Abstract
This paper gives a survey of some of the major properties of and approaches to the Optional Infinitive stage of linguistic development. After a brief account of its first discovery, a description is given of some of its major properties, including rates of OI production and how they change over time and vary cross-linguistically. “Surfacy” accounts of the stage are considered, such as the possibility that the use of the root infinitival where it doesn’t belong is a kind of phonological simplification. Some attention is also devoted to the possibility that the OI stage arises from the omission of an auxiliary. Evidence argues against these approaches. Instead, radical omission models, in which the features of Tense (and possibly other inflectional elements) are totally missing from the phrase-marker for an OI, are argued to hold most promise. Considerations of relations of subject case and OI’s lead to the formulation of the ATOM model to describe the stage. Empirical evidence is provided in support of the Null Subject/OI correlation, including a detailed discussion of recent papers on Italian and Dutch. Both papers investigate large numbers of children. Two major contenders for the best approach to the OI stage are described: the Truncation model and the Unique Checking Constraint (UCC) model. The empirical evidence favors the UCC. If the UCC is the best theory, how does it go away so that children become linguistic adults? It is argued that only a biologically based maturation theory can account for the data, and some recent genetic results bolster this argument. The paper discusses empiricist approaches to the problem of OI, devoting most attention to a recent attempt to explain the existence of the OI stage as arising from difficulties in a child’s learning that his/her language has Tense. It is argued that the approach fails to predict the central phenomena of the OI stage and that the traditional representational/growth models fare best. To demonstrate the wide empirical applicability of the proposed model of early syntactic development, extensions to properties of the syntactic object system are suggested, such as clitic omission cross-linguistically and short-form negation errors in Korean as well as the question of to and be omission in this stage.
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- 1.
One voice against that was Hyams (1992), who argued, against much opposition, that young Italian children knew much about inflectional morphology. Hyams hadn’t observed root infinitives, however. The fact that her arguments were about Italian would have made these observations difficult, as we will see.
- 2.
The verbs were considered infinitival because they had the form/phonetics of an infinitive, not a finite form, e.g. attraper in (2b). In French, the infinitive of 1st conjugation verbs like attraper has the same phonetic form as the past participle, so it might be thought that the verb was a participle with the auxiliary missing. Even if this were true, the word order facts that are predicted will be the same. That is, the participle (like the infinitive, but unlike the finite form) comes after pas. Many languages have infinitives that are phonetically different than the participle, so this issue won’t arise. Even in French, Wexler (1993) shows that there are many 2nd and 3rd conjugation French root infinitives in Pierce’s data, despite that fact that they are phonetically different from participles (e.g. dormir, where the participle is dormi or voir where the participle is vu). Levow (1995) does a careful analysis of French corpora and concludes that even for the 1st conjugation verbs, there are many infinitives as well as many participles.
- 3.
The OI stage is equally known as the Root Infinitive stage. This distinction is purely terminological, depending on whether one wishes to emphasize the possible simultaneous existence of finite verbs or the fact that the relevant verbs are in the root. One might even name the stage the Optional Root Infinitive stage, another piece of terminology. In fact, as Wexler (1993) suggested might exist, and as Wijnen (1998) has since argued for very early Dutch, there might even be early periods in which only non-finite verbs appeared in the corpus. On the other hand, there is good evidence, to be discussed later, that child tense omission occurs in embedded sentences, sentences that should be finite for adults, showing OI phenomena in non-roots. The general property that clearly holds is that the child uses non-finite verbs in constructions where the adult must use a finite verb. The OI stage is the simple name for this phenomenon.
- 4.
