The Creative Mind: Myths and Mechanisms, Second Edition - Index of

CONCEPTS OF COMPUTATION
Kekulé’s intuitive leap from strings to rings extended the representational
system then used in chemistry.
Some of the most important human creations have been new representational
systems. These include formal notations, such as Arabic
numerals (not forgetting zero), chemical formulae, or the staves, minims,
and crotchets used by musicians. Programming languages are a more
recent example, being notational systems that make it possible to state –
and to develop – effective procedures of many different kinds.
As well as recording new ideas for posterity, such notations may make
them possible in the first place. For a written language can help us to
explore the implications of the ideas it represents. It enables us to write
down, and so remember, our previous thoughts – including the passing
thoughts, or ‘intermediate results’, crucially involved in reaching a
conclusion.
An adequate explanation of creativity should include a systematic
theory explaining how, and why, different sorts of representation are
appropriate to different classes of problem. As yet, no such theory exists.
But representation, and the difference it makes to problem-solving, is
much studied in AI.
Various methods of representing knowledge have been used in
computer programs, including scripts, frames, and semantic nets – sometimes
called associative nets. (Each of these concepts will be explained
soon.) In addition, some theoretical AI-research has tried to distinguish
general types of representation; an example discussed below is analogical
representation, of which Longuet-Higgins’ array-and-boxes is a
special case.
The concept of semantic net originated in psychology. It depicts
human memory as an associative system wherein each idea can lead
to many other relevant ideas – and even to ‘irrelevant’ ideas, linked to the
first by phonetic similarity or even by mere coincidence. For instance,
violet may call to mind not only colour and flower, but also living, woodland,
springtime and violence and viable – and even (for someone like myself,
whose mother’s name was Violet) mother; each of these ideas has further
associations (springtime with Paris, for example), and so on.
Semantic nets in AI are computational structures representing (in a
highly simplifed way) the field of meaning within a certain part of conceptual
space. They are often used not for doing ‘logical’ problemsolving,
but for modelling spontaneous conceptual associations. It’s those
associations which are the basis of combinational creativity (see Chapter 6).
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