Hence, Chomsky urged the development of generative grammars of this type. Syntactic theory has now gone well beyond this early vision — both phrase structure and transformation rules were abandoned in successive linguistic revolutions wrought by Chomsky and his students and colleagues see Newmeyer , for a history of generative linguistics. But what has not changed — and what is important for our purposes — is that in every version of the grammar of say English, the rules governing the syntactic structure of sentences and phrases are stated in terms of syntactic categories that are highly abstracted from the properties of utterances that are accessible to experience.
As an example of this, consider the notion of a trace. Traces are symbols that appear in phrasemarkers and mark the path of an element as it is moved from one position to another at various stages of a sentence's derivation, as in 1 , where t i markes the NP Jacob 's position at an earlier stage in the derivation. See Chomsky and Lasnik and Uriagereka for more on traces and other empty categories. Traces and other similarly abstract properties of languages thus raise a question for the theory of language acquisition.
As a consequence, children's feat in learning a language appears miraculous: how could a child learn the myriad rules governing linguistic expression given only her exposure to the sentences spoken around her? In response to this question, most 20th century theorists followed Chomsky in holding that language acquisition could not occur unless much of the knowledge eventually attained were innate or inborn. The gap between what speaker-hearers know about language its grammar, among other things and the data they have access to during learning the pld is just too broad to be bridged by any process of learning alone.
Learning a particular language thus becomes the comparatively simple matter of elaborating upon this antecedently possessed knowledge, and hence appears a much more tractable task for young children to attempt. Over the years, two conceptions of the innate contribution to language learning and its elaboration during the learning process have been proposed.
In earlier writings e. He saw this knowledge as being embodied in a suite of innate linguistic abilities, concepts, and constraints on the kinds of grammatical rules learners can propose for testing. By the 's, a less intellectualized conception of how language is acquired began to supplant the hypothesis-testing model. The innate UG was no longer viewed as a set of tools for inference; rather, it was conceived as a highly articulated set of representations of actual grammatical principles. Of course, since not everyone ends up speaking the same language, these innate representations must allow for some variation.
To illustrate how parameter setting works, consider a simplified example discussed in more detail in Chomsky All languages require that sentences have subjects, but whereas some languages like English require that the subject be overt in the utterance, other languages like Spanish allow you to leave the subject out of the sentence when it is written or spoken. Roeper and Williams is the locus classicus for parameter-setting models; Ayoun is more up-to-date; Pinker, ch. These two approaches to language acquisition clearly differ significantly in their conception of the nature of the learning process and the learner's role in it, but we are not concerned to evaluate their respective merits here.
Rather, the important point for our purposes is that they both attribute substantial amounts of innate information about language to the language learner. We will focus on the following question:. Terminological Note: As Chomsky acknowledges e. This ambiguity is important when one is evaluating Chomskyan claims that we have innate knowledge of UG.
On the second reading, however, it is possible that learners have innate knowledge of language without that knowledge's being knowledge of UG as currently described by linguists : learners might know things about language, yet not know Binding Theory, or the Principle of Structure Dependence, etc. The reverse, however, is not the case: there might be reason to think that a speaker knows something about language innately, without its constituting reason to think that what they know is Universal Grammar as described by Chomksyan linguists; Chomksy might be right that we have innate knowledge about language, but wrong about what the content of that knowledge is.
These issues will be clarified, as necessary, below. Since language mastery involves knowledge of grammar, and since grammatical rules are defined over properties of utterances that are not accessible to experience, language learning must be more like theory-building in science. However, argued Chomsky, just as conditioning was too weak a learning strategy to account for children's ability to acquire language, so too is the kind of inductive inference or hypothesis-testing that goes on in science. Successful scientific theory-building requires huge amounts of data, both to suggest plausible-seeming hypotheses and to weed out any false ones.
The first type of inadequacy is, of course, endemic to any kind of empirical inquiry: it is simply the problem of the underdetermination of theories by their evidence. Cowie has argued elsewhere that underdetermination per se cannot be taken to be evidence for nativism: if it were, we would have to be nativists about everything that people learn Cowie ; What of the second kind of impoverishment?
If the evidence about language available to children does not enable them to reject false hypotheses, and if they nonetheless hit on the correct grammar, then language learning could not be a kind of scientific inquiry, which depends in part on being able to find evidence to weed out incorrect theories. And indeed, this is what Chomsky argues: since the pld are not sufficiently rich or varied to enable a learner to arrive at the correct hypothesis about the grammar of the language she is learning, language could not be learned from the pld.
For consider: The fact i that the pld are finite whereas natural languages are infinite shows that children must be generalizing beyond the data when they are learning their language's grammar: they must be proposing rules that cover as-yet unheard utterances. This, however, opens up room for error.
