These are excerpts and elaborations from my book "The Nature of Consciousness"
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The Script In the 1970s, Roger Schank employed similar ideas in his
model of conceptual dependency and in his theory of "case-based
reasoning. Case-based reasoning is a
form of analogical reasoning in which the elementary unit is the case, or
situation. A type of memory called episodic archives generalizations of all
known cases. Whenever a new case occurs, similar cases are retrieved from
episodic memory. Then two things happen. First, the new case is interpreted
based on any similar cases that were found in the episodic memory. Second, the
new case is used, in turn, to further refine the generalizations, which are
then stored again in episodic memory. The crucial features of this
model are similar to the ones that characterize frames. Interpretation of the
new case is expectation-driven, based on what happened in previous cases. Episodic memory contains examples of
solutions, rather than solutions or rules to find solutions. Because the episodic memory
is continuously refined, Schank refers to it more generally as
dynamic memory: it can grow on its own, based on experience. The script is an extension of the idea of
the case. A scene is a general
description of a setting and of a goal in that setting. A script is a particular instantiation of a
scene (many scripts can be attached to one scene). 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. For example, a script
describes the scene of a restaurant: the host seats the customers as they walk
in and hands them a menu, the waiter takes their order and delivers it to the
kitchen, the waiter brings the food, the waiter brings the bill, the waiter
brings the change. When we enter a restaurant, we know what to expect. The
moment we recognize a building as a restaurant, we know that there are waiters
inside. If we walk in, we expect to be handed a menu, and we expect a waiter
to take our order, and at the end we expect the bill. This is all in the script
for restaurants. Our daily life is controlled by a multitude of scripts that
direct our actions in all stereotypical situations (the vast majority of the
situations that we encounter in our life). 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. Such new 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. Here, again, remembering is
closely related to understanding and learning. Memory has the passive function
of remembering and the active function of predicting. The comprehension of the world and its categorization proceed
together. More and more complex
structures were added by Schank and his associates to the basic
model of scripts. A "memory organization packet" (MOP) is a structure
that keeps information about how memories are linked in frequently occurring
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.
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 underlying
stories 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. This may explain both the
passion for sport races (whether car racing or cycling) and for narrative art
(whether films or novels). Both categories of human activities basically
construct very complicated stories that challenge our minds. As we follow a
race, we construct a story based on the stereotype actions that can happen in a
race. And we root for our idol based on what stereotype actions would propel
her/him to the head of the race. As we watch a film, we construct a story based
on the stereotype actions that can happen in a film. And we identify with the
protagonist based on what stereotype actions would make her/him succeed. Back to the beginning of the chapter "Cognition: A General Property of Matter " | Back to the index of all chapters |
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