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Figure 2.1 Government-binding theory However, the property [Glp] cannot disappear because of the existence of thousands of human languages. By hypothesis, principles of UG that solve this problem must be [alp], but they cannot solve the problem so narrowly as to pick out the same language for any data since there is more than one language; hence [lp]. Chomsky finds it ""surprising""-perhaps a ""defect"" in the scheme of evolution-that there is more than one language (Baker 2001; Chomsky 2000b). To account for multiplicity of languages, the P&P framework suggests the following compelling picture of language acquisition: ""We can think of the initial state of the faculty of language as a fixed network connected to a switchbox; the network is const.i.tuted of the principles of language, while the switches are the options to be determined by experience. Each particular human language is identified as a particular setting of switches"" (Chomsky 1997, part 1:6). These ideas were first articulated in the scheme of grammar known as Government-Binding Theory (figure 2.1).
2.3.
Government-Binding Theory Given the lexicon, the boldface levels represent the various structures generated by the computational system. Each of the surrounding principles 38
Chapter 2.
of UG mentioned in the boxes are language-independent, though as we will see, some of the ""principles"" (alternatively, ""modules"" of grammar) are subject to parametric variations. Move-a is the only transformational rule that converts phrase markers into phrase markers, where a could be any syntactic category. Such a rule will obviously overgenerate wildly.
Principles of UG work in tandem to constrain free movement-that is, any category can be moved anywhere provided no principle of UG is violated.
It is important to recognize that boldfaced levels of representations are ""events"" in the sense that they are theoretical constructs entirely identified in terms of what happens at each level. What happens is that certain principles of UG progressively interact with the lexicon to generate certain structures. For example, d-structure is identified because this is where, among other things, X-bar theory holds; s-structure is identified because this is where Case theory and Binding theory apply; and so on.
So if the course of theory requires some redesigning of the principles, then the nature of interactions and hence the character of a level will change. In principle if nothing happens at a level, then the level does not exist.
However, there is a distinction between the ""inner"" levels of d-structure and s-structure and the ""outer"" levels of PF and LF. What happens at PF and LF is that, apart from the application of various principles as in the ""inner"" levels, they interact with nonlinguistic components of the mind.
Hence, in that sense, they must exist regardless of the course of the theory as long as the general organization depicted in figure 2.1 holds: PF and LF are theoretically indispensable since they are the interface levels of language. In other words, PF and LF are ""conceptually necessary"" while d-structure and s-structure, to which no other component of mind has access, are mere constructs of theory. This among other things led Chomsky (1993) to eliminate the intermediate levels in the Minimalist Program.
Obviously, what used to ""happen"" at these levels now happens elsewhere, if at all, as we will see in chapter 5.
The phenomenon of displacement, we saw, quite literally requires that elements be moved from one structure to form other structures geared to proper interpretation(s), the sense of proper varying with the nature of constructions. For example, scope distinctions typically require that elements be moved such that dierent semantic interpretations are generated; pa.s.sivization requires, on the other hand, that elements are so moved and introduced that semantic interpretation remains unchanged.
Therefore, we need to identify an initial form on which movement Linguistic Theory I
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takes place, and another form that results from the movement. We will see that semantic interpretation will require a further-LF-level of representation.
2.3.1.
D-Structure How are the initial forms-d-structures-generated? It is natural to think of d-structures as generated from a system of rewriting rules called ""phrase-structure rules,"" a sample of which is presented in (16).4 The fact that this rule system was essentially eliminated in favor of deeper principles over a quarter of a century ago is not yet fully recognized outside linguistics circles. Hence it will be worthwhile to spend some time on this development to appreciate one significant point of departure for the P&P framework.
(16) a. S ) NP VP b. VP ) V NP c. NP ) DET N d. NP ) N Rules in (16) will a.n.a.lyze a sentence (S) down to the basic syntactic categories (V, N, DET), at which point lexical items may be suitably ""inserted"" to generate an initial (phrase-marker) representation. For example, the sentence Bill read the book has a structure that may be displayed either as a labeled bracketing (17) or, equivalently, as a tree diagram (170). Note that the first line in (17) represents a sample of rules of lexical insertion for either diagram.