In order to recover from particular sorts of error, children would need access to particular kinds of data. If those data don't exist, as ii asserts, then children would not be able to correct their mistakes. Thus, since children do eventually converge on the correct grammar for their language, they mustn't be making those sorts of errors in the first place: something must be stopping them from making generalizations that they cannot correct on the basis of the pld.
Chomsky e. As Chomsky puts it:. Chomsky rarely states the argument from the poverty of the stimulus in its general form, as Cowie has done here. Instead, he typically presents it via an example. She wants to figure out the rule you use to turn declaratives like 1a and 2a into interrogatives like 1b and 2b. Here are two possibilities:. Both hypotheses are adequate to account for the data the learner has so far encountered.
Nonetheless, H 1 is false, as is evident when you look at examples like 3 :. H 1 generates the ungrammatical question 3b , whereas H 2 generates the correct version, 3c. That we know this is evident, Chomsky argues, from the fact that we all know that 3b is not the right way to say 3c. The question is how we could have learnt this. Suppose, for example, that based on her experience of 1 and 2 , a child were to adopt H 1.
How would she discover her error? There would seem to be two ways to do this. First, she could use H 1 in her own speech, utter a sentence like 3b , and be corrected by her parents or caregivers; second, she could hear a sentence like 3c uttered by a competent speaker, and realize that that sentence is not generated by her hypothesis, H 1. So in answer to the question: how do we learn that H 2 is better than H 1 , Chomsky argued that we don't learn this at all!
A better explanation of how we all know that H 2 is right and H 1 is wrong is that we were born knowing this fact. In sum, we know that H 2 is a better rule than H 1 , but we didn't learn this from our experience of the language. Rather, this fact is a consequence of our inborn knowledge of UG. Chomskyans contest that there are many other cases in which speaker-hearers know grammatical rules, the critical evidence in favor of which is missing from the pld. Pullum and Scholz , discuss two other well known examples.
Nativists thus conclude that numerous other principles of UG are innately known as well. Together, these UG principles place strong constraints on learners' linguistic theorizing, preventing them from making errors for which there are no falsifying data. So endemic is the impoverishment of the pld , according to Chomskyans, that it began to seem as if the entire learning paradigm were inapplicable to language. As more and more and stricter and stricter innate constraints needed to be imposed on the learner's hypothesis space to account for their learning rules in the absence of relevant data, notions like hypothesis generation and testing seemed to have less and less purchase.
Many, probably most theorists in modern linguistics and cognitive science have accepted Chomsky's poverty of the stimulus argument for the innateness of UG. As a result, a commitment to linguistic nativism has underpinned most research into language acquisition over the last odd years. Nonetheless, it is important to understand what criticisms have been leveled against the argument, which I schematize as follows for convenience:. In response, Chomsky e. However, while it is certainly legitimate to propose a special relationship between speakers and grammars, unanswered questions remain about the precise nature of cognizance.
Is it a representational relation, like belief? See the papers collected in MacDonald , for discussion of this last issue; see Devitt for arguments that there is no good reason to suppose that speakers use any representations of grammatical rules in their production and comprehension of language. These issues bear on the argument from the poverty of the stimulus because that argument may appear more or less impressive depending on the answers one gives to them.
If, for instance, one held that grammars are belief-like entities, explicitly represented in our heads in some internal code cf. Stich , then the question of how those beliefs are acquired and justified is indeed a pressing one — as, for different reasons, is the question of how they function in performance see Harman , Or if, to take a third possibility, one were to reject generative syntax altogether and adopt a different conception of what the content of speakers' grammatical knowledge is — along the lines of Tomasello , say — then that again affects how one views the learning process.
In other words, one's ideas about what is learned affect one's conception of what is needed to learn it. In the example of polar interrogatives, discussed above, we saw how children apparently require explicit falsifying evidence in order to rule out the plausible-seeming but false hypothesis, H 1. Premiss 2 of the argument generalizes this claim: there are many instances in which learners need specific kinds of falsifying data to correct their mistakes data that the argument goes on to assert are unavailable.
These claims about the data learners would need in order to learn grammar are underpinned by certain assumptions about the learning algorithm they employ. For example, the idea that false hypotheses are rejected only when they are explicitly falsified in the data suggests that learners are incapable of taking any kind of probabilistic or holistic approach to confirmation and disconfirmation.
Likewise, the idea that learners unequipped with inborn knowledge of UG are very likely indeed to entertain false hypotheses suggests that their method of generating hypotheses is insensitive to background information or past experience. The non-nativist language learner as envisaged by Chomsky in the original version of the poverty of the stimulus argument, in other words, is limited to a kind of Popperian methodology — one that involves the enumeration of all possible grammatical hypotheses, each of which is tested against the data, and each of is rejected just in case it is explicitly falsified.
As much work in philosophy of science over the last half century has indicated, though, nothing much of anything can be learned by this method: the world quite generally fails to supply falsifying evidence. Instead, hypothesis generation must be inductively based, and dis confirmation is a holistic matter.