And even in those that don’t. See Cable (2005) for evidence for the OI stage in Afrikaans, a language with extremely little overt agreement or tense marking on the main verb. Cable argues on the basis of the OI stage in Afrikaans that Tense and Agreement exist syntactically in that language. He writes, “Afrikaans is well-known for being the least inflected of the Germanic languages … [T]here exists no marking of agreement in number or person on Afrikaans verbs or adjectives …. Whatever number or person the subject of an Afrikaans sentence has, the verb assumes the same, invariant form. Afrikaans also possesses a relatively reduced system of tense morphology. All main verbs have a past participial form, which is used in conjunction with the past auxiliary het to express past tense. Furthermore, there are only two verbs in Afrikaans that have a distinct form in the infinitive: “wees” (to be) and “hê” (to have; main verb). All other verbs in Afrikaans possess a single invariant form, used for both non-finite and finite present tense clauses.” After going through the evidence for an OI stage in Afrikaans, Cable concludes, “At a more basic level, the existence of the OI-Stage in child Afrikaans solidifies the general conclusion that the OI-Stage is rooted in abstract, syntactic properties of a language, and not in its superficial morphological details.”
- 5.
See Avrutin (1997) for the use of root infinitives in adult Russian, and an attempt to relate OI’s to these.
- 6.
He cited research on German, Dutch, English, Danish, Norwegian and Swedish. We will return to the discussion of English.
- 7.
A minority of V2 languages also move the verb in embedded clauses, but they are not relevant here.
- 8.
From Wexler et al. (2004b).
- 9.
Only main verbs, not auxiliaries and copulas are counted, because it is known that auxiliaries and copulas do not become infinitival in tensed contexts. Rather, they are omitted. We will return to the theoretical explanation of this phenomenon.
- 10.
We have shown the distribution of OI’s by age; the paper also shows the distribution by MLU.
- 11.
Except, perhaps for a model like Radford’s (1990a, b) “no functional categories” model, in which it is assumed that the youngest children have no functional categories at all. Even in Radford’s data, however, there were productions that looked as if they needed functional categories to derive forms which Radford had to find ways to explain.
- 12.
Or that the child hadn’t learned the finite inflection at that extremely early age. The question then would be: why has the child learned the infinitival inflection but not the finite inflection? This is especially relevant in a language in which some finite forms are zero but the infinitival isn’t.
- 13.
V1 means the verb is in first position. Analyses of the OI stage of Germanic languages, Dutch in particular, standardly treat these as correct verb placement, as V2, with a topic-drop or other reason for omission of the first position (Wexler et al. 2004a, b). Dutch in fact does topic-drop fairly enough, so that V1 sentences do occur often. We’ll discuss later Yang’s (2002) claim that in fact V1 occurs in child productions because the child analyzes Dutch as a Semitic-style V1 language. This is surprising to Dutch linguists, who hear these sentences as typically Dutch for the most part.
- 14.
It is well-known that verbs that should be infinitival are produced by children correctly in the OI stage. See, for example, Lorusso, Caprin and Guasti (2005) Italian study.
- 15.
And, of course, there might be interesting differences in the patterns of errors; one suggestive possibility is that there are a higher (though still very small) proportion of errors leaving a finite verb in final position in main clauses of SOV/V2 languages than moving an infinitival verb into second position. Richer data and analyses are needed.
- 16.
Except perhaps for the work of Yang (2002) that has been already noted. Yang, though, doesn’t disagree with the child data. Rather, he doesn’t accept the standard assumption that V1 utterances in Dutch exist as a kind of topic-drop so that he thinks V1-first utterances show that the Dutch child doesn’t know the word order parameters.
- 17.
Though see Hyams’ (1992) analysis of Italian agreement, which argues for good knowledge. Many scholars, though, including Hyams, thought that only rich agreement languages like Italian showed this good knowledge. Poeppel and Wexler suggested that it was more far-reaching, and Wexler (1998) proposed the generalization: Very Early Learning Of Inflection.
- 18.
This is too simple; distributed morphology probably makes the learning task easier, but we don’t have space to discuss this issue here.
- 19.
Hebrew (like Czech) is an interesting mixed case, being OI in some part of the paradigm but not others. See Wexler (1998) for discussion and references.
- 20.
