Earl MacCormac
If we accept that literal truth, falsity and figurality form a continuum rather than a discrete set, then this entails a
clear violation of the law of the excluded middle, should ever a logical analysis of metaphor be pursued. Such a
fuzzy-logical approach has been formalised by Earl MacCormac (1985), in a four-valued logic which not only
accommodates truth and falsity, but, following Wheelwright (1962), also embraces metaphor in two forms,
Epiphor and Diaphor. A diaphor is a novel metaphor which strikes a discordant note, evoking emotive tension in
the listener; diaphors initially suggest more dissimilarities that commonalties between the tenor and vehicle,
which may have to be reconciled by a change of representation (see Indurkhya 1992). Epiphors are
conventionalised or comparison-centred metaphors which have lost their emotive force and which no longer
challenge existing conceptual representations.
Employing a system of fuzzy semantic markers, MacCormac defines the fuzzy membership of one category in
another as a real number ranging from zero (absolute falsehood) to one (undeniable truth). Within this range
exist the delimiters a, b, c, such that 0
> a < b < c < 1, where the interval 0 to a represents falsehood, a to b
represents diaphor, b to c represents epiphor, and c to 1 represents literal truth. Metaphoric set membership is
thus indicated by a value in the range a to c. Novel metaphors begin life as diaphors, and migrate along this fuzzy
scale into epiphors as they lose their emotive tension through commonplace use, to eventually find rest as dead
metaphors in the literal truth interval. MacCormac argues for the necessity of literal truth in this model, though
it is hard to view it here as anything but a carry-over from previous marker schemes, where an attempt is made to
impose an a priori division between semantic validity and anomaly. As we have seen, such a division makes no
allowance for contextual influence and is thus incapable of an adequate treatment of metaphor. Given the correct
poetic setting, even hoary old anomalies such as `Colourless green ideas dream furiously' can be granted a
valid interpretation. What distinguishes diaphor from anomaly is the existence of a context which supports a
metaphoric reading, not an artificial delimiter on a fuzzy scale.
While the distinction between truth, anomaly and metaphor is artificial, so too is the distinction between epiphor
and diaphor. These forms of metaphor most likely require different forms of processing (if the distinction is to
be worth making at all), such that passing the fixed threshold (b) on the fuzzy scale will result in a radical
reappraisal of content. But this sudden discontinuity of interpretation contradicts the continuous nature of the
underlying fuzzy system. By way of analogy, consider a car which is driving down the motorway, gradually
accelerating as it goes. As the car passes 55 m.p.h. the driver is suddenly classified as a speeder. This somewhat
arbitrary, imposed discontinuity serves a useful classification task in allowing the police to recognise
potentially dangerous drivers. However, it reveals nothing about the mechanics of the engine powering the car,
which doesn't perform in a qualitatively different manner after the speed limit is surpassed. Neither does a
second engine kick in above certain speeds. In this sense MacCormac's model makes good a posteriori
philosophy but comes up short as a cognitive model. A more realistic model which preserves continuity is one
in which metaphors are processed homogeneously, and the epiphor/diaphor distinction is used to measure the
quantity of processing performed.
http://www.thymos.com/mind/m.html A very similar discussion.
http://www.birdhouse.org/words/baald/metaphor.html