Thus arise two problems for the Chomskyan argument. First, it is not all that surprising to discover that if language learners employed a method of conjecture and refutation, then language could not be learned from the data. In other words, the poverty of the stimulus argument doesn't tell us much we didn't know already.
Secondly, and as a result, the argument is quite weak: it makes the negative point that language acquisition does not occur via a Popperian learning strategy, but it favors no specific alternative to this acquisition theory. In particular, the argument gives no more support to a nativist UG-based theory than to one that proposed say that learners formulate grammatical hypotheses based on their extraction of statistical information about the pld and that they may reject them for reasons other than outright falsification — because they lack explicit confirmation, or because they do not cohere with other parts of the grammar, for instance.
In reply, some Chomskyans e. It's pointless, they claim, for nativists to try to argue against theories that are mere gleams in the empiricist's eye, particularly when Chomsky's approach has been so fruitful and thus may be supported by a powerful inference to the best explanation. Others have argued explicitly against particular non-nativist theories — Marcus , , for instance, discusses the shortcomings of connectionist accounts of language acquisition. A recent book by Michael Tomasello Tomasello addresses the nativist's demand for an alternative theory directly.
Tomasello argues that language learners acquire knowledge of syntax by using inductive, analogical and statistical learning methods, and by examining a broader range of data for the purposes of confirmation and disconfirmation. Tomasello's theory differs from a Chomskyan approach in three important respects.
First, and taking up a point mentioned in the previous section, it employs a different conception of linguistic competence, the end state of the learning process. Rather than thinking of competent speakers as representing the rules of grammar in the maximally abstract, simple and elegant format devised by generative linguists, Tomasello conceives of them as employing rules at a variety of different levels of abstraction, and, importantly, as employing rules that are not formulated in purely syntactic terms. For generative linguists, the pld comprises a set of sentences, perhaps subject to some preliminary syntactic analysis, and the child learning grammar is thought of as embodying a function which maps that set of sentences onto the generative grammar for her language.
On Tomasello's conception, the pld includes not just a set of sentences, but also facts about how sentences are used by speakers to fulfill their communicative intentions. On his view, semantic and contextual information is also used by children for the purposes of acquiring grammatical knowledge. This gives rise to a third important respect in which Tomasello's theory differs from that of the linguistic nativist. On his view, children learn language without the aid of any inborn linguistic information: what children bring to the language learning task — their innate endowment — is not language-specific.
These skills include: i the ability to share attention with others; ii the ability to discern others' intentions including their communicative intentions ; iii the perceptual ability to segment the speech stream into identifiable units at different levels of abstraction; and iv general reasoning skills, such as the ability to recognize patterns of various sorts in the world, the ability to make analogies between patterns that are similar in certain respects, and the ability to perform certain sorts of statistical analysis of these patterns.
Thus, Tomasello's theory contrasts strongly with the nativist approach. Although assessing Tomasello's theory of language acquisition is beyond the scope of this entry, this much can be said: the oft-repeated charge that empiricists have failed to provide comprehensive, testable alternatives to Chomskyanism is no longer sustainable, and if the what and how of language acquisition are along the lines that Tomasello describes, then the motivation for linguistic nativism largely disappears.
A third problem with the poverty of the stimulus argument is that there has been little systematic attempt to provide empirical evidence supporting its assertions about what the pld contain. This is an old complaint cf. Sampson which has recently been renewed with some vigor by Pullum and Scholz , Scholz and Pullum , and Sampson Pullum and Scholz provide evidence that, contrary to what Chomsky asserts in his discussion of polar interrogatives, children can expect to encounter plenty of data that would alert them to the falsity of H 1. Chomskyans respond in two main ways to findings like this.
First, they argue, it is not enough to show that some children can be expected to hear sentences like Is the girl in the jumping castle Kayley's daughter? All children learn the correct rule, so the claim must be that all children are guaranteed to hear sentences of this form — and this claim is still implausible, data like those just discussed notwithstanding. Sampson ff. He notes that in addition to supporting Chomsky's claims about the poverty of the pld , such data simultaneously problematize his claims about children's knowledge of the auxiliary-fronting rule itself.
Sampson found that speakers invariably made errors when apparently attempting to produce complex auxiliary-fronted questions, and often emended their utterance to a tag form instead e. Hespeculates that the construction is not idiomatic even in adult language, and that speakers learn to form and decode such questions much later in life, after encountering them in written English. If that were the case, then the lack of complex auxiliary fronted questions in the pld would be both unsurprising and unproblematic: young children don't hear the sentences, but nor do they learn the rule.
To my knowledge, children's competence with the auxiliary fronting rule has not been addressed empirically. Secondly, Chomskyans may produce other versions of the poverty of the stimulus argument. For instance, Crain constructs a poverty of the stimulus argument concerning children's acquisition of knowledge of certain constraints on movement. However, while Crain's argument carefully documents children's conformity to the relevant grammatical rules, its nativist conclusion still relies on unsubstantiated intuitions as to the non-occurrence of relevant forms or evidence in the pld.
