Lexicon before syntax
A much-discussed question in works on language evolution is the following: Which of the two, syntax or lexicon, was there first? Or did both arise simultaneously? Our work on grammaticalization leads to an unambiguous conclusion: The reconstructions proposed, suggest compellingly that lexical distinctions, in particular the distinction between nouns and verbs, must have been in place before functional categories and syntax appeared in human language—hence, there must have been some kind of lexicon before there was grammar.
This hypothesis is in accordance with what most other authors have argued for on the basis of circumstantial evidence. Thus, Givo̒n (2002a: 130, 2002b: 9) finds a coherent body of suggestive evidence in support of this reconstruction, in particular the following:
(a) Ontogenetically, both hearing and signing children acquire the lexicon first, using pre-grammatical communication before acquiring grammar.
(b) Natural second language acquisition often stops short of grammaticalization.
(c) Birds, dogs, horses, primates, and other pre-human species can easily be taught auditory, visual, or gestural lexical code-labels for nouns, verbs and adjectives.
The relative ease with which the teaching of a well-coded lexicon takes place in many pre-human species strongly suggests, according to Givo̒n, that the underlying neuro-cognitive structure is already in place.
Additional evidence for the lexicon-before-grammar hypothesis is provided by Comrie (2000, 2002). After reviewing a wide range of situations where new forms of linguistic communication came into being, using evidence from the analysis of feral children, creoles, deaf sign languages, and twin languages, Comrie suggests:
In the few cases where we can be reasonably certain that a normal child has been exposed to no input, language has not developed.... If a lexicon is provided, then it seems that, at least in the presence of a community of potential speakers, language will develop, and will develop rapidly.... Thus, perhaps somewhat surprisingly, the main task in creating language seems to be providing the lexicon. (Comrie 2000: 1000)
There are in fact some kinds of modern linguistic communication systems, such as pidgins, second-language varieties of the Basic-Variety type, or homesigns that rely overwhelmingly or exclusively on lexical items, while we are not aware of any types of linguistic systems that consist largely or entirely of functional categories only. And if there are non-lexical categories then they normally arise later than the lexicon (e.g. Morford 2002). Note further that in ‘‘fully-fledged’’ modern languages it is at least theoretically possible to make oneself understood by using lexical items only, while a propositional message containing grammar only without a referential lexicon would be contentless (Givo̒n 2002b: 31). Jackendoff and Pinker (2005: 5) therefore bluntly observe that ‘‘it would make little sense for syntax to evolve before words, since there would be nothing for it to combine into utterances.’’
To conclude, we take it to be fairly uncontroversial that the lexicon preceded syntax in language genesis. But there is one caveat:1 At layer II, but perhaps already at layer I, it was possible to combine units—hence, there may have been some elementary syntax, that is to say some form of grammaticalization of the linear concatenation of information flow.
There are further questions that one might wish to raise, such as the following: What exactly was the nature of the lexicon in early language? An answer to this question is essentially not within the scope of our method ology; still, it seems possible to narrow down the range of concepts that might have been lexically distinguished. The main driving force underlying grammaticalization is a strategy according to which existing means of expression are recruited to express novel meanings and grammatical functions. In this way, expressions for concrete, physically perceptual contents are employed for less concrete and perceptually less easily accessible contents (see Heine, Claudi, and Hünnemeyer 1991). We hypothesize that the same strategy was operative in the development of the early lexicon—in the words of Givo ´n (2002b: 28), ‘‘the early human lexicon must have been equally concrete, confining itself to, primarily, sensory-motor spatial-visual objects, states and actions.’’ In support of this hypothesis, Givo̒n relies, first, on what we know about the conceptual capacity and lexical learning of non-human primates, second, on early child vocabulary, and, third, on the fact that ‘‘even in the lexicon of extant human languages, the bulk of abstract vocabulary is derived by analogy and metaphoric extension from concrete core vocabulary’’ (Givo ´n 2002b: 28).
Another question is whether there was any significant correlation between the expansion of the lexicon and that of functional categories— considering the claim made by Li (2002: 90) that an important landmark in the evolutionary process leading toward the crystallization of language was reached when the size of the lexicon attained a critical mass of a few hundred items. Linguistic communications systems that have a small lexical inventory, such as pidgins and other restricted linguistic systems, also tend to dispose of only a limited range of functional categories, suggesting that there is some correlation between the expansion of both lexicon and functional categories. Nevertheless, an answer to this question, or an assessment of Li’s claim, is essentially beyond the scope of our methodology, and we tend to side with Jackendoff (2002: 242), who maintains that the capacity for an open vocabulary is independent of that for grammatical elaboration.
1 We are grateful to an anonymous referee for having drawn our attention to this issue.
