Spoken language and sign language
'Language' has been defined in three ways: by listing its 'design features'; its structural properties, particularly its 'rule-governed creativity'; and its uses or functions.
In terms of design features, spoken and signed languages differ trivially in terms of the latter's not using the vocal-auditory channel; but have been claimed to differ more significantly in the extent to which spoken language is composed of arbitrary signs, while sign languages are based on more iconic signs. This has led to an erroneous demotion of the status of sign languages. A more careful analysis shows that both types of language are comparable on this dimension in their contemporary forms, although there is some evidence that languages of both media have become more arbitrary over time. Similarly, structural analyses of both systems reveal they show a similar degree of 'duality of patterning', both below the structure of the word or sign, and above it at the level of grammar.
Children go through very similar stages in acquiring either system when it is the 'natural' language of their early environment, although at different rates. Initially sign language is learned earlier; but later this advantage diminishes. However, most deaf children learn sign language under unusual conditions, since most (c.90 per cent) do not have native signing parents. Such children are comparable to those 'learning' spoken creoles on the basis of pidgin inputs: features of their signing system are creations of the 'learners' themselves. This provides some support for Chomsky's contention that language acquisition is not heavily dependent on the nature of the linguistic input.
Creoles are languages which have developed out of pidgins into native languages. Structural similarities between spoken creoles and sign languages may reflect language universals. This has been claimed as supporting the existence of an innate language faculty that strongly constrains the properties of individual languages. An alternative argument is that language structure is more constrained by functional demands, structural characteristics resulting as compromises between the need for a usable language to be clear, cognitively processable, 'quick and easy', and expressive. These two theories may well complement each other: the initial stages of language (both developmentally and historically) might be accounted for in terms of what is biologically given, whereas later language may change more in response to its expanding uses [Eds].
A history of the study of language origins and the gestural primacy hypothesis
Gordon W. Hewes
Speculative writings on language origins seem mainly to be confined, until very recently, to the Classical and Judaeo-Christian West. Until the Enlightenment nearly everything that was said about language origins in the West proceeded from the assumption that language began with Adam in the Garden of Eden.
In the eighteenth century a gestural origin for language was proposed by several writers, and some thought that apes might have a capacity for language. Renewed interest in these ideas developed in the mid-twentieth century, with systematic studies of human sign-languages, and then experiments to teach Great Apes visual languages.
The modern argument for gestural primacy in language origins draws on several lines of evidence, including the following. Sound is of questionable suitability as the original basis for language, given the greater creative capacity and open-endedness of higher primate manual and digital operations. Regular tool-using in hominids probably evolved before vocal language, and the human brain's left-lateralization for speech could have been tacked on to a previous specialization for predominantly right-handed gestural language and precise sequences of manual manipulations. In relatively simple contexts gestural communication has the distinct advantage of greater transparency and ease of communication.
It is speculated that with increasing manual preoccupations proto-speech developed out of mouth-gestures patterned after hand gestures and combined with vocalizations. Now the development of more abstract conceptual thinking was possible, given that gestural language suffers from proneness to commit the logical fallacy of misplaced concreteness. More recently the invention and diffusion of phonemicized speech acted as the principal stimulus for what we recognize as the cultural revolution of the Upper Palaeolithic. The basic advantage of a small set of phonemic units lies in their cognitive indexical function, their facilitation of storage and rapid retrieval of information from an increasingly larger mental lexicon [Eds].
Cognitive abilities in a comparative perspective
Andrew Lock and Michael Colombo
Recent studies of non-human animals indicate that cognitive processes mediate many areas of their behaviour. A number of human cognitive systems, and their properties þ for example memorial processes, categorical auditory and visual perception þ appear to have quite deep phylogenetic roots. It is not yet possible, however, to provide a precise evolutionary classification of these systems, for ecological factors play as large a role in the elaboration of an animal's cognitive abilities as does its phylogenetic status. Thus, many 'indices' that have been proposed as differentiating phylogenetic groups in terms of their 'learning abilities' or 'intelligence' have not been substantiated: initially promising proposals have been confounded by animals from 'lower' taxa showing 'unexpected' levels of ability in sensory domains relevant to their ecological niches. A restricted focus on primates, however, does tend to show an improvement in levels of performance from prosimians to Great Apes on tasks such as reversal learning; and it seems likely that these changes are based in differences in the underlying cognitive abilities and strategies these species employ.