(17) N ) Bill, book; V ) read; DET ) the [S [NP [N Bill]] [VP [V read] [NP [DET the] [N book]]]]
(170).
Since there is a finite enumeration of lexical items, the rule system (16) will generate only a finite number of ""structure descriptions"" (expressions) 40
Chapter 2.
such as (17) or (170). The system can be given infinite capacity by adding a recursive clause (18c) and modifying rules (16c) and (16d) accordingly as in (18a) and (18b).
(18) a. NP ) DET N0 b. N0 ) N c. N0 ) N S With proper addition of lexical items, this system will now have infinite generative capacity. For example, with the addition of lexical items belief and that, the rule system will generate a structure description for the belief that Bill read the book. With a few more additions to the lexicon, this system will generate sentences such as John"s finding that the belief that Bill read the book surprised Tom interested Harry.5 The system will also be adequate in the sense that it can be used to represent all and only (d-structure) expressions of English.
The system of phrase-structure rules specifies the configuration-that is, the order-in which lexical items appear in syntax. Roughly, only those lexical items may be inserted via the rules of insertion for which predetermined positions are available in the structure. For example, the expression *Bill read the book the boy will be rejected since the extra element the boy cannot be inserted in the configuration. Thus both the number and the order of the const.i.tuents are exactly determined. If the phrase structure system needs to be given up on independent grounds, these properties will have to be expressed by alternative means.
There are a variety of problems with this rule system. I will briefly discuss a few of them (Chomsky 1972c; 1986, 5664, 8082, for more). Notice that the discussion here is restricted to whether phrase-structure rules are needed for d-structure representation. The wider issue of whether this system alone is adequate for syntactic description of languages is discussed in Chomsky 1957 with the conclusion that a transformational component is also needed. I take this conclusion for granted.
2.3.1.1.
C-Selection The system plainly has an ad hoc, taxonomic character in the sense that it is basically a list of categorial relationships of a preliminary sort. For example, the book is a part of speech consisting of two subparts the and book in that order. Rule (16c) simply states this observation in categorial terms. Thus the system, though observationally correct, is likely to have missed underlying uniformities and generalizations. Two of these underlying uniformities, among others, deserve imme- Linguistic Theory I
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diate mention. First, the lexicon, which the child has to acquire in any case, is richly structured (Chomsky 1965, 164170). Each lexical item has three categories of information in a full dictionary: phonetic (how it is p.r.o.nounced), semantic (what it means), and categorial or syntactic (how it is structurally characterized). Boy, for example, is categorially characterized as a noun; it has a certain sound; and it has semantic features such as animate, human, male, and so on.
More to the point, verbs and other basic categories carry categorial information regarding their C-selection (""C"" stands for categorial); alternatively, basic categories carry information about what they subcategorize for. Apart from verbs, other basic categories such as nouns, adjectives, and prepositions also C-select: the destruction of the city, angry at Sam, out of the room, and so forth (Jackendo 1983, 5960).
Keeping to verbs, consider the verb read. On acquiring the verb the child knows that it has the structure ""x(read )y"" whereas die has the structure ""x(die)""-that is, read is transitive and die intransitive. However, the child also knows that transitivity comes in dierent forms. Notice the variety of things that follow the main verb in the following examples: read a book (NP), made me angry (NP, AP), went out of the room (PP), paid handsomely (AdvP), gave an apple to the boy (NP, PP), thinks that John is sick (Finite Clause), told Mary that John is sick (NP, Finite Clause), and persuaded Mary to visit John (NP, Infinitival Clause).