It is thus inconclusive. Crain ; Crain's experiments and their implications are discussed in Cowie ; Cf. The argument from 1 , 2 , and 3 to 4 appears valid.
Remember Scarborough: a result of the first arms race of the twentieth century
What 4 concludes, however, is that G is unlearnable, period, from the pld — a move that several authors, particularly connectionists, have objected to. See especially Elman et al. Chomskyans typically take this point, conceding that the argument from the poverty of the stimulus is not apodeictic. Nonetheless, they claim, it's a very good argument, and the burden of proof belongs with their critics. After all, nativists have shown the falsity of the only non-nativist acquisition theories that are well-enough worked out to be empirically testable, namely, Skinnerian behaviorism and Popperian conjecture and refutation.
In addition, they have proposed an alternative theory, Chomskyan nativism, which is more than adequate to account for the phenomena. In empirical science, this is all that they can reasonably be required to do. The fact that there might be other possible acquisition algorithms which might account for children's ability to learn language is neither here nor there; nativists are not required to argue against mere possibilities.
In response, some non-nativists have argued that UG-based theories are not in fact good theories of language acquisition. Tomasello ff. Second, there is the problem of developmental change, also emphasized by Sokolov and Snow, It is difficult to see how UG-based approaches can account for the fact that children's linguistic performance seems to emerge piecemeal over time, rather than emerging in adult-like form all at once, as the parameter-setting model suggests it should.
At the very least, such objections serve to equalize the burden of proof: non-nativists certainly have work to do, but so too do nativists. Nativists need to show how their theory can account for the known course of language acquisition. Merely pointing out that there is a possibility that such theories are true, and that they would, if true, explain how language learning occurs in the face of an allegedly impoverished stimulus, is only part of the job.
Because they are defending the view that all of UG is inborn, Chomskyans must be credited with holding that the primary data are impoverished quite generally. That is, if the innateness of UG tout court is to be supported by poverty of the stimulus considerations, the idea must be that the cases that nativists discuss in detail polar interrogatives, complex auxiliaries, etc.
Nativists quite reasonably do not attempt to defend this claim by endless enumeration of cases. Some possible hypotheses must be ruled out a priori. But, critics allege, what does not follow from this is any particular view about the nature of the requisite constraints. Cowie ch. A fortiori, what does not follow from this is the view that Universal Grammar construed as a theory about the structural properties common to all natural languages, per Terminological Note 2 above is inborn.
For all the poverty of the stimulus argument shows, the constraints in question might indeed be language-specific and innate, but with contents quite different from those proposed in current theories of UG. Or, the constraints might be innate, but not language-specific. For instance, as Tomasello argues, children's early linguistic theorizing appears to be constrained by their inborn abilities to share attention with others and to discern others' communicative intentions.
On his view, a child's early linguistic hypotheses are based on the assumption that the person talking to him is attempting to convey information about the thing s that they are both currently attending to. Another alternative is that the constraints might be learned, that is, derived from past experiences. An example again comes from Tomasello He argues that entrenchment , or the frequency with which a linguistic element has been used with a certain communicative function, is an important constraint on the development of children's later syntactic knowledge.
For instance, it has been shown experimentally that the more often a child hears an element used for a particular communicative purpose, the less likely she is to extend that element to new contexts. See Tomasello In short, there are many ways to constrain learners' hypotheses about how their language works. Since the poverty of the stimulus argument merely indicates the need for constraints, it does not speak to the question of what sorts of constraints those might be.
In response to this kind of point, Chomskyans point out that the innateness of UG is an empirical hypothesis supported by a perfectly respectable inference to the best explanation. Of course there is a logical space between the conclusion that something constrains the acquisition mechanism and the Chomskyan view that these constraints are inborn representations of Binding Theory, Theta theory, the ECP, the principle of Greed or Shortest Path and so on. But the mere fact that the argument from the poverty of the stimulus doesn't prove that UG is innately known is hardly reason to complain.
This is science, after all, and demonstrative proofs are neither possible nor required. What the argument from the poverty of the stimulus provides is good reason to think that there are strong constraints on the learning mechanism. UG is at hand to supply a theory of those constraints. Moreover, that theory has been highly productive of research in numerous areas linguistics, psycholinguistics, developmental psychology, second language research, speech pathology etc.
These successes far outstrip anything that non-nativist learning theorists have able to achieve even in their wildest dreams, and support a powerful inference to the best explanation in the Chomskyan's favor. In addition, there is a general debate within the philosophy of science as to the soundness of inferences to the best explanation: does an explanation's being the best available give any additional reason over and above its ability to account for the phenomena within its domain to suppose it true?