The calculation for Italian: The Italian kids produce 1,079 present indicative forms and 264 “other tense” forms. Adding, we get 1,343 finite forms of main verbs (not counting verbs with aux (passato prossimo), imperatives, past participles, gerunds or “governed” (non-root) infinitives). There are 31 RI’s at best. Thus the rate of OI’s for Italian is 31/(1343 + 31) = 31/1374, approximately 2%. For Dutch, from (7) there are 626 RI’s and 2,590 total verbs, making the OI rate 626/2,590 = 24%.
- 21.
In fact, Caprin and Guasti’s G1 are the slowest (in terms of MLU) developing Italian group, so that we’re comparing a slow-developing Italian group to a group of Dutch kids of the same age who aren’t selected for being slow. Thus if there were no difference in how OI’s develop, we’d expect more OI’s in the Italian, since, given the mean age, it’s a somewhat slow-developing group. Wexler, Schaeffer and Bol also do an analysis of OI rate in terms of MLU. As usual, we can’t really compare kids cross-linguistically on the basis of MLU. MLU’s measured in particular ways vary a great deal based on the particular properties of the language; this is well understood. Thus the best comparison is via age. Any more or less reasonable MLU analysis, if it could be given, would confirm the result of course.
- 22.
See also Sano and Hyams (1994).
- 23.
We say main verbs, because other properties of the OI stage (like auxiliary omission) might exist even in a null-subject language, as Wexler (1998) argues.
- 24.
The proportions of OI’s in Russian are relatively small, though they exist in sufficient numbers to warrant the conclusion that Russian is an OI language (Bar-Shalom and Snyder 1997). We don’t know enough about why the numbers of Russian OI’s are small.
- 25.
Of course, OI’s can exist in English with other person/number combinations. The form of the verb, however, will be identical to the finite form. The form of subject case, we’ll see, will help us to see OI’s in these other person/number combinations.
- 26.
To simplify, we’ll ignore genitive/possessive relations and marking.
- 27.
We put scare quotes around “error” because we’ll see that what children do isn’t an error after all.
- 28.
This fact is one of many that show that the purely phonological view of OI’s – that children really take them as finite, but drop-off endings – in English is on the wrong track. If OI’s in English were finite, but phonetically reduced, why should they (and only they) allow what appear to be ACC subjects, i.e. forms like (11)?
- 29.
There is a serious question about whether both AGR and TNS can be omitted in the OI stage and what behavior that would lead to. For simplicity in this paper, we will assume that only one of these projections can be omitted in the OI stage.
- 30.
This is a descriptive statement. Much of the latter part of Wexler (1993) is devoted to attempts to derive (16) from more fundamental considerations. We will not describe those, but will take another more fundamental computational approach in later sections.
- 31.
See Cable (2005) for arguments that Afrikaans, a language with almost no verbal inflection goes through an OI stage, together with arguments from these developmental data that grammatical processes involving inflection operate even when the inflection is phonetically zero.
- 32.
- 33.
It happens in L2; that’s why L2 looks so different, why it doesn’t go through the OI stage, in adults and even children older than the OI-age.
- 34.
The issue of the meaning of OI’s, especially of whether they have to be modal, is complex. We’ll return to that.
- 35.
We will return to a large variety of other facts that UCC explains.
- 36.
For the purpose of explaining the OI facts under consideration in this section, one could assume the older VP, with the subject in its spec, ignoring the vP. We assume the vP here, not only because of its wide acceptance, and the reasons for its acceptance, but because it will be useful (perhaps necessary) later in explaining the UCC’s application in the case of clitic omission, scrambling and short-form negation in Korean.
- 37.
Often it is argued, perhaps on Minimalist grounds, that AGR is not an independent projection. But the evidence isn’t so clear, and there are approaches that project AGR independently. It’s also probably possible to replicate the results I will described within a system that has only an INFL projection, both both tense and agreement features. Research along these lines would be valuable.
- 38.
Languages like Chinese are usually thought to lack Tense and Agreement on the surface. Whether they actually lack these in a deeper sense is much less clear, and possibly the dominant linguistic view is that they don’t.
- 39.
- 40.
