And here is a lovely explanation of the
issue, from the following paper:
http://www.sciencedirect.com/science/article/pii/0010028575900249
:
Although it is always
possible for an ingenious philosopher or psychologist to invent criteria1
attributes defining a category, earlier research has shown that actual subjects
rate superordinate semantic categories as having few, if any, attributes common
to all members (Rosch et al., in press). Thus, if the “categorical”
nature of these categories is to be explained, it appeared most likely to
reside in family resemblances between members. Part of the purpose of the
present experiment was to obtain portraits of the distribution of attributes of
members of a number of superordinate natural language categories. Part of the
hypothesis was that category members would prove to bear a family resemblance relationship
to each other. The major purpose of the experiment, however, was to observe the
relation between degree of relatedness between members of the category and the
rated prototypicality of those members. The specific hypothesis was that a
measure of the degree to which an item bore a family resemblance to other
members of the category would prove significantly correlated with previously
obtained prototypicality ratings of the members of the category.
Sincerely,
Rich Cooper
EnglishLogicKernel.com
Rich AT EnglishLogicKernel DOT com
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From: ontolog-forum-bounces@xxxxxxxxxxxxxxxx [mailto:ontolog-forum-bounces@xxxxxxxxxxxxxxxx]
On Behalf Of Rich Cooper
Sent: Tuesday, November 19, 2013
5:28 PM
To: '[ontolog-forum]
'
Subject: [ontolog-forum]
Semantic Dementia
Dear Ontologers,
I found an article on sciencedirec.comt
that relates to experimental evidence on how people form categories, and how
they associate multiple attributes to categories. This is a quote from
the abstract of the article:
“Patients learned to assign abstract visual stimuli to two
categories. The categories conformed to a family resemblance structure in which
no individual stimulus features were fully diagnostic; thus the task required
participants to form representations that integrate multiple features into a
single concept. Patients were unable to do this, instead responding only on the
basis of individual features.”
They called the condition of these
patients “semantic dementia” because the patients lost the ability
to consider multiple alternative representations simultaneously. The
article is at:
http://www.sciencedirect.com/science/article/pii/S0010945213002517
They describe a structural theory which
they call a “spoke and hub” structure in the affected brain area
(ALT) where each spoke is one sensory modality that gets integrated at the
hub.
The way they describe the deficit sounds
to me that the loss was in deduction, specifically in integrating each of the
spokes into a coherent response based on all the spokes.
When concepts had multiple spokes,
(attributes or properties in ontolog talk), the patients couldn’t use
multiple properties, and relied on just one instead, leading to errors of
perception and interpretation.
It occurred to me that this model of hub
and spoke diversity in human concepts and concept learning has some suggestive
value re why it is so difficult to get consistent naming of concepts as common
as “river”s.
-Rich
Sincerely,
Rich Cooper
EnglishLogicKernel.com
Rich AT EnglishLogicKernel DOT com
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