In the linguistic case, what sometimes seems to underpin people's positions on such issues is differing intuitions as to who has the burden of proof in this debate. Empiricists or non-nativists contend that Chomskyans have not presented enough data or considered enough alternative hypotheses to establish their case. Chomskyans reply that they have done more than enough, and that the onus is on their critics either to produce data disconfirming their view or to produce a testable alternative to it.
That such burden-shifting is endemic to discussions of linguistic nativism the exchange in Ritter is illustrative suggests to me that neither side in this debate has as yet fulfilled its obligations. Empiricists about language acquisition have ably identified a number of points of weakness in the Chomskyan case, but have only just begun to take on the demanding task of developing develop non-nativist learning theories, whether for language or anything much else.
Nativists have rested content with hypotheses about language acquisition and innate knowledge that are based on plausible-seeming but largely unsubstantiated claims about what the pld contain, and about what children do and do not know and say. It is unclear how to settle such arguments. While some may disagree especially some Chomskyans , it seems that much work still needs to be done to understand how children learn language — and not just in the sense of working out the details of which parameters get set when, but in the sense of reconceiving both what linguistic competence consists in, and how it is acquired.
In psychology, a new, non-nativist paradigm for thinking about language and learning has begun to emerge over the last 10 or so years, thanks to the work of researchers like Elizabeth Bates, Jeffrey Elman, Patricia Kuhl, Michael Tomasello and others. The reader is referred to Elman et al. For now, considerations of space demand a return to our topic, viz.
We saw in the previous section that in order to support the view that all of UG is innately known, nativists about language need to hold not just that the data for language learning is impoverished in a few isolated instances, but that it's impoverished across the board. That is, in order to support the view that the innate contribution to language acquisition is something as rich and detailed as knowledge of Universal Grammar, nativists must hold that the inputs to language acquisition are defective in many and widespread cases.
After all, if the inputs were degenerate only in a few isolated instances, such as those discussed above, the learning problem could be solved simply by positing innate knowledge of a few relevant linguistic hints, rather than all of UG. Pullum and Scholz helpfully survey a number of ways in which nativists have made this point, including:.
In this section, I will set aside features i and ii as being characteristic of any empirical domain: the data are always finite, and they always underdetermine one's theory. No doubt it's an important problem for epistemologists and philosophers of science to explain how general theories can nonetheless be confirmed and believed. No doubt, too, it's an important problem for psychologists to explain the mechanisms by which individuals acquire general knowledge about the world on the basis of their experience.
But underdetermination and the finiteness of the data are everyone's problem: if these features of the language learning situation per se supported nativism, then we should accept that all learning, in every domain, requires inborn domain-specific knowledge. But while it's not impossible that everything we know that goes beyond the data is a result of our having domain-specific innate knowledge, this view is so implausible as to warrant no further discussion here. I also set aside features iii and iv.
For one thing, it is unclear exactly how degenerate the pld are; according to one early estimate, an impressive And even if the data are messier than this figure suggests, it is not unreasonable to suppose that the vast weight of grammatically well-formed utterances would easily swamp any residual noise.
As to the idiosyncrasy of different children's data sets, this is not so much a matter of stimulus poverty as stimulus difference. As such, idiosyncrasy becomes a problem for a non-nativist only on the assumption that different children's states of linguistic knowledge differ from one another less than one would expect given the differences in their experiences. As far as I know, no serious case for this last claim has ever been made. In this section, we will focus on features v and vi of the pld.
Figure 2. Five possible relations between the language generated by hypothesis H and the target grammar L. Take a child learning the grammar of her language, L. Figure 2 represents the 5 possible relations that might obtain between the language generated by her current hypothesis, H , and that generated by the target grammar, L.
A learner in situation i , ii or iii is in good shape, for she can easily use the pld as a basis for correcting her hypothesis as follows: whenever she encounters a sentence in the data i. In this way, H will keep moving, as desired, towards L. However, suppose that the learner finds herself in situation iv , where her hypothesis generates all of the target language, L , and more besides. There, she is in deep trouble, for she cannot use the pld to discover her error.
Every sentence of L , after all, is already a sentence of H. For as we have seen, the pld is mostly just a sample of sentences, of positive instances of the target language. It contains little, if any, information about strings of words that are not sentences. For instance, children aren't given lists of ungrammatical strings.
Nor are they typically corrected when they make mistakes. And nor can they simply assume that strings that haven't made their way into the sample are ungrammatical: there are infinitely many sentences that are absent from the data for the simple reason that no-one's had occasion to say them yet. Negative evidence, however, does not appear to exist. There are two ways they could do this. One would be never to generalize beyond the data at all. But clearly, children do generalize, else they'd never succeed in learning a language. The other would be if there were something that ensured that when they generalize beyond the data, they don't overgeneralize , something, that is, that ensures that children don't make errors that they could only correct on the basis of negative evidence.
