(Copyright © 1999 Piero Scaruffi | Legal restrictions - Termini d'uso )
The American neurophysiologist William Calvin has argued in favor of a
darwinian approach to mental life in previous volumes, notably
How Brains Think and
The Cerebral Code .
This time around Calvin explores the birth of language, but the real protagonist
of the book is the co-author, British linguist Derek Bickerton, whose
revolutionary ideas about the origin and function of language have never been
divulged this clearly. The book is written in the form of
letters exchanged between the two scholars.
According to Chomsky's classical theory, which the authot subscribe to, language is an innate skill: we come pre-wired for language, and simply "tune" that skill to the language that is spoken around us. Language is biology, not culture. This implies that the language skill is a fantastic byproduct of evolution. Syntax must be regarded as any other organ acquired via natural selection. The question is then how such a skill developed, since that skill is not present elsewhere in nature: where did it came from? Language appears to be far too complex a skill to have been acquired via step-by-step refinement of the Darwinian kind, especially since we are not aware of any intermediary steps (eg, species that use a grammar only to some extent).
Human language cannot just be due to the evolution of primitive, emotion-laden "call systems". We still cry, scream, laugh, swear, etc. Language has not fully replaced that system of communication. The primitive system of communication continues to thrive alongside language. Language did not replace it, and probably did not evolve from it. Language is something altogether different.
Two aspects of language set it apart from the primitive call system of most animals: the symbolic and the syntactic aspects. A word stands for something (such as an object, a concept, an action). And words can be combined to mean more than their sum ("I walk home" means more than just the concepts of "I", "walking" and "home"). Bickerton believes that syntax is what makes our species unique: other species can also "symbolize", but none has showed a hint of grammar.
Nicholas Humphrey first advocated that language was born out of the need to socialize. On the contrary, Bickerton believes that Humphrey's "social intelligence" had little to do with the birth of protolanguage. Socialization as a selective pressure would not have been unique to humans, and therefore language would have developed as well in other primates. Syntax, instead, developed only in humans, which means that a selective pressure unique to humans must have caused it. Bickerton travels back to the origins of hominids, to the hostile savannas where hominids were easy targets for predators and had precious little food sources. Other primates had a much easier life inthe forests. The ecology of early hominids created completely different selective pressures than the ones faced by other primates. In his quest for the very first utterances, Bickerton speculates that language was born to label things, then evolved to qualify those labels in the present situation: "leopard footprints" and "danger" somehow need to be combined to yield the meaning "when you see leopard footprints, be careful".
Bickerton shows how this kind of "social calculus", coupled with Baldwin effects, could trigger and successfully lead to the emergence of syntax. Social intelligence was therefore important for the emergence of syntax, even if it was not important for the emergence of protolanguage.
Bickerton points out that the emergence of language requires the ability to model other minds. I am motivated to communicate information only if I can articulate this simple scenario in my mind: I know something that you don't know and I would gain something if you knew it. Otherwise the whole point of language disappears.
Social calculus was probably around for millions of years before language was born. Something else was needed to trigger the transformation of protolanguage to language. Calvin believes that physical developments of the brain sped up the acquisition of language skills. Namely, independent Darwin machines worked in the brain using different "codes", and at some point they started communicating in a more efficient way, as if a common "code" was used across the cortex. This not only fostered language, but also planning and reasoning skills: structure thought in general.
Bickerton's theory is intriguind to say the least. He takes Darwin seriously, and, unlike previous linguists, he starts from the savannas where the early hominids evolved. Therein must lie the answer.
Calvin's attempts at applying his paradigm of the Darwin Machine to the brain's processing of language sound a lot less plausible. He's just guessing, and not providing much evidence. And, throughout the book, one is never completely sure what "a Darwin machine" actually stands for.
As interdisciplinary efforts go, this is not a very exciting one. The two scholars proceed independently and occasionally exchange a few comments on each other's essays.