In much recent work, topics and wh-phrases go into different positions. In order to simplify, I am ignoring such theoretical differences. They might potentially help with the current problem, if we had the right idea.
- 41.
- 42.
For example, Roberts (1997) writes, “It is particularly interesting that, from the moment that subordinate clauses begin to appear in Adam’s speech, several different kinds appear at the same time. There seems not to be a period n which one kind of subordinate clause is learned, then another, and so on. An exception, however, is the class of unambiguously finite complements, which appear only rarely; for example, (9c) Go belong (which Adam’s mother interprets as Go where it belongs).” It’s worth remarking that this one very rare clause that is interpreted as a finite utterance seems to be an embedded OI with a null-subject and a missing wh-phrase. Roberts finds a total of seven complements that should be finite in the two children that he studies; none of them are inflected. But these are too few to form a conclusion from. It is suggestive, however, of the conclusion that OI’s exist in embedded clauses. As extensive a study as possible of OI’s in embedded clauses that should be finite would be welcome.
- 43.
Tom Roeper (p.c.) points out that children never say I want/don’t want, but always I want to/I don’t want to, asking whether this is a counter-example to the conclusion that to is omitted by children in the OI stage. Although I don’t know of any studies, this statement about child productions feels as if it may be right. If so, the question is: why isn’t to omitted in this type of VP ellipsis even though it’s omitted in non-ellipsis contexts? It seems that there is a quite likely explanation. Note that an elided VP must be governed by Tense. Small clauses (Mary leave in I made Mary leave) don’t contain tense. It seems that small clauses VP’s can’t undergo this same VP ellipsis process.
-
(i)
Speaker 1: John left early
-
(ii)
Speaker 2, in response: *I saw/made Sue (i.e., cannot mean I saw/made Sue leave early).
There is no VP ellipsis of the VP in the small clause. Compare to the possibility of VP ellipsis in the infinitival clause.
-
(iii)
Speaker 1: John left early
-
(iv)
Speaker 2, in response: I want Sue to (i.e. means I want Sue to leave early)
There is VP ellipsis in the infinitival. Infinitival to is standardly assumed to occupy the head of the Tense projection; it is “infinitival” tense. So infinitival to (Tense), locally commands the VP and licenses VP ellipsis. In the small clause (ii), however, there is no Tense (no finite Tense, no infinitival Tense (to)) so Ellipsis is not allowed. All we have to assume is that the young child knows this condition on VP ellipsis, and we predict Roeper’s interesting observations. If this is one the right track, we have further evidence for radical omission: omitting to means that the whole Tense projection is omitted, therefore disallowing VP ellipsis. (E.g., aux-omission couldn’t predict such a fact, since the syntactic features (Tense) remain). Further empirical studies and theoretical analysis will be useful.
-
(i)
- 44.
At the time of Roberts’ writing, the ATOM and UCC had not yet been proposed, nor were the case facts yet part of the OI discussion, so the Tense Omission hypothesize was clearly the one to consider. It is of course equally clear that ATOM and the UCC are supported vis a vis Truncation.
- 45.
In this table, the data from one child, Nathaniel, is omitted because he seemed atypical; his to-omission extended somewhat longer than the other children. Norris also provides the data with Nathaniel included. It doesn’t change much, just a bit higher percentages of to-deletion, especially at the older ages.
- 46.
Norris writes, “When there are not enough data points to produce a statistically significant percentage, the computed percentage is in parentheses.”
- 47.
Norris shows that most of the late to-omission is from one child, Adam. Since there aren’t many older children in the study, Adam counts disproportionately. Adam is often considered to have somewhat atypical, even delayed language. Norris concludes that to drops off before 4;0, both in PRO subject clauses and in LS clauses.
- 48.
In particular, Borer and Wexler proposed the Triggering Problem. Why does evidence apply at one age and not an earlier age. Babyonyshev et al. (2001) called this the Argument from the Abundance of the Stimulus. The evidence in the case they studied was so prevalent in the input, it was very difficult to see why learning should be delayed.
