4.4.3 ``Special'' Words

Exceptions for the treatment of determiners and negation.

1. First, look at the following lexicon/4 facts for determiners:

   lexicon(det,_,[every],uni).

   lexicon(det,_,[a],indef).

   Note that these entries contain no semantic information whatsoever. This is because the semantic contribution of determiners is not simply a constant or predicate symbol, but rather a relatively complex expression that is expressed differently in different formalisms. Hence we shall specify the semantics of these categories in the semantic macros alone.

2. Secondly, a small number of important words - in particular, copula and the verb phrase modifier construct ``does not'' - are not listed in the lexicon at all. This is because they are not associated with either a relation symbol or a constant, and there's no additional information we would like to list for them. For such words, a lexicon/4 fact would simply list the word form as Phrase entry. Instead, we will check their word form directly in our lexical rules (or as one also says: we treat them syncategorematically ). For example, the following rule handles verb phrase negation:

   neg(Neg)--> [not], {modSem(neg,Neg)}.

   Thus here the semantic macros will again be the sole source of semantic information.

There are two classes of words that get a special treatment in our framework:

1. First, look at the following lexicon/4 facts for determiners:

   lexicon(det,_,[every],uni).

   lexicon(det,_,[a],indef).

   Note that these entries contain no semantic information whatsoever. This is because the semantic contribution of determiners is not simply a constant or predicate symbol, but rather a relatively complex expression that is expressed differently in different formalisms. Hence we shall specify the semantics of these categories in the semantic macros alone.

2. Secondly, a small number of important words - in particular, copula and the verb phrase modifier construct ``does not'' - are not listed in the lexicon at all. This is because they are not associated with either a relation symbol or a constant, and there's no additional information we would like to list for them. For such words, a lexicon/4 fact would simply list the word form as Phrase entry. Instead, we will check their word form directly in our lexical rules (or as one also says: we treat them syncategorematically ). For example, the following rule handles verb phrase negation:

   neg(Neg)--> [not], {modSem(neg,Neg)}.

   Thus here the semantic macros will again be the sole source of semantic information.

In Exercise 4.1, you are asked to find out how copula constructions are handled in our approach.