The ability to form concepts has been shown for a number of non-human species. Most of these concepts have physical instantiations. Conflicting claims are made regarding the possession of the concepts of 'same' and 'different'. These appear to be absent in pigeons and goldfish; their status in monkeys is subject to dispute; they are quite well elaborated in the Great Apes, especially in chimpanzees, where most of the experimental effort has been focused. In this last-mentioned species, 'same-different' judgements extend into areas of analogy and transitive inference, which are perhaps closer to reasoning abilities than merely conceptual ones.
Observational learning (or imitation) has been divided into the categories of social facilitation, stimulus enhancement, and imitative copying. The last of these is largely confined to the Great Apes; whereas the other two occur across all the primate groups. Imitative copying is less developed in the Great Apes than in humans, and 'teaching' plays little or no role in the transfer of skills. Chimpanzees are capable of adaptive novel responses in a problem-solving context; but these are more possible for them in some situations than in others. Chimpanzees and orang-utans show self-recognition when confronted with a mirror; but all other primates tested tend to react to mirrors socially, as if they were confronting another conspecific.
Monkeys and apes occasionally act as though they recognize that other individuals have beliefs, but even the most compelling naturalistic and experimentally-induced observations can usually be explained in terms of learned behavioural contingencies, without invoking a higher-order 'understanding' of intentionality. What little evidence there is at this time does point towards chimpanzees (and possibly the other Great Apes) having some 'theory of other minds', although its precise nature is not yet clear.
There are some Piagetian-inspired investigations of comparative cognitive abilities. The Great Apes appear to reach sensorimotor Stage 6 in object permanence, spatial concepts, imitation, and the understanding of causality. Piagetian investigations of possible representational intelligence have proved disappointing to date.
Two oversimplified but none the less useful generalizations would characterize monkeys as possessing the ability to form conceptual representations, and apes as able to manipulate representations; and monkeys as more dominated by immediate perceptual experience than apes. In both cases, abilities are often restricted to particular domains of action. The elaboration of cross-modal and cross-situational abilities appears a major factor in the evolution of primate cognitive skills towards those possessed by modern humans.
Animal language and cognition projects
Interpreting the data on the cognitive and linguistic abilities of non-human species needs to be done with care. The results of particular studies need to be understood in the light of (1) the ontogeny of the ability in question and the specific training procedures involved in demonstrating it; (2) the settings within which abilities are observed þ laboratory versus field; (3) a precise description of and the limits of the abilities claimed to have been demonstrated; (4) the number of individual animals that are claimed to show the abilities in question; and (5) possible problems in experimental designs. Given all these constraints, summary statements must be somewhat provisional.
Some of the Great Apes, in some situations, have achieved the use of rudimentary symbols. This ability can be used to support symbolic forms of communication, especially requests, between apes and their human 'carers'. This symbolic communication ability does not show the multiplicity of functions that humans employ. Particularly in the past, the training methods used to establish these abilities did not bear much resemblance to the procedures by which human children develop language skills; more recent methods do (Savage-Rumbaugh et al 1993; Boysen 1993b). There is little evidence that most apes use grammar in their communications, though one bonobo has attained at least a rudimentary grammar. Furthermore, in some highly specific situations, apes, sea-lions (Zalophus californianus), and dolphins (Tursiops truncatus) are able to comprehend the order of lexcical items, and some apes and pigeons can reproduce certain simple series reliably.