- 49.
Of course, the measure has to be one for which it is reasonable to assume that parents don’t treat identical twins more alike than they treat fraternal twins (as might be the case, for example, in clothing choice). It is hard to think of any cognitive measure that is less likely than production of finiteness (by parents) to have the wrong property, i.e. a situation whereby parents tended to use the same proportion of finite utterances with identical twins, but varied their finiteness proportions more for fraternal twins. If behavioral genetics is appropriate for any cognitive behavior, it is appropriate for OI’s.
- 50.
Given our conclusions, is not finiteness that is under genetic control. Rather it is the withering away of UCC that is under genetic control. In other words, a particular computational limitation on the child’s grammar dies away under genetic control.
- 51.
Wexler (1999) argued that in fact “continuity” is a misleading name for this concept. He argued that the claim that there was no genetically controlled growth of the linguistic capacity should rather be called “Rigidity.” “Continuity” would better be reserved for the claim that there is a strong genetic basis to UG, with some small maturational changes in capacity as in e.g. the withering away of UCC, or (on another topic, not discussed here), the dieing away of the Full Phase Requirement (Wexler 2004).
- 52.
Furthermore, as Rizzi (1993) points out, if a child’s UG is identical to an adult’s, then linguistic theory can’t learn much from acquisition, except confirmation. But if a child’s UG has slight “perturbations” from UG, then child language can provide a kind of “experiment” that shows what happens under these perturbations, providing a potentially rich source of evidence for linguistic theory. There are already many examples in the literature. Consider, for example, what the OI stage tells us about the relation of case and finiteness, and default case, as in the work of Schutze and Wexler (1996). We see there that a main verb without agreement in child English can elicit the “default” non-nominative case: her go, whereas in child Dutch or German, the equivalent non-nominative subjects won’t exist for the OI”s, prevalent as these OI’s are, because the default case in those languages is nominative. The English cases are quite rare in the adult, existing only in “exhortative” sentences and similar (her/*she go to California? Never!) but they are a well-known feature of early linguistic development in ordinary declaratives in young children in the OI stage. Thus this possibility of often leaving out an agreement feature from a phrase-marker during the OI stage, this slight “perturbation” of UG, provides a lovely source of evidence about the interaction of subject case and finiteness.
- 53.
Biology should also have expected this result, but biology, for the most part, knew so little of language, that nothing much was said, for the most part. There were a few exceptions, but without experimental detail. Lenneberg (1967) did expect this kind of result, in a direct way. He was much influenced by Chomsky’s arguments about generative grammar as well as biology. We wouldn’t expect (mainstream) psychology to expect this kind of result, as its foundations are completely different, presuming an associationist, empiricist model as axiomatic.
- 54.
The approach of Gibson and Wexler (1994) followed the basic strategy of Wexler and Culicover (1980) of seeing how much could be learned via a strong UG system and a simple learning system, so that the computational “learning” problem was simple. This was also in line with the ideas that introduced parameters into linguistic theory – that they helped to solve the tension between language variation and language learning by making the learning problem so simple (setting a parameter via simple data, in a simple way) given the strong UG, that the data would make the learning take place easily. Gibson and Wexler showed that even in an extremely simple three-parameter system, this vision wasn’t realized, so that more structure would have to be added to the problem. To not take into account the limited abilities of the child (or even adult) in doing computations (2 to the 40 grammars to consider?) seems to miss the point of parameters. How it is “feasible” (Chomsky 1965) to set parameters, that is, to set them within human capacities regarding memory, storage, access to data and so on?
- 55.
The term stems, presumably, from Manzini and Wexler’s and Wexler and Manzini’s Independence Principle, which explicitly gives a formal definition of independence of parameters in order to make the Subset Principle work in the multi-parameter case.
- 56.
Except exhortatives, etc., that we already discussed. Legate and Yang acknowledge that these shouldn’t count; they have a very different semantics – the problem is, why adults eventually produce no OI’s in more standard contexts.
- 57.
It’s only 2 because this paper doesn’t study more than this one parameter.
