Which came first, the word or the sentence? Although the answer may seem obvious, I have been thinking about last week’s post and it occurs to me that the answer to my basic question can help judge the correctness of Chomsky’s theory of generative grammar versus the theory of shared perception favored by this blog.
Children today speak single words first, which might seem to indicate that the word preceded the sentence, but generative theorists have a reply. According to the shared perception theory, when a baby says doggie the word draws attention to the dog. According to generative theory, however, the baby's speech is "holophrastic," expressive of an entire phrase, and can be properly represented as meaning, “There is a dog,” or some such. To date, the choice between the two interpretations has always seemed a matter of taste, but now I wonder.
The issue comes up because of a couple of paragraphs in the article titled , “A Biolinguistic Agenda” by Mark D. Hauser and Thomas Bever in the November 14 Science magazine (abstract here). I discussed the paper last week (see: A Biolinguistic Agenda?) and wasn’t too favorable, but the paper made some theoretically interesting remarks about the division of the brain into distinct right and left halves, or as it is called technically: the lateralization of the brain.
The authors report that lateralization varies from person to person, with the deepest ambiguities involving members of families that include left-handed people. Words can come from either hemisphere of the brain. However,
all subjects [investigated] show left-hemisphere activation for syntactic processes. … The observed variability in how the lexicon is accessed and represented suggests that it is indeed a biologically separable component on linguistic knowledge. [p. 1058]
Their point is the classic Chomskyan one that syntax is an independent element of language that can function without reference to the meaning of the words. The point was made in the famous sentence Colorless, green ideas sleep furiously which is meaningless, but grammatical. Although the sentence is likely to puzzle unsophisticated or uneducated people, the kind of person found at MIT can easily see that it follows a recognizable pattern and that somehow colorless modifies the subject green ideas even while contradicting it.
The observation that syntax is produced by a distinct, specialized region of the brain does not prove Chomsky’s theory but it stiffens the spine of generative thinkers. And it provokes the question I posed, in slightly different form, at the start of this post: which came first, the generally distributed lexicon or the syntactic lateralization?
Different theories point to different answers. The shared-perception theory of language makes sense of the common assumption that words came first, sentences later. Single words (doggie) piloted attention, later groups of words (biggie doggie) focus attention on a detail, and then sentences create full perceptions (biggie doggie chase kitty). So in this view, the syntactic lateralization came after the brain was already using a more generally distributed lexicon.
Generative grammar, especially in its take-no-prisoners, Chomskyan form, points in the opposite direction. We evolved syntactic structure (and, therefore, lateralization) first. It gave us the capacity to think more clearly. Only as syntactic thought spread did speech and words evolve. (See: Chomsky's Theory of Language Origins). So the generally distributed lexicon is more recent.
Today we cannot settle which processes came first. We cannot tell from fossil skulls when lateralization occurred. But that’s today. DNA and fossil evidence may eventually settle the matter. And it is a relief to think that, in principle, the dispute may not have to always turn on matters of taste.