According to the linguistic nativist, this something is innate knowledge of UG. Second, let's abandon the idea, which reappears in many presentations of the Argument from the Unlearning Problem; that learners' hypotheses must be explicitly falsified in the data in order to be rejected. Let's suppose instead that learners proceed more like actual scientists do — provisionally abandoning theories due to lack of confirmation, making theoretical inferences to link data with theories, employing statistical information, and making defeasible, probabilistic rather than decisive, all-or-nothing judgments as to the truth or falsity of their theories.
Intuitively, viewing the learner as employing more stochastic and probabilistic inductive techniques enables one to see how the unlearning problem might have been overblown. What the argument claims, rightly, is that negative data near enough do not exist in the pld. However, what learners need in order to recover from overgeneralizations, is not negative data per se , but negative evidence , and arguably, the pld do contain significant amounts of that. For example:. Non-occurrence of structural types as negative evidence : Suppose that a child's grammar predicted that a certain string is part of the target language.
Suppose further that that string never appears in the data, even when the context seems appropriate. Proponents of the unlearning problem say that non-occurrence cannot constitute negative evidence — maybe Dad simply always chooses to say The girl who is in the jumping castle is Kayley's daughter, isn't she? If so, it would be a mistake for the child to conclude on the basis of this information that the latter string is ungrammatical. But suppose that the child is predicting not strings of words, simpliciter , but rather strings of words under a certain syntactic description or, perhaps more plausibly, quasi-syntactic description — the categories employed need not be the same as those employed in adult grammars.
For non-occurring strings will divide into two broad kinds: those whose structures have been encountered before in the data, and those whose structures have not been heard before. In the former case, the child has positive evidence that strings of that kind are grammatical, evidence that would enable her to suppose that the non-occurrence of that particular string was just an accident. Again, the evidence is not decisive, and the child should be prepared to revise her grammar should strings of that kind start appearing.
Nonetheless, the non-occurrence of a string, suitably interpreted in the light of other linguistic information, can constitute negative evidence and provide learners with reason to reject overgeneral grammars. Positive Evidence as Negative Evidence. Relatedly, learners can also exploit positive evidence as to which strings occur in the pld as a source of negative evidence — again in a tentative and revisable way. The fact that only strings of the first kind occur is in this case negative evidence — defeasible, to be sure, but negative evidence nonetheless. In fact, the use of positive evidence to disconfirm hypotheses is endemic to science.
For instance, Millikan used positive evidence to disconfirm the theory that electrical charge is a quantity that varies continuously. However, more recent findings have uncovered evidence indicating that failures of understanding occur with some regularity, and that there is a wealth of feedback about correct usage in the language-learning environment. However, he concluded that they were too few and ambiguous to be of aid to the language learner. The sorts of findings reported above seem to show that negative evidence is pervasive in the pld. But can children learn from these sorts of statistical regularities?
Given such a conception of the learner, none of the examples of feedback just discussed will seem relevant to the problem. For only a learner employing fairly sophisticated data-analysis techniques and a confirmation measure that is sensitive to small changes in probabilities would be able to exploit the sorts of regularities in the linguistic environment that we have just discussed. However, there is increasing evidence that children are in fact remarkably sensitive to subtle feedback, in both linguistic and non-linguistic domains.
For instance:. In addition, it is becoming increasingly clear that babies, children, adults and many other mammals are highly sensitive not just to feedback, but to other non-obvious statistical regularities in their experience. Taken together, these kinds of results raise the possibility that some of the foundational learning mechanisms involved in language acquisition are not language specific.
If it turns out that babies employ the sorts of distributional analysis studied by Saffran, Redington and Chater, Pena, and Mintz not only in learning artificial languages, but also in learning natural languages, then that is evidence against linguistic nativism. For this type of learning is employed by humans and other animals in other contexts as well: whatever is involved in language learning — be it innate or not — is not language-specific. The previous objections to the Unlearning Problem Argument made the points, first, that negative evidence does exist in the pld in the form of regularities both in others' language use and in how others react to children's own productions , and second, that children and other animals seem very good at exploiting this kind of information for the purposes of learning about their world.
This would seem to be rather a good thing, given that there is reason to think that learners must be able to learn in domains where explicit negative data do not exist, and in the absence of specialized innate knowledge of those domains. For the unlearning problem is a problem for learning from experience quite generally. That is, there are many domains in which learners lack explicit evidence as to what things are not : trees are not cars, Irish stews are not curries, birds are not fish and MacDonald's is not a branch of the CIA.
Clearly, in at least some areas, people are able to learn an awful lot on the basis of largely positive data, and while this of course does nothing to show that language is one of those areas, it does indicate that the Unlearning problem argument by itself is no argument for linguistic nativism at all, let alone for the Chomskyan UG-based version of that position. In this section, I will mention some other avenues of research that have been argued to have a bearing on the innateness of language. My goal is not to give an exhaustive survey of these matters, but rather to provide the interested reader with a way into the relevant literatures.