- 58.
All of Legate and Yang’s arguments depend on the learner knowing whether or not a morpheme is a + Tense morpheme, e.g. that ed marks past tense. They don’t show how this can happen despite the OI stage, but simply assume this knowledge. However, what could it mean for the learning theory to both learn ed as + Past and not know that the language is a + Tense language? There are many other considerations and unclarities that could possibly be answered by a simulation that put a few properties into the system to be learned. Given that the paper only presents some aspects of the computation of whether + Tense or –Tense holds, we don’t know what would happen. My own theoretical hunches and long-time experience in learning theory lean me toward guessing that all this can’t work, that the arguments can only be made in the absence of studying the interaction. Of course we don’t know for sure until the analysis is done. We should hope that the believers in such models do an analysis of this kind. The central point of Gibson and Wexler (1994) and what made its results so widely attended to, with alternative systems attempted, was that it studied a system of linguistic parameters together, highlighting the interaction problems. Since then, learning theory has known that systems of parameters have to be studied in order to not miss the central issues. The one-parameter problem distorts the situation qualitatively, not just quantitatively.
- 59.
Even Gibson and Wexler’s (1994) Triggers model, which was attempting to capture what linguists meant by “simple” learning of parameters (using “triggers”) said that if the child could generate a sentence, the parametric value wasn’t changed. Yang’s theory, however, pushes down the alternative value—thus data that is truly irrelevant can make the language learner go the wrong way. This happens a great deal – when there is ambiguous data. This is the basis for the very slow learning of the model.
- 60.
As we discussed earlier, Hyams had proposed that the null-subject parameter took awhile to learn, and Yang (2002) attempts to explain this as the result of the trail-and-error learning model. But as we discussed (see the data in (21) and the pages following it), the evidence is strong and accepted in the developmental psycholinguistic field that very young children have the correct value of this parameter.
- 61.
- 62.
Charles Yang (pc) writes, “We cite Yang 2002, which does discuss the example further, and does do the calculations. These calculations demonstrate that the age of learning of V to I is correctly predicted by the model.” I have searched Yang (2002) and can’t find any calculations for the learning of V to I via the variational learning model. On p. 103, Yang says that verbs preceding negation or adverbs are signatures (i.e. unambiguously, independent of all other parameters), which we have already argued they are not. He calculates on that page that sentences with verbs preceding negation or adverbs make up about 7% of the input to the French-learning child, and thus takes 7% as an empirically-derived bound on how much of such input is necessary But there is no calculation of how the Verb to I (Tense) parameter is learned, here or elsewhere in the book, so far as I can find. Even if we don’t add other parameters, and thus leave the relevant sentences as “signatures” in this very restricted (one parameter) context, the point I’ve made in the main text holds. Namely, learning of V to I should be very slow, since whenever the child selects a 0 (no) value for V to I for the grammar on a trial (which should happen fairly often), and thus correctly parses (up to the other parameters, if they’re relevant) an input sentence (93% of input sentences), the 1 (yes) value of the V to I parameter will be punished. I see no calculations in Yang (2002) that show that this is wrong.
- 63.
