Coherence in Thought and Action

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Joined  24-12-2004
03 January 2005 13:00

From the book inside leaf cover:

"This book is an essay of how people make sense of each other and the world they live in"

(Disclosure: i, lawrence turner, have no financial interests what so ever in this book. Personally: i see this book as an enlightening tool in the understanding of how concepts of reality work on the human psyche: i recommend it)

Coherence in Thought and Action

Explanatory and deductive coherence both involve propositional elements, but not all knowledge is verbal. Our perceptual knowledge includes visual, auditory, olfactory, and tactile representations of what we see, hear, smell, and feel. No ‘sensation' is simply a matter of taking sensory inputs and transforming them directly into interpretations that form part of conscious experience, because the sensory inputs are often incomplete or ambiguous.

Different kinds of coherence are distinguished from each other by the different kinds of elements and constraints they involve. In explanatory coherence, the elements are propositions and the constraints are explanation- related, but in conceptual coherence the elements are concepts and the constraints are derived from positive and negative associations among concepts.

Taken together, these principles explain how people decide what complexes of concepts apply to a particular object. The association of concepts can be understood in terms of social stereotypes.

Conceptual coherence can be characterized with principles similar to those for other kinds of coherence, these include: symmetric relation between pairs of concepts, concept coheres with another concept (+), applicability of a concept to an object, concept incoheres with another concept (-) and applicability of a concept to an object depends on the applicability of other concepts.

Many psychological phenomena concerning how people apply stereotypes can be explained in terms of conceptual-constraint satisfaction.

Although construction workers are stereotyped as more aggressive than accountants, a construction worker and an accountant were viewed as equally unaggressive after having failed to react to an insult, an unaggressive behavior. Even though the stereotypes no longer affected trait ratings, they continued to influence predictions about the individual's behavior: the construction worker was still viewed as more likely than the accountant to engage in coarse aggressive behaviors such as punching and cursing.

There are thus five primary kinds of coherence relevant to assessing knowledge: explanatory, analogical, deductive, perceptual, and conceptual. (A sixth kind, deliberative coherence, is relevant to decision making and ethics.)

Each kind of coherence involves a set of elements and positive negative constraints.

There are important differences between their fundamental coherence relations and the associated principles. Deductive coherence is based on purely deductive relations between propositions. In contrast, although explanation may sometimes involve deduction, as in theories in mathematical physics, it is fundamentally a matter of there being a causal relation between what is explained and the representations that do the explaining.

There is abundant experimental and computational evidence that concepts are a psychologically realistic kind of mental representation not reducible to propositions (at this time -lt).

Generation of new elements is sometimes driven by incoherence.

For example, I am trying to understand someone but fail to form a coherent impression or attribution, I may be spurred to form new elements that can add coherence to the old set of elements.

If I am told that someone is a Harvard-educated carpenter, it may be difficult to reconcile the conflicting expectations associated with the two concepts. Surprise is an emotional reaction that signals that a satisfactory degree of coherence has not been achieved. This reaction triggers hypothesis formation, as I ask myself how someone with a Harvard degree could end up working as a carpenter.

Explanatory, analogical, deductive, visual, and conceptual coherence add up to a comprehensive, computable, naturalistic theory of epistemic coherence.

The nature of the elements are defined by the positive and negative constraints that hold between them. Once the elements and constraints have been specified, it is possible to use connectionist algorithms to compute coherence, accepting and rejecting elements in a way that approximately maximizes compliance with the coherence conditions.

Computing coherence can then be as exact as deduction or probabilistic reasoning, and can avoid the problems of computational intractability that arise with them.

Being able to do this computation does not, of course, help with the problem of generating elements and constraints, but it does show how to make a judgment of coherence with the elements and constraints on hand.

Arriving at a rich, coherent set of elements-scientific theories, ethical principles, or whatever - is a very complex process that intermingles both assessment of coherence and generation of new elements.

-Paul Thagard, Professor of Philosophy and Director of Cognitive Science Program @ University of Waterloo, Ontario, Canada

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