9.2. Frames and schematic activation

As we have seen, the distinction between two different levels of competence is important from the point of view of interpretative processes; this distinction iden­tifies the set of interpretations conventionally associated with linguistic forms, and which constitute the object of study of lexical semantics. I would like now to analyze in more detail how the semantic-linguistic component contributes to comprehension processes. The schematic models discussed in the previous chapter are particularly suitable for this purpose.

As we saw, individual terms are connected to a scene, or standard context, of reference. For example, the Italian verb pranzare (which translates as "to (have) lunch") activates all the elements of the very general scene, "to eat," including those that cannot be directly subcategorized by that particular predicate. In the case of pranzare, the object of the action of eating cannot be lexicalized, because pranzare is an intransitive verb. It is not therefore possible to say:

3. * Oggi ho pranzato un polio. (* Today I lunched a chicken.)

However, each time the term to lunch is introduced into discourse, it activates the whole scene of "eating," of which lunch is a sub-specification relating to a particu­lar moment in the day, contrasting in this respect with to have dinner. Because the scene is inherently transitive, one of its constituent roles being an edible entity which is the object of the action, to lunch, inasmuch as it is part of the same scene, inherits what one could define as a conceptual ttansitivity. When inserted into a sentence, it activates even those roles that cannot be directly lexicalized. It is on the basis of this conceptual transitivity that in the sequence:

4. Ho pranzato volentieri. IIpolio era ottimo. (I was quite happy to have lunch. The chicken was excellent.)

we attribute the object role in our lunch to the chicken. At the level of under standing, this is very important, because it allows us to explain links of coherency and anaphoric connections between sentences. We have no difficulty in (4) in connecting the chicken to the object role activated by the frame "eating," and this explains why chicken can be introduced by the definite article. Normally the tied-

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nite article is used when referring to identifiable entities, typically entities that have already been mentioned in the discourse. However, even an entity that has not been mentioned can be referred to with the definite article if, as in our example, it has been implicitly introduced into the discourse through the activa­tion of a frame.

The relation between the meaning of an individual lexical entry and its un­derlying scene also explains why a sentence like (5) seems anomalous:

5. ? Aveva pranzato senza mangiare. (? He had had lunch without eating.)

To lunch necessarily implies "eating" in that it is part of the same scene. Cases like this are very frequent and can be explained adequately by a schematic semantic model able to give an account of the relation between the representation of lexical units and their textual insertion.

A great deal of attention has been devoted to this type of phenomenon in the field of artificial intelligence, which has traced the regularity of our comprehen­sion processes back to underlying schemata of knowledge: the structures for the representation of knowledge, for example frames, are composed of so-called slots that operate as default values, automatically activated in the absence of explicit indications to the contrary. In the by now famous example of the "restaurant" script,¹⁰ a series of slots describes the typical restaurant and its constituent ele­ments (waiters, tables, menu, etc.), together with the typical sequence of actions that occurs in restaurants (ordering, eating, paying, leaving, etc.). From a program that contains this script it is possible to infer that if someone enters a restaurant, orders, eats, and leaves, that person will probably also have paid, unless otherwise specified. Default values are activated, one might say, ceteris paribus. The concept of default values has been widely used to explain the contribution of lexical con­tent to textual comprehension.¹¹ It is undoubtedly very useful but it needs to be outlined more clearly.