These facts allow us to say that, for example, read C-selects an NP, persuade C-selects an NP and an infinitival clause, and so on. This the child already knows. Notice also that all of the examples listed above are VPs such that we get full sentences if we attach a Subject-say, Jones (NP)-in front of them. So, in eect, in learning a verb, the child has learned the categorial information encoded in a VP involving that verb. Let us say a verb phrase has two major parts: a head and a complement. The head of a phrase is the most prominent element of the phrase in the sense that the head is what the phrase essentially is: the old man is a man, read a book is a reading, told Mary that John is sick is a telling. A complement is what the head C-selects. So various head-complement relationships that const.i.tute VPs are listed, among other things, in the verbal part of the lexicon.
To that extent, the phrase-structure rule (16b) [VP ) V NP], for example, is redundant. However, unlike the rule, C-selection does not specify the direction in which the complement NP is to be found.
Moreover, there are uniformities in the head-complement relationships across categories that phrase-structure rules miss. Generalizing from the 42
Chapter 2.
VP case, we can say that a noun phrase (NP) consists of a head noun followed by a complement. Now, notice the striking similarities between (19), (20), and (21).
(19) Bill [VP observed [S that Jamie was still awake]]
(20) the [N0 observation [S that Jamie was still awake]]
(21) Bill"s [N0 observation [S that Jamie was still awake]]
Similar structures can be obtained for pairs such as claimed/claim, construct/construction, and the like. The noun observation that heads the structure [observation [S that Jamie was still awake]]-and that is the nominal form of the verb observe-has the same complement as the verbal head in (19). So the property of C-selecting a (finite) clausal complement really belongs to the word observe and its derivatives such that the forms (19)(21) are largely predictable from lexical information alone. This generalization across phrasal categories is missed in the relevant phrase-structure rules. Also notice that (20) and (21) are NPs according to the phrase-structure rule (16c) read with (18e): (NP ) DET N0 S). Hence, this rule is redundant as well insofar as it conveys categorial organization of NPs.
Now if we simply adopt a global principle that links lexical information to syntactic const.i.tuency, then phrase-structure rules are not needed to that extent. This is achieved by the Projection Principle: (22) Lexical structure must be fully represented categorially at every syntactic level.
The principle enables us to view syntactic structures as ""projections""
from the lexicon. The structures (20) and (21) have other related interests.
The value of DET in (20) is the definite article the while in (21) it is John"s, a full noun phrase (Chomsky 1986). It also appears in structures such as (23) [NP John"s [VP hitting the ball]]
where it occurs to the front of a VP rather than an N0 as in (21). This suggests that DET belongs to a category more abstract than the standard category of articles and that the category is available across phrases. Let us call this category ""Specifier"" (Spec), which in English occurs at the front of a phrase. Then both (21) and (23) have the structure [Spec [XP . . . ]], where ""XP"" is either an N0 or VP. The sequence Spec-head-complement then fully captures the categorial information of phrases such as (20), (21), and (23). Extending the idea, the element very in very Linguistic Theory I
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confident of his ideas may now be viewed as the Spec of an adjectival phrase headed by the adjective confident.
2.3.1.2.
X-Bar Theory These ideas can be explored further. Let us think of two basic category features ""N(ominal)"" and ""V(erbal)"" each of which has binary (G) options. This will generate four phrasal heads as in (24); the traditional categories of noun, verb, and the like are no longer basic syntactic categories, but are mnemonics for a collection of syntactic features.
(24) N, aV : N(oun) aN, V : V(erb) aN, aV : P(reposition) N, V : A(djective) The heads N, V, P, and A project four categories of phrases, namely, NP, VP, PP, and AP. Each of these will obey the general scheme Spec-head-complement suggested above. Further, it has been a discovery of some importance that various generalizations can be captured if the scheme has the following general pattern called ""X-bar theory"" (figure 2.2).
The important point to note is that a head X projects a category X-bar consisting of X and its complement, while a further projection of X belongs to the category X-bar-bar ( XP, a phrase) consisting of the specifier and X-bar; hence, the Spec belongs to a level ""higher"" than the level of X and its complement. This hierarchy is of much use in defining various structural relationships between categories. For example, lexical information regarding C-selection simply says that a verb C-selects, say, an NP. It does not explicitly say which NP is C-selected, though there is Figure 2.2 X-bar organization
44.
