a remarkably short space of time, art was invented, cities were born, and people had reached the moon. By this reckoning, the language faculty is an extremely recent acquisition in our lineage, and it was acquired not in the context of slow, gradual modification of preexisting systems under natural selection but in a single, rapid, emergent event that built upon those prior systems but was not predicted by them…. For reasons like these, the relatively sudden origin of language poses difficulties that may be called “Darwin’s problem.” (Emphasis added.)

In order to solve “Darwin’s problem,” they looked for some new thing, some new trait beyond mere “animal communication” (which is widespread in the living world), that would allow language to develop and proliferate. It’s not that hierarchical syntax couldn’t have originated in some other species by natural selection, they speculate, but they know it never did. It’s even absent in the great apes. So in “comparative linguistics” between animals and man, they know there’s “not much to compare.”

What could be responsible for this sudden burst of cultural and mental activity? Assuming that the physical capacity for speech was already in place, they offer a new suggestion: the “merge” operation:

In this view, human language syntax can be characterized via a single operation that takes exactly two (syntactic) elements a and b and puts them together to form the set {a, b}. We call this basic operation “merge”. The “Strong Minimalist Thesis” (SMT) holds that merge along with a general cognitive requirement for computationally minimal or efficient search suffices to account for much of human language syntax. The SMT also requires two mappings: one to an internal conceptual interface for thought and a second to a sensory-motor interface that externalizes language as speech, sign, or other modality. The basic operation itself is simple. Given merge, two items such as the and apples are assembled as the set {the, apples}. Crucially, merge can apply to the results of its own output so that a further application of merge to ate and {the, apples} yields the set {ate, {the, apples}}, in this way deriving the full range of characteristic hierarchical structure that distinguishes human language from all other known nonhuman cognitive systems.

This presupposes a lot and omits much. It’s not clear why parrots or chimpanzees could not come up with the “merge” operator, if it is that simple. And it presupposes (1) computationally or efficient search, (2) an internal conceptual interface for thought, and (3) a sensory-motor interface that externalizes language in speech or hand signals. This is a case of “assume a can opener.” Assuming those leaps and bounds were already made somehow (how did those arrive by mutation and selection?), they have made Darwin’s problem much simpler. They know they have glossed over a lot by assuming “possibly preexisting perceptual and motor mechanisms” before speculating on the magic bullet that gave rise to hierarchical syntax.

Interestingly, one of their references in the preceding quote is to a 2009 article in Nature by Bolhuis and Wynne, “Can Evolution Explain How Minds Work?” In fact, they refer to that article six times. It’s worth re-reading. David Klinghoffer referred to it when it first appeared. Michael Flannery pointed out that same article in three of his posts for ENV in 2011 to support his recounting of Alfred Russel Wallace’s views on intelligent design in the human mind, to show that nothing has changed since Wallace contended that human language was a bridge too far for natural selection.

The Nature of Evolution

One interesting paragraph in their paper is called “The Nature of Evolution.” Here, the authors undermine the explanatory power of Darwin’s greatest idea, natural selection:

Questions of evolution or function are fundamentally different from those relating to mechanism, so evolution can never “explain” mechanisms. For a start, the evolution of a particular trait may have proceeded in different ways, such as via common descent, convergence, or exaptation, and it is not easy to establish which of these possibilities (or combination of them) is relevant. More importantly, evolution by natural selection is not a causal factor of either cognitive or neural mechanisms. Natural selection can be seen as one causal factor for the historical process of evolutionary change, but that is merely stating the essence of the theory of evolution.

Wait a minute — wasn’t natural selection supposed to be a “mechanism” of evolution that made Darwin famous? Here, they have just undermined it as a mechanism or as an explainer! They add, “In addition, evolutionary analysis of language is often plagued by popular, na�ve, or antiquated conceptions of how evolution proceeds.” Agreed.

From there, they leap to speculation that might be described as a punctuated equilibrium model for the origin of language: “evolution is often seen as necessarily a slow, incremental process that unfolds gradually over the eons,” they say; “Such a view of evolutionary change is not consistent with current evidence and our current understanding, in which evolutionary change can be swift, operating within just a few generations…” Conveniently, this allows them to sneak in the “merge” operator in a hidden moment when some caveman found a new way to join two thoughts; the rest is history.

Their entire attempt to evolve language amounts to this: assuming what they need to prove, and leaping in the dark. They presuppose all the hardware and software, then stuff a “merge” operation in at some moment that seems almost magical. “Although this thesis is far from being established and contains many open questions, it offers an account that is compatible with the known empirical evolutionary evidence,” they boast. It’s a story, in other words; a narrative gloss after the fact.

You decide if Chomsky, Berwick, and Tattersall have helped Bolhuis make progress beyond his 2009 worries with Clive Wynne:

Clearly, functional and evolutionary questions are intertwined, as are questions of causation and development. It is unclear, however, what an analysis of the evolutionary history of cognitive behaviours could add to our understanding of how they work, even if such an analysis were possible….

As long as researchers focus on identifying human-like behaviour in other animals, the job of classifying the cognition of different species will be forever tied up in thickets of arbitrary nomenclature that will not advance our understanding of the mechanisms of cognition. For comparative psychology to progress, we must study animal and human minds empirically, without naive evolutionary presuppositions.

The power of intelligent design theory will become clearer when William Dembski’s new book hits the shelves. In Being as Communion, Dembski will make the case that “information” is a fundamental entity of the universe, preceding matter. That is bound to elucidate not only the origin of human language, but of animal communication as well.

Image source: Valerie/Flickr.