Chomsky and others e. Universals are features thought to be common to all natural languages, such as the existence of constraints on the movement of elements during a derivation or, less controversially, the existence of a syntactic distinction between nouns and verbs. But not only is the existence of true universals a contested matter see e. One explanation is certainly the Chomskyan one that they are consequences of speakers' innate knowledge of UG.
Another is that they derive from other, non-linguistically-specific features of cognition, such as memory or processing constraints e. Yet another is that they derive from universal demands of the communication situation e. Finally, as Putnam speculated, universals might be relics of an ancestral Ur-language from which all other languages evolved.
This last hypothesis has generally been rejected as lacking in empirical support.
- THE DAY THEY SHELLED SCARBOROUGH | Yorkshire Film Archive.
- Remember Scarborough A Result of the First Arms Race of the Twentieth Century UK ed.;
- All Ill Ever Need (Indigo).
- Quicklet On Oscar Wildes The Importance of Being Earnest.
However, recent findings in genetics and historical linguistics are converging to suggest that all human populations evolved from a small group migrating from Africa in the fairly recent past, and that all human languages have probably evolved from the language spoken by that group. Cavalli-Sforza The Ur-language hypothesis is not, of course, inconsistent with linguistic nativism. However, if true, it does weaken any argument from the existence of universals to the innateness of linguistic knowledge.
For if languages have a common ancestor, then it is possible to explain universals — even ones that seem strange from a functional point of view — as being the result of our ancestors' having adopted a certain solution to a linguistic coordination problem. More plausible would be the supposition that the different groups' choice of the rule was driven by something internal to speakers , such as, perhaps, an innate representation of UG.
If they don't, then such universals seemingly could only be explained in terms of features internal to speakers. Beginning with the work of Broca and Wernicke in the 19th century, a popular view has been that language is localized to certain areas of the brain see Fig. The fact that syntax can apparently be selectively interfered with by lesions to Broca's area has been taken by some to indicate that grammatical knowledge is localized to that area, and this in turn has been taken to show support the view that there is a special biological inborn basis for that knowledge.
Lenneberg , is the original proponent of this argument, which is echoed in more recent discussions, such as Pinker It is unclear, however, why this inference should seem compelling. First, as Elman et al. Secondly, it is now known that neural localization for language is very much a relative, rather than an all-or-nothing matter Dronkers et al. Not only is language processing widely distributed over the brain see Fig. Maess et al. Finally, recent studies of cortical plasticity have shown that even the most plausible candidates for innate specification — such as the use of visual cortex for vision or the use of auditory cortex for hearing — exhibit high degrees of experience-dependent plasticity.
For example, in congenitally blind subjects, the areas of the brain normally used for seeing are taken over for the processing of Braille Sadato et al. Likewise, in the congenitally deaf, auditory cortex is used for the processing of sign language Nishimura et al. See Shimojo and Shams , for a review.
Figure 4. Pet scan showing brain regions involved in various language tasks. From Posner and Raichle , Used by permission of M. As Marcus points out in response to Elman et al. This suggests that these abilities require little in the way of task-specific pre-wiring, and are learned largely on the basis of experience together with whatever sort of 'prewiring' is supplied for the cortex as a whole. That is, if sign language processing tasks can be carried out by areas of cortex that are presumably innately predisposed if they are to do auditory processing, then the former competence must be being learned in the absence of inborn constraints or knowledge that are specific to that task.
Nonetheless, examples like these provide an existence proof of the brain's ability to acquire complex processing capacities — indeed, processing capacities relevant to language — in the complete absence of inborn, domain-specific information. As such, they raise the possibility that other aspects of language processing are similarly acquired in the absence of task-specific constraints. In sum, the neuroscientific evidence currently available provides no support for linguistic nativism.
The suggestion that localization of function is indicative of a substantial degree of innate prespecification is no longer tenable: localization can arise in many different ways. In addition, linguistic functions do not seem to be particularly localized: language use and understanding are complex tasks, involving many different brain areas — areas that are in at least some cases implicated also in other tasks. This is not, of course, to say that language is one of the competences that are acquired in this way.
It is, however, to suggest that although there may be other reasons to be a linguistic nativist, general considerations to do with brain organization or development as currently understood give no especial support to that position. On analogy with other supposedly innately specified processes like imprinting or visual development, Lenneberg used the existence of a critical period as further evidence that language possesses a proprietary basis in biology. In support of the critical period hypothesis about language, Lenneberg cited the facts i that retarded e.
As further support for the critical period hypothesis, others have added the observation that although children are able to learn a second language rapidly and to native speaker fluency, adult learners of second languages typically are not: the capacity to learn a second language tapers off after puberty, no matter how much exposure to the language one has.
Newport Thus, it was speculated, the innate knowledge base for language learning e. Johnson and Newport Critical Period : a time during development which is literally critical; the relevant competence either cannot develop or will be permanently lost unless certain inputs are received during that period.
