From the point of view of evolution, prejudice is an alerting signal, warning tribal mammals that a potentially dangerous alien mammal is in the vicinity, and should be fought or fled. Alerting mechanisms respond to novelties in the environment, because novelties represent change from the usual, and are, therefore, potentially important.
One of two things can happen: (1) If the alerting mechanism is very strongly activated, it will produce an unendurable emotional state, forcing the tribal mammal to fight the novelty or flee it. (2) If, however, the novelty is either low-grade, or simply odd without being threatening, the alerting mechanism will be mildly activated, producing an emotional state that, if other environmental circuмstances militate against it, will be too weak to motivate any actual behavioral response.
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Turning Associative Conditioning and Direct Emotional Modeling against themselves, we Jam by forging a fresh link between, on one hand, some part of the mechanism, and, on the other, pre-existing, external, opposed, and therefore incompatible emotional response. Ideally, the bigot being subjected to such counterconditioning will ultimately experience two emotional responses to the hated object, opposed and competing. The consequent internal confusion has two effects: first, it is unpleasant --we can call it 'emotional dissonance' after Festinger-- and will tend to result in an alteration of previous beliefs and feelings so as to resolve the internal conflict. Since the weaker of the clashing emotional associations is more likely to give way, we can achieve optimal results by linking the prejudicial response to a stronger and more fundamental structure of belief and emotion.
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Desensitization aims at lowering the intensity of antigαy emotional reactions to a level approximating sheer indifference; Jamming attempts to blockade or counteract the rewarding 'pride in prejudice' (peace, Jane Austen!) by attaching to homohatred a pre-existing, and punishing, sense of shame in being a bigot, a horse's ass, and a beater and a murderer. Both desensitization and Jamming, though extremely useful, are more preludes to our highest --though necessarily very long-range-- goal, which is Conversion.
... Put briefly, if Desensitization lets the watch run down, and Jamming throws sand in the works, Conversion reverses the spring so that the hands run backwards.
Conversion makes use of Associative Conditioning, much as Jamming does-- indeed, in practice the two processes overlap-- but far more ambitiously. In Conversion, the bigot, who holds a very negative stereotypic picture, is repeatedly exposed to literal picture/label pairs, in magazines, and on billboards and TV, of gαys --explicitly labeled as such!-- who not only don't look like his picture of a ɧoɱosɛҳųαƖ, but are carefully slected to look either like the bigot an dhis friends, or like any one of his other stereotypes of all-right guys.
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When a bigot is presented with an image of the sort of person whom he already has a positive stereotype, he experiences an involuntary rush of positive emotion, of good feeling; he's been conditioned to experience it. But, here, the good picture has a bad label --gαy! The bigot will feel two incompatible emotions: a good response to the picture, a bad response to the label. At worst, the two will cancel one another, and we will have successfully Jammed, as above. At best, Associative Conditioning will, to however small and extent, transfer the positive emotion associated with the picture to the label itself, not immediately replacing the negative response, but definitely weakening it. In Conversion, we mimic the natural process of stereotype learning, with the following effect: we take the bigot's good feelings about all-right guys, and attach them to the label 'gαy' either weakening or, eventually, replacing his bad feelings toward the label and the prior stereotype.
Taken from, After the Ball by Kirk and Madsen