@InBook{,
ALTauthor = {Douglas R. Hofstadter and Melanie Mitchell},
ALTeditor = {Douglas R. Hofstadter and the Fluid
Analogies Research group},
title = {Fluid Concepts and Creative Analogies},
chapter = {The copycat project: A model of
mental fluidity and analogy-making},
publisher = {Basic Books},
year = {1995},
OPTpages = {205--267},
}
Architecture is a hybrid of symbolic and connectionist.
[206] example from the problem domain: abc : abd :: ijk : ?
Where the agent is expected to do the same thing to ijk that was done
to abc.
aabc : aabd :: ijkk : ?
If you answer ijll, then you are
demonstrating fluidity and conceptual slippage, where the rightmost
letter has slipped to the rightmost group of letters. Other kinds of
things that can slip: leftmost with rightmost, successor and
predecessor.
One might also see that aa and kk play similar "roles" in each of these. [207]
[208] "All the features of the Copycat architecturee were in fact designed with an eye to great generality...the Copycat project is not about simulating analogy-making per se, but about simulating the very crux of human cognition: fluid concepts."
"...even the most abstract and sophisticated mental acts deeply resemble perception." [210]
The Architecture has three major components [211]
[213] "The further away from direct perception, the more likely it is to be involved in what people consider to be the essence of the situation."
Because of this, unlike Gentner (1983), attributes (e.g. alphabetic-first) are stronger than relations (e.g. successor).
Links are labeled; the labels are concepts in themselves. The label's activation determines the length of the link. E.g. opposite links left and right.
Slippage is easier with shorter links.[214] The probabilistic cloud around a node is called a halo. [215] The net changes during the course of a run, but doesn't change permanently as a result. New concepts are not created.[216]
An object's salience is a function of its importance and unhappiness. Importance is a function of activation level and the number of descriptions it has. Unhappiness is poor its links are to other concepts. Unhappy objects get more attention.
Objects can get linked by bonds, such as "sameness" for k and k. Bond have strengths based on activation, depth, and having similar bonds [218]. Objects linked with a uniform bond become chunked into groups. Groups also have desceriptions, salience, strength, and can bond, be scanned, and become parts of higher level groups.
Bridges are formed between two differnt frameworks (letterstrings, in this domain). This is an analogical map. Bridges have strengths, "depending on the ease of the slippages it entailed." [219]
Viewpoints are sets of mappings.
Botom up codlets notice all the time. Top down codelets look for higher level relations and can be called only by the slipnet. activated nodes can spawn them, as well as various "pressures" such as salience of workspace objects, and the activation, depth and stength of other nodes. .[223]
Bottom up codelets are constantly being added to the coderack, and codelets can call other codelets.,
[226] The workspace can only have one viewpoint at a time. Scouts can try to topple it, though, and bring about a different viewpoint.
[228] Temperature is a measure of how confident the workspace is with its viewpoint, inversely. Temperature controls the degree of randomness in decision making. Final temperature is a measure of how confident the system is in its answer.
[236]"...it is not intended that they shuld precisely reproduce the frequencies one would find if this problem were posed to humans, since, as we said earlier, the program is not meant to model all the domain0specific mechanisms people use in solving these letter-string problems."