The classic example of a critical period is due to the Nobel prize-winning work of Hubel and Wiesel. By suturing shut one of a kitten's eyes at various stages of development and for various periods of time, Hubel and Wiesel showed that certain cortical and thalamic areas supporting binocular vision specifically, ocular dominance columns [ 20 ] and cells in the lateral geniculate body will not develop normally unless kittens receive patterned visual stimulation during the 4th to 12th weeks of life.
They found that while the damage was sometimes reversible to some extent, depending on the exact duration and timing of the occlusion, occlusion for the entire first three months of life produced irreversible blindness in the deprived eye. Language, however, is not like this. As we will see, there is little evidence for a critical period for language acquisition, although there is considerable evidence that there is a sensitive period during which language is acquired more easily. Lenneberg cited the superior ability of children to re learn language after left brain injury in support of the critical period hypothesis.
But while there clearly is a difference between the abilities of young children, on the one hand, and older children and adults, on the other, to recover from left brain insults, the contrast in recovery course and outcome is not as stark as is often supposed. Vargha-Khadem et al. After his left cortex was removed at age 9, Alex suddenly began to learn language with gusto, and by age 15, his skills were those of an year old.
Secondly, most adults suffering infarcts in the left hemisphere language areas do in fact recover at least some degree of language competence and many recover substantially normal competence, especially with treatment Holland et al. This is thought to be due both to the regeneration of damaged speech areas and to compensatory development in other areas, particularly in the right hemisphere Karbe et al.
Similar processes seem to be at work in young children with left hemisphere damage. Muller et al.
Yorkshire Hussars in Scarborough - Places & Infrastructure - Great War Forum
Finally, not even very young children are guaranteed to recover language after serious insults, whether to the left or right hemisphere. As Bates and Roe argue in their survey of the childhood aphasia literature, outcomes differ wildly from case to case, and the reported studies exhibit numerous methodological confounds e.
However, in work pioneered by Goldin Meadow and colleagues e. Studies of what happens to such children after they are exposed to natural languages signed or verbal at various ages promise to offer new insights into the critical and sensitive period hypotheses. At this time, however, there are still very few case reports in the literature, and the data so far obtained in these studies are equivocal with respect to the sensitive and critical period hypotheses.
Some adolescents do seem to be able to acquire language despite early linguistic deprivation, and others do not. It is unclear what the explanation of these different outcomes is, but one important factor appears to be whether the new language is a signed language e. Perhaps because their childhood perceptual deficits prevented normal auditory and articulatory development, deaf children whose hearing is restored later in life do not seem to be able to acquire much in the way of spoken language.
Grimshaw et al. For instance, Johnson and Newport found that among immigrants arriving in the U. The fact that the amount of exposure to the second language mattered for speakers if it occurred before puberty but not after, was taken to confirm the critical period hypothesis. Flege, Yeni-Komshian and Liu ; Bialystok, [ 22 ]. The fact that many adults and older children can learn both first and second languages to a high degree of proficiency makes clear that unlike the kitten visual system studied by Hubel and Wiesel, the language acquisition system in humans is not subject to a critical period in the strict sense.
This finding is consistent with the emerging view that the cortex remains highly plastic throughout life, and that contrary to received wisdom, even old dogs can be quite good at learning new tricks.
It is also consistent with the idea, which seems more plausible than the critical period hypothesis, that there is a sensitive period for language acquisition — a time, from roughly birth age 1 to age 6 or 7, in which language is acquired most easily and naturally, and when a native-like outcome is virtually guaranteed. Mayberry and Eichen The implications of this conclusion for linguistic nativism are examined in the next section. What does the existence of a sensitive period for language mastery tell us about the innateness of language?
In this section, we will look at a case, namely phonological learning, in which the existence of a sensitive period has received much press, and in which the inference from sensitivity to the existence of language-specific innate information has been made explicitly see Eimas One can argue that even in this case, the inference to linguistic nativism is weak.
THE DAY THEY SHELLED SCARBOROUGH
Much rarer than mastery of second language morphology and syntax is attainment of a native-like accent, something that first language learners acquire automatically in childhood. In the first few months of life, babies reliably discriminate many different natural language phonemes, whether or not they occur in what is soon to become their language. By ages 6 months to 1 year, however, this sensitivity to unheard phonemes largely disappears, and by age 1, children tend to make only the phonological distinctions made in the language s they hear around them.
As adults, people continue to be unable to perceive some phonetic contrasts not marked by their language, and many fail to learn how to produce even those second language sounds which they can distinguish. If you have any problems with your order please contact us first before leaving feedback and our excellent customer service help to resolve the issue.
We offer a 30 day no quibble money back guarantee. Payments We currently only accept immediate payment by PayPal for all eBay orders. Payment must be received before items can be despatched. Western Europe deliveries are expected to arrive between business days. All other international deliveries are expected to arrive between business days. Returns Your satisfaction is very important to us.