The variational learning theory would also have comparable problems explaining why V to C (for finite verbs) wouldn’t also suffer from being presented with many ambiguous sentences. Consider, for example, an SVO sentence in Swedish or another mainland V2 Scandinavian language. This could be analyzed without verb movement, since the underlying word order is SVO. In fact, there seem to be counts of productions showing that the speakers of the language produce mostly SVO sentences (Wexler 1993, following p.c. from David Lightfoot). Shouldn’t this slow down the setting of the + V2 value? Yet we know (Wexler 1994 and many subsequent publications in the OI literature) that this value is set very early, with almost no errors. Yang (2002 in fact argues that the V2 parameter is not correctly set at an early age. He points out (section 4.1.2) that many early utterances in one Dutch child are “V1”, that is, the first word is the verb. He concludes from this that the child has not learned the V2 setting; rather, that V2 is competing somehow with a setting that would characterize Hebrew. But there is no reason to think that in fact the child hasn’t learned that V moves to C. As pointed out in footnote 13, it is well known that Dutch shows topic-drop. If a DP is sufficiently prominent in the discourse and is in Spec, CP, then it may be omitted. It is an open empirical question whether children in the OI stage drop topics more than adults do (which wouldn’t be surprising on independent grounds). Note that two of the examples that Yang cites (p. 106) provide evidence for the Topic-Drop view, since objects seem to be missing from sentences with transitive verbs (thus the direct object would be missing). These include the Dutch equivalents of know I not (something like that missing from Spec, CP) and see I yet not (the object of see appears to be missing, presumably from Spec, CP). The other two examples (shines the sun and can I not run) do not appear to be missing direct objects (on the common reading of run), but could easily be omitting some kind of adverbial. It would be very good to have an empirical study that determined how many of the V1 sentences could be interpreted with a fairly obvious missing element in Spec, CP. If such an analysis exists, I don’t know it. At any rate, Dutch linguists have felt quite comfortable in interpreting these sentences as showing a Dutch-like ability to drop an element in Spec, CP under certain pragmatic conditions. Furthermore, and importantly, independent of the V1/V2 discussion, the major point made at the beginning of this footnote holds. The finiteness/word order correlation (even with V1/V final) can’t hold in the variational learning model because when the child hears an SVO sentence, and has selected a value of no verb raising at all (e.g. something like an English value), this setting will have its weight added to. Just as Legate and Yang argue that ambiguous data leads to the OI stage, the 70% or so SVO data that a child hears in an SVO language should lead to a long period of producing sentences with objects, adverbs, etc. raised to Spec, CP (topicalized) followed by the subject followed by the finite verb, that is XP NP (subject) V pattern. We know that these hardly exist (Poeppel and Wexler 1993; Santelmann 1995 among many others). See (7) for example, where many of the 1st position NP’s won’t be subjects). Furthermore, since this V2 Scandinavian language will be OI for children, the model we are discussing says that the kids think that the finite (for adult) verb forms don’t show tense, that is, the languages are –Tense. Presumably this means that the finite verbs (which the kids will take to be not marked by tense) will not be able to raise to V2 (this follows Legate and Yang’s ideas about the word order/finiteness correlation). Thus the prediction that verbs in this language can’t raise to C will be reinforced for young children. Finite verbs will have to stay in position, leading to many errors of production again, I know of no calculations of learning of V2 in this theory, but its properties don’t appear to satisfy the empirical constraints.
- 64.
In fact, on p. 338, the authors write, “…it would nevertheless commit us to the position that verbs do not undergo movement to Tense or similar functional nodes in [−Tense] grammars such as Chinese – which at least one of us not comfortable with.” Given this consideration, it would seem that it may be only a question of how each verb is spelled out (given the inflectional features that drive movement) that is under consideration. Why then, is there a “parameter” of + or – Tense? Everytime there is variation, it doesn’t mean a “parameter” has to be learned. Rather, there might be a lexicon that has to be learned. E.g., how to spell out features. It is possible that the fact that Chinese never spells out Tense, and English sometimes does is a parameter, but it would have to be argued for. What syntactic phenomena follow from the proposal?
- 65.
The authors (p.c. to Jill de Villiers) say that they prefer the second possibility, which we will soon discuss.
- 66.
We’ll ignore the fact that there are languages (e.g. Italian, Icelandic) in which infinitives raise.
- 67.
Furthermore, suppose that the child selects the + Tense value while producing a sentence. That means that the structure contains Tense. What form should the child use on the verb? Why not the infinitival form? After all, the child may consider the infinitival form (with an infinitival suffix) as “ambiguous” for tense marking. What in the theory says that this won’t happen? I don’t see any consideration, since the theory of ambiguity seems to only say that a verb is ambiguous if and only if there is no suffixal marking on it. Since the infinitive has such an inflection, it should sometimes raise (as often as finite verbs?), again strongly contrary to fact.