The relation between comprehension and the production of symbols in non-human species is unclear, though the two systems appear more independent of each other than in humans. With specific training to do so, highly 'language'-trained chimpanzees (Pan troglodytes) can transfer symbols learned in one mode to the other, and then generalize this ability to new symbols. The bonobo (Pan paniscus) seems able to make such transfers far more readily. Some enhanced quantitative and reasoning abilities can be demonstrated for 'language'-trained apes as compared to apes not so trained. In some cases these findings depend on the performance of one particularly apt ape; and it is not yet clear that it is only 'language' training that is responsible for the differences found: this research should be extended.
The demonstration of symbol use and category formation in non-primate species implies that it is not the unique organization of the primate brain, nor any special property of their social and physical environments alone, that is responsible for the possession of some symbolic ability. Furthermore, since the apes are our contemporaries and not our ancestors, the question remains open as to the evolutionary significance of those abilities for human abilities. It is clear, however, that humans have a far greater facility for acquiring and using symbolic systems than any other species.
Symbols and structures in language acquisition
Carolyn Johnson, Henry Davis, and Marlys Macken
Children learning natural languages need to master a symbol system with both a constituent and a combinatorial structure. There are at present three main schools of theorizing as to how this mastery is accomplished: the 'interactive', which locates language-learning within its context of use; the 'cognitive', which locates language-learning as part of symbolic development in general; and the 'autonomous', which emphasizes the independence of the study of grammatical competence from both language use and general principles of cognitive development. Additionally, the task of language-learning is generally investigated under a number of independent headings: phonological acquisition; lexical acquisition; morphological and syntactic acquisition; and pragmatic acquisition.
The phonological (sound) system of a language is rule-based. Very young human infants can discriminate the majority of the features which comprise the adult sound system, and can do so across complex physical dimensions. At a minimum, infants' abilities provide an initial grid for segmenting, sorting, and classifying phonetic categories, and for mapping these to the higher levels of phonological systems. For production, there is continuity from the babbling period into early language. The early productive sound systems appear to be based on words rather than smaller units, words not being initially analysed into their component phonemes. This analysis begins between the ages of two and four years, although the child's system still remains simplified compared to that of the adult. The process of phonological development follows no invariant sequence, and can show regressions at the same time as the system becomes more complex. Some form of 'cognitive' theory at present provides the best explanatory framework.
Verbal communication is preceded by gestural communication, beginning at about nine months of age. Accounts have been offered in which gestural communication is claimed to be necessary for later language development, and continuous with it; but the evidence on both these points is equivocal. Meaningful 'words' are used from about one year of age. There is a spurt in vocabulary development from around eighteen months. Errors in word use provide the major data source for theories of semantic development. These data have formed the basis of a number of theoretical accounts; but none of these are yet comprehensive in their explanatory powers. Crucially lacking is an account of how the child learns to relate words to concepts, and clear criteria for determining when a child's 'words' are truly symbolic.
The acquisition of syntax can be divided into three stages: presyntactic; syntactic; and postsyntactic. Early presyntactic word-combinations are of three types: the combination of words that reflect grammatically relevant real-world relations; a word plus an intonationally integrated but meaningless extra syllable; and formulaic or rote-learned sequences. It is not clear whether there is any continuity between the combinatorial structures of this stage and those of the next, syntactic, stage, which lasts from about two to five years of age. First-language learners make very few errors in constructing complex grammars þ a fact supporting the claim that there are innate constraints, whether specifically linguistic or not, on a learner's 'hypothesis space'. Analysis of errors in learning suggests that morphological learning may occur via a probabilistic mechanism, whereas syntactic learning may be based on different, possibly innate, principles. The final postsyntactic stage represents the integration of the newly-emerged syntactic system with the real-world knowledge the child has accumulated.
Early functions of language are of three types: solicitation of action, social interaction, and joint attention; expression of affect; and participation in games. With the advent of naming, children can also label and request labels. Later developments, such as threatening, promising, and deceiving, have not been systematically studied.