Chapter 2.
Figure 2.3 Clause structure an implicit suggestion that only that NP counts that is ""related"" to the verb somehow-the one that falls within the ""domain"" of the verb. How is this suggestion structurally realized? We may now use X-bar-theoretic notions to bring it out explicitly. For two mutually exclusive elements a and b, let us say ""a c-commands b"" just in case every maximal projection dominating a dominates b. We say that an element a ""governs"" an element b just in case a and b c-command each other and a is a head-that is, a A fN, V, A, P, Inflg. I explain Infl in a moment; for now, let us just concentrate on structural relations.
Thus, in figure 2.3, Infl c-commands V; V does not c-command either Infl or [NP, S], though V c-commands [NP, VP], which c-commands V as well. Therefore, Infl does not govern V but V governs [NP, VP]; [NP, VP]
does not govern V since the former is not a head. It is clear, then, that C-selection is satisfied under government (see Duarte 1991 for more). Recall that phrase-structure rules conveyed two sorts of information: categorial and configurational, namely, the nature and the order of the const.i.tuents.
We saw above that the categorial part is captured in the lexicon. Capturing the configurational part is a complex problem. X-bar theory now may be viewed as solving part of this problem. The rest of the ordering, as we will see, will be accomplished by other ""modules"" of grammar-for example, Case theory.
Notice that X-bar theory is language-independent though it is a.s.sociated with a few (probably, just two) options: the scheme could be left-ordered, head-first as above for languages such as English and French, or, it could be right-ordered, head-final, as in j.a.panese. The interesting Linguistic Theory I
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fact is that all categories of phrases in a given language (typically) obey identical orientation. Children can fix the value of the orientation parameter for their language from very simple data such as drink milk. Thus, for English, C-selection in combination with X-bar theory now requires that the complement(s) be located to the right of the head. The X-bar scheme can be easily generalized to sentences and clauses (figure 2.3).
I have so far considered ""proper"" heads: N, V, A, and P. Verbal forms typically contain various kinds of information regarding tense, modality, aspect, and agreement. Depending on the language, some or all of this information is morphologically realized. Let us collectively call these elements ""Infl"" (for ""inflection""). I will use Infl to represent just the tense information.
The tense part of a verbal form is interesting in that it does not really modify the ""basic"" meaning of the verb. In some sense, ate means the same as will eat insofar as the action is concerned, but of course the timing of this action, past and future respectively, varies. In that sense, the tense information is detachable from the verb itself: Tense V. It also stands to reason that this information is really related to how the whole sentence is to be interpreted. Thus, the dierence between John ate a cake and John will eat a cake relates only to the dierence in the timing of the event John"s-eating-a-cake. The tense information, therefore, is central in distinguishing between these two sentences. By parity, the infinitival to is also central in the same sense since it suppresses timing information in the clause in which it occurs.
On these considerations, the tense inflection Infl can be thought of as heading the sentence, where the sentence itself is the maximal projection of this head, Infl-bar-bar. The intermediate projection Infl-bar will establish the sisterhood between Infl and the complement VP. Thus, all requirements of the X-bar format are met (for more, see Jackendo 2002, 6.2.2). Furthermore, cla.s.sical notions of Subject and Object, which play crucial roles in the syntactic description of languages (Chomsky 1965), can also be explicitly defined within the X-bar format. Subject is the NP immediately dominated by S-that is, [NP, S]. Object of the main verb is the NP immediately dominated by VP-that is, [NP, VP]. Following exactly the same line of reasoning and generalizing further, we postulate a sentence-external category Comp (for ""complementizer""), which in English may be that, for, or null.
Thus a clause, finite or infinitival, has the following structure: (25) [S-bar Comp [S NP [Infl-bar Infl [VP V . . . ]]]]