Roger Schank:

Several books

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A number of primitive actions can be used to form all complex actions. Each action entails roles which are common to all languages. Therefore a verb can be represented in terms of more primitive concepts. Schanks' "conceptual dipendency" draws ideas from Fillmore and Katz.
Conceptual dependency parsing reveals things that are not explicit in the surface form of the utterance: additional roles and additional relations. They are filled in throught the system's knowledge of lexical semantics and domain heuristics that help infer what is true in the domain. 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.


A script is a social variant of Minsky's frame. A script represents stereotypical knowledge of situations as a sequence of actions and a set of roles. Once the situation is recognized, the script prescribes the actions that are sensible and the roles that are likely to be played. The script helps understand the situation and predicts what will happen. A script performs anticipatory reasoning.
Scripts originate as units in the "event memory". The comprehension of an event contributes to reorganize the abstractions of past events so that their scripts be more and more efficient in recognizing that type of event. This type of gradual learning depends on similarities between events. From the similarities scripts and roles are abstracted.
Memory is syntactic (episodic) and dymanic (adaptive). Memory has the passive function of remembering and the active function of predicting. The comprehension of the world and its categorization proceed together.

DYNAMIC MEMORY (Cambridge Univ Press, 1982)

Dynamic memory is a type of memory that can grow of its own, based on experience. A script is a generalization of a class of situations. If a situation falls into the context of a script, then an expectation is created by the script, based on what happened in all previous situations. If the expectation fails to materialize, then a new memory must be created. This memory is structured according to an "explanation" of the failure. Generalizations are created from two identical expectation failures. Memories are driven by expectation failures, by the attempt to explain each failure and learning from that experience. New experiences are stored only if they fail to conform to the expectations. Remembering is closely related to understanding and learning.
A scene is a general description of a setting and a goal in that setting. A script is a particular instantiation of a scene (many scripts can be attached to one scene). A "memory organization packet" is a structure that keeps information about how memories are linked in frequently occuring combinations. A MOP is both a storing structure and a processing structure. A MOP is basically an ordered set of scenes directed towards a goal. A MOP is more general than a script in that it can contain information about many settings (including many scripts). A "thematic organization packet" is an even higher-level structure that stores information independent of any setting.

Schank Roger: TELL ME A STORY (Scribner, 1990)

Ultimately, knowledge (and intelligence itself) is stories. Cognitive skills emerge from discourse-related functions: conversation is reminding and storytelling is understanding (and in particular generalizing). The stories that are told differ from the stories that are in memory: in the process of being told, a story undergoes changes to reflect the intentions of the speaker. The mechanism is similar to script-driven reasoning: understanding a story entails finding a story in memory that matches the new story and enhancing the old story with details from the new one. Underlying the mechanism is a process of "indexing" based on identifying five factors: theme, goal, plan, result and lesson. Memory actually contains only "gists" of stories, that can be turned into stories by a number of operations (distillation, combination, elaboration, creation, captioning, adaptation). Knowledge is embodied in stories and cognition is carried out in terms of stories that are already known.

THE COGNITIVE COMPUTER (Addison-Wesley, 1984)

An accessible introduction to Schank's theory of natural language understanding, conceptual dependency, scripts, and some of the early programs of his school (MARGIE, SAM, POLITICS, FRUMP, IPP, BORIS, CYRUS).

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