The best-supported theories of language development are of the 'autonomous' school. It appears that language-learning skills are domain-specific, and there are few parallels with non-linguistic domains, or precursors to the formal systems. Thus, the autonomous view presents difficulties for both onto- and phylogenic accounts, in that it is a discontinuity view. However, the 'interactive' and 'cognitive' schools at present offer less plausible accounts of the acquisition of linguistic abilities than 'autonomous' ones, even though they offer more continuous views of development, and hence might be more attractive to an evolutionary scenario at first sight [Eds].
The reconstruction of the evolution of human spoken language
Mary LeCron Foster
Language is an analogical system for classification on multiple levels. Language systems build upon semantic analogies and analogies in phonological, morphological, and syntactic distributions (positional analogies). New meanings are created through the process of metaphorical extension. The direction of language change is determined in large part by this process and by analogical systematization þ hierarchical congruence of classes.
The regularities of sound-change reconstructed by the comparative method provide the most reliable diagnoses of remote linguistic relations; but these are limited to 'families', or, in a few cases, 'stocks' made up of interrelated families. Broader groupings, 'phyla' or 'super-stocks', are suggested on the basis of typological relations, rather than on firmly established sound-correspondences. The basis for going even further and attempting to reconstruct a single prototype for all the world's spoken languages is not agreed upon; but the reconstruction should reflect systematic correspondences in sound and meaning throughout, whether insights were initially gained from typological studies of phonology and/or from internal reconstructions. Hypotheses must show system. While individual meanings underlying reconstructed forms need not be identical, differences should be minimized. Once correspondences are firmly established, culturally influenced semantic variations are useful in assessing degrees of interrelationship among languages.
Pursuing the monogenetic reconstruction through this bare-bones phonemic approach, refined by a series of simplifications, leads to the startling hypothesis that the sounds of which the VC and CVC roots are composed were originally themselves meaning-bearers. These phememes, as they are termed, were minimal units of sound whose meaning derived from the shaping and movement of the articulatory tract. In other words, the phonemes of language, as well as the combinations into which they unite within the word were originally not arbitrary signs, but abstract, highly motivated analogical symbols.
In the earliest stage of primordial language, single phememes expressed notions o space and motion. Across the evolution of the genus Homo these were differentiated and new phememes created, hypothetically in stages, until the phememic inventory was completed during the Upper Palaeolithic. In the Neolithic period, it is hypothesized, syllabic concatenation with morphophonemic merging increasingly obscured the analogical significance of phememes, which gradually became what we now know as phonemes. Nevertheless, in the roots of most modern languages a number of the primordial phememes are still recognizable [Eds].
Theoretical stages in the prehistory of grammar
This chapter conjectures that the hierarchical structure of present-day grammars might be the result of an evolutionary process. Grammar is taken to be a communicative device patterned to cater for various communicative intentions such as asking questions, making statements, and expressing comments. These intentions are themselves elaborated in the course of an evolving dialogic system. Each communicative intention might be thought of as having a corresponding pattern for its expression. If so, this would lead to a non-integrated grammatical system. Hence the notion of 'recency dominance' is introduced here, whereby a newly-emerged pattern becomes dominant and 'reworks' older patterns into conformity with it. Eight stages of elaboration are proposed. These are probably not discrete; rather, language evolution should be viewed as proceeding in a more mosaic pattern.
The first stage þ necessarily without any prior pattern to build on þ concerns getting is motivated by the seeking of some obligement: termed here 'solicitation'. Granting these obligements constitutes 'compliance'. Finally, a 'close-out' indicates the exchange is finished. This sequence constitutes a 'frame of dialogue' that represents the source of later grammatical functions, which become necessary to handle communicative functions as they become more elaborated þ vocative from address; imperative and interrogative moods of the verb from solicitation; affirmative (and negative) from compliance (and refusal); and various markers for turn-taking. This frame also contributes to the provision of first and second persons of the verb when they are later grammaticalized.