- 68.
I assume that they mean a lack of tense marking. They say, “rewards” [−Tense.]
- 69.
Legate and Yang must be aware that their explanation of this central, strong empirical result is not parametric, but rather statistical and independent of the parameter system, because they choose to give it a different explanation than their parametric explanations. In other words, Verb to Tense is not learned as a parameter value in their system, at least not during the OI stage. Of course, we have seen in the text that the parametric explanation predicts the data correctly and their statistical explanation doesn’t.
- 70.
It might even be said that the genetics of development of OI’s has made more progress (though only a bit) so far, than the genetics of UG, and might be an avenue to help us discover the genetics of UG. For example, if we find the gene(s) (on chromosome 19q? (Falcaro et al. (2008)) that are responsible for the existence or withering away of UCC, we might have a link to genes that help to specify how syntactic feature-checking mechanisms work. Just speculation for now, but we can’t take the lack of of a biological mechanism for UG to be an argument against its existence. Ditto for maturation.
- 71.
One might also point out that we have no knowledge of the biological mechanism for learning, so that UG, maturation, learning are all equal on this score. Failing any physical evidence, we must go with the best computational level explanation, which is what linguistics and psycholinguistics do as standard business.
- 72.
Of course, not just forms of be are omitted. Other auxiliaries are omitted also. In English, the major other auxiliary is have, used in the perfect. Since English-speaking young children (especially American children as opposed to British) hardly use the perfect during the age-range of the OI-stage, we don’t have much of a chance to observe have omission. However, have omission is broadly seen in other languages, where the perfect is used as the simple past, for example, German. There has been discussion of modal omission also, although to my knowledge, strong and clear quantitative results on this topic aren’t available.
- 73.
The few examples of forms like (30b) that are observed are forms where be is clearly a kind of main verb, not an auxiliary, sometimes meaning something like act like, as in, You be Superman and I be Batman, meaning, you act as Superman and I’ll act as Batman. It doesn’t mean You are Superman and I am Batman. Also, some readers might relate (30b) to forms that occur in some varieties of African American English. But the meanings would be quite different. (30b) in AAE relates to particular relations between tense and aspect; the form might look the same, but it’s not an example of an OI.
- 74.
- 75.
Small clauses like I made him leave are called “small” because they are assumed to have no inflectional functional categories, in particular no Tense category. Since Tense does not exist, there is no V Requirement in small clauses. Thus be is not required in small clauses; therefore, it doesn’t exist in small clauses.
- 76.
Schutze points out that there might be cases where Tense is omitted in the embedded clause, and thus be could be omitted. E.g. in John will be late (the “target structure”), the child might omit Tense, and thus no will and no be would be inserted, and John late would surface. It would be hard to know from CHILDES data, however, if that were the proper analysis of these structures – they might arise from e.g. John is late. Thus the best cases are the ones Schutze studies, where there is the surface existence of Tense indicated by the modal, or by the existence of to. An elicitation study, though difficult, might provide data, that is, an elicitation of sentences where the most natural form would be something like John will be late. If the child provides John late to such an elicitation, it would confirm that Tense omission and be omission were going on.
- 77.
Schutze considers a potentially more fundamental way of deriving the cross-linguistic differences; the parameter has to do with how event variables are bound. This shouldn’t make a difference in the argument here, except that there might even potentially be more evidence available to the learner about which value of the parameter is correct. The suggestions I have made here should be fairly easy and formal for the learner; thus they may be the way the parameter is set even if it relates to the binding of event variables.
- 78.
Assuming either that all languages have Tense in root structures, or assuming that Arabic has Tense in predicative structures because it has tense in other (verbal) structures.
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Wexler, K. (2011). Grammatical Computation in the Optional Infinitive Stage. In: de Villiers, J., Roeper, T. (eds) Handbook of Generative Approaches to Language Acquisition. Studies in Theoretical Psycholinguistics, vol 41. Springer, Dordrecht. https://doi.org/10.1007/978-94-007-1688-9_3
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