1.2.1 The Lexicon

1.2.3 Morphological criteria for determining category

This is not an unusual situation and neither is it particularly problematic. Clearly, the word weather can function as either a noun or a verb. As a noun it can take the plural morpheme and as a verb it can take the present tense morpheme. There may be issues here to do with how we handle this situation: are there two entries in the lexicon for these cases, one for the noun weather and one for the verb, or is there one entry which can be categorised as either a noun or a verb? Again, however, we will not concern ourselves with these issues as they have little bearing on syntactic issues.

1.2.4 Distribution

Let us turn now to the observations made in (2) and (3). There we observed that there are certain positions in a sentence that some words can occupy and other words cannot. Clearly, this is determined by category. This is perhaps the most basic point of word categories as far as syntax is concerned. The grammar of a language determines how we construct the expressions of the language. The grammar, however, does not refer to the individual words of the lexicon, telling us, for example, that the word cat goes in position X in expression Y. Such a system would not be able to produce an indefinite number of sentences as there would have to be such a rule for every expression of the language. Instead, the grammar defines the set of possible positions for word categories, hence allowing the construction of numerous expressions from a small number of grammatical principles. The question of how these positions are defined is mostly what this book is about, but for now, for illustrative purposes only, let us pretend that English has a rule that says that a sentence can be formed by putting a noun in front of a verb. This rule then tells us that the expressions in (15) are grammatical and those in (16) are not:

1.3.4.3 Adjectives

There is some debate about the status of this morpheme which revolves around the central issue of our present discussion. On the one hand, ‑ly might be taken as a derivational morpheme which is applied to a lexical item of one category to derive another lexical item of another category. This would be similar to morphemes such as ‑er in cook‑er, ‑ic as in scen(e)‑ic or ‑ment in govern‑ment. We have not been concerned with such morphemes so far as they tend to be rather restricted, applying to certain lexical items of a given category rather than to the category as a whole. There are, for example, no forms *exister (someone who exists), *viewic (the property of resembling a nice view) or *rulement (the collective body of people who rule). As we have been concerned in using morphological observations for identifying categories, the derivational morphemes would have been only of limited use to us. The important point about derivational morphology is that it takes place in the lexicon, forming new lexical elements from others, prior to any grammatical operation. If ‑ly is a derivational morpheme, then adverbs are a different category from the adjectives they are derived from. However, we have no feature analysis for adverbs using the [±F], [±N] and [±V] features and as we have pointed out we cannot just introduce a new category into the system without there being some fairly substantial consequences. If we introduce a new feature to try to accommodate adverbs, we predict the existence of a further seven more categories for which we have very little evidence.

1.3.5.1 Inflections

One argument in support of this treatment of finite inflections concerns the difference between inflectional morphemes and derivational morphemes, discussed above. A derivational morpheme forms a new word from an existent one in the lexicon. This new word has lexical properties of its own and may even differ in its meaning from the original word. Furthermore, the process tends to be limited, applying to a selection of lexical elements rather than to whole classes. Inflectional morphology, on the other hand, does not change the lexical element, it just provides another form of that word. Often, it adds some element of meaning (such as tense or plural) to the meaning of the original word rather than changing the meaning to something else. This all suggests that the two processes are very different and that derivational morphology is something that goes on in the lexicon to expand the number of available words. Inflectional morphology is, on the other hand, too regular to be a lexical process, applying to whole categories. This would seem to be the hallmark of a syntactic process not a lexical one. We will assume therefore that verbal morphemes expressing tense and agreement are independent words inserted into a sentence in their own position and undergo a subsequent syntactic process which combines them with the verb that they are attached to.

1.3.5.1 Inflections

One argument in support of this treatment of finite inflections concerns the difference between inflectional morphemes and derivational morphemes, discussed above. A derivational morpheme forms a new word from an existent one in the lexicon. This new word has lexical properties of its own and may even differ in its meaning from the original word. Furthermore, the process tends to be limited, applying to a selection of lexical elements rather than to whole classes. Inflectional morphology, on the other hand, does not change the lexical element, it just provides another form of that word. Often, it adds some element of meaning (such as tense or plural) to the meaning of the original word rather than changing the meaning to something else. This all suggests that the two processes are very different and that derivational morphology is something that goes on in the lexicon to expand the number of available words. Inflectional morphology is, on the other hand, too regular to be a lexical process, applying to whole categories. This would seem to be the hallmark of a syntactic process not a lexical one. We will assume therefore that verbal morphemes expressing tense and agreement are independent words inserted into a sentence in their own position and undergo a subsequent syntactic process which combines them with the verb that they are attached to.

3.1.3 Heads and Complements

To see how categorial information gets into structure we must look more closely at heads and the notion of projection. We have seen how heads project their properties to the X' and thence to XP, the question we must ask therefore is where do heads get their properties from? The main point to realise is that the head is a word position and words are inserted into head positions from the lexicon. In chapter 1 we spent quite some time reviewing the lexical properties of words, including their categorial properties. These, we concluded, are specified for every lexical item in terms of categorial features ([±F, ±N, ±V]). If we now propose that a head’s categorial features are projected from the lexical element that occupies the head position we can see that phrases of different categories are the result of different lexical elements being inserted into head positions.

3.1.3 Heads and Complements

We then populate this structure by inserting words into it from the lexicon and these bring along with them their categorial features. Suppose we insert the verb fall into the head position, as this is categorised [–F, –N, +V] (i.e. verb) these will project to the head position:

3.1.3 Heads and Complements

In this way we can see that categorial features are actually projected into structures from the lexicon. This makes a lot of sense given that categorial properties are to a large extent idiosyncratic to the words involved in an expression and are not easily predicted without knowing what words a sentence is constructed from. Things which are predictable, such as that all phrases have heads which may be flanked by a specifier to its left and a complement to its right, are what are expressed by the X-bar rules. Thus we have a major split between idiosyncratic properties, which rightly belong in the lexicon, and general and predictable properties which rightly belong in the grammar.

3.1.6 Summary

Before moving on to look at other aspects of syntactic processes, let us consolidate what we have said in this section. X-bar theory is a theory of basic structure comprising of just three rules. These rules are generally applicable to all structures and substructures, no matter what their category: they are category neutral. The categorial status of a specific structure depends on the lexical elements it contains, in particular one word acts as the head of each phrase and this determines the category of the phrase by projecting its own categorial properties, established in the lexicon, to the X' node above it and ultimately to the XP.

3.2.2.1 D-structure and Theta Theory

We have now reviewed three simple and basic principles which regulate the assignment of Θ-roles within a structure: the Locality Condition on Theta-role Assignment, the UTAH and the Theta Criterion. All of these apply to D-structures, restricting the distribution of arguments at this level of representation. Collectively, the principles which govern Θ-role assignment are often referred to as Theta Theory and this can be considered as a part of the grammar, similar to the principles of X-bar theory which regulate the general formation of structures. A final important contributor to the well-formedness conditions of D-structure is the lexicon which provides structures with categorial information and Theta theory with the Θ-roles to be assigned. We might represent this in the following way:

3.2.3 Traces

3.2.3 Traces

What this means is that anything that is inserted into a structure from the lexicon cannot change from one level of representation to another. If a verb is put into a structure, nothing can delete or alter this verb, turning it into a noun, for example. Also no movement can alter a verb’s selectional properties: a transitive verb will remain transitive at D-structure and S-structure even if the object is moved.