Piero Scaruffi

These are excerpts and elaborations from my book "The Nature of Consciousness"

Conceptual Dependency The culmination of this school was, in the 1970s, Roger Schank's "conceptual dependency" theory (1969), whose tenet is that two sentences whose meaning is equivalent must have the same representation. This goal can be achieved by decomposing verbs into elementary concepts (or semantic primitives). �Sentences describe things that happen, i.e. actions. While every language provides for many different actions (usually expressed as verbs), it turns out that most of them can be defined in terms of simpler ones. For example, �to deliver� is a combination of �to move� and other simpler actions. In other words, a number of primitive actions can be used to form all complex actions. In analyzing language, one can therefore focus on those primitive actions. Or, equivalently, a verb can be decomposed in terms of more primitive concepts.� Each action entails roles which are common to all languages. For example, �to move� requires an agent who causes the move to happen, an object to be moved, an old location and a new location, possibly a timeframe, etc. Sometimes the roles are not explicitly stated in a sentence, but they can be derived from the context. Whether they are stated in the sentence or implicit in the context, those roles always exist. And they exist for every language that has that concept. �To move� may be translated with different words in different languages, but it always requires a mover, an object, etc.� An important corollary is that any two sentences that share the same meaning will have exactly the same representation in conceptual dependency, regardless of how much is left implicit by each one, regardless of how each is structured. If they refer to the same mover and the same object and the same location and the same timeframe, two different sentences on �moving� will have identical representations. Conceptual dependency reveals things that are not explicit in the surface form of the utterance: additional roles and additional relations.� They are filled in through one�s knowledge of lexical semantics and domain heuristics. These two components help infer what is true in the domain. Conceptual dependency represented a major departure from �Chomskyan� analysis, which always remained relatively� faithful to the way a sentence is structured. Schank�s analysis considers negligible the way words have been assembled and shifts the emphasis on what is being described. If nothing else, this is presumably closer to the way our memory remembers them.   Back to the beginning of the chapter "Language: Minds Speak" | Back to the index of all chapters