A minor complexification of these abilities yields the next stage, ostension þ pointing at a visible item with one's index finger. Ostension has three important facets: it is for another (and is hence situated in the earlier dialogic frame); it implies the addressee understands what is being pointed at; and it is oriented on the speaker þ that is, it is 'deictic'. Ostension primarily concerns visible items, and distinguishes between those within and beyond reach, but can be extended to indicate non-visible phenomena. In this instance, however, ostension can no longer be contextually supported, but needs a new form, 'identification', which is secured by 'naming'. This builds on ostention, but extends it to constitute a new stage.
Identification can be secured by gestural imitation of shape or activity. Vocal units may have taken the first step towards being words by reformulating some of this gestural inventory, or by iconic representation. The notion of referential symbolism via words may not have been fully perceived at their creation, and they may well have arisen and been worked into the communicative system in an ad hoc manner. One method of securing referential symbolism is 'thematization' and this is proposed as the next stage.
'Thematic roots' are an organisational principle exploited in some language systems whereby a set of phonological alternances around a vowel allow the expression of particular aspects of the notion contained in the root. Verbs and nouns are not distinguished, but are implicit in the particular semantic features expressed by members of a theme. Thematic clusters constitute a semantic route towards grammar, in that their semantic features are sorted out in modern languages into the basic noun/verb distinction and grammaticalized into syntax.
Topic-comment structures are proposed as the first stage in the transition toward syntax. Initial topic-comment structures are asyntactic, since their relations are purely pragmatically based. These motivate the possibility of expressing third-person action, and the realization of this enables a speaker to depict scenes, which itself leads to a forefronting of implicit case relations, and moves topic/comment structures toward the realm of 'narrative' which requires considerable grammatical support for its effective handling. Narrativity begins to shift the relating of events from the intersubjective realm of the dialogic participants towards the objectification of events, yielding an 'epistemic' patterning of discourse, and motivating syntactic devices that handle the hitherto implicit features of narrative. This last, epistemic, stage may be relatively recent, and characteristic of a level of social organisation that produces the state [Eds].
Social and cognitive factors in the historical elaboration of writing
David Barton and Mary Hamilton
Writing originated separately in Mesopotamia and Egypt, China, pre-Columbian America, and, possibly, the Indus Valley. The earliest evidence of writing is cuneiform script from Mesopotamia at c.3500 BC. Six earlier classes of visual representation contributed to the development of writing-systems: the expressive and ritualistic markings found in cave art; tallying devices; property markings and totems; tokens; mnemonic devices; and pictographic/ideographic narrative forms. Early writing-systems were used for political and economic, religious, and historical-literary functions. There is no single order of functional development that applies to all cultures.
Writing-systems are classified into three types: logographic systems, which represent morphemes; syllabic systems, which represent syllables; and alphabetic systems, which represent units more closely related to phonemes than to syllables. Writing-systems tend to develop from the logographic to the syllabic, though this is not always the case. As syllabic systems interact with the structure of the spoken language they are trying to capture they adapt themselves through a variety of devices. This historical elaboration is not well served by considering it to be an evolutionary sequence, as has often been claimed.
Strong claims that literacy per se qualitatively affects cognitive abilities are not well supported by evidence. Literacy is better seen as a communicative technology involved in the production and reproduction of shared meaning or knowledge. It is the social practices sustaining these meanings that determine the consequent skills associated with literacy. Arguments that credit literacy as a prime causal factor underlying social change are thus oversimplistic. Rather, literacy is just one factor in a nexus which includes social and political institutions.
Printing led to a restructuring of literate activities through the incorporation of a technical invention into the social organization and production of knowledge. Printing assists in the cultural diffusion of ideas, and in the standardization of knowledge and linguistic forms. However, social factors again play a role in determining access to literacy, and thus the extent to which printing can act as an agent in the diffusion of literacy [Eds].