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Missile Defense

Russian military leaders have expressed concern about US plans for a national missile defense system. Will defense technology be limited by possibilities for a strategic imbalance? Is this just SDI all over again?

rshowalter - 12:58pm Mar 16, 2001 EST (#1074 of 1076)
Robert Showalter showalte@macc.wisc.edu

I’m quoting here from THE STRUCTURE OF SCIENTIFIC REVOLUTIONS 2nd Ed. by Thomas S. Kuhn, , at the end of Chapter 6 “Anomaly and the Emergence of Scientific Discoveries”

The perceptual problems described here can and do occur on the issues that divide the US, Russia, and the rest of the world.

“ To a greater or lesser extent (corresponding to the continuum from the shocking to the anticipated result), the characteristics are common to all discoveries from which new sorts of phenomena emerge. Those characteristics include: the previous awareness of anomaly, the gradual and simultaneous emergence of both observational and conceptual recognition, and the consequent change of the paradigm categories and procedures often accompanied by resistance. There is even evidence that these same characteristics are built into the nature of the perceptual process itself. In a psychological experiment that deserves to be far better known outside the trade, Bruner and Postman asked experimental subjects to identify on short and controlled exposure a series of playing cards. (J.S.Bruner and Leo Postman “On the Perception of Incongruity: A Paradigm,” Journal of Personality, XvIII (1949) 206-23 ) Many of the cards were normal, but some were made anomalous, e.g., a red six of spades and a black four of hearts. Each experimental run consisted of the display of a single card to a single subject in a series of gradually increased exposures. After each exposure the subject was asked what he had seen, and the run was terminated by two successive correct identifications.

“ Even on the shortest exposures many subjects identified most of the cards, and after a small increase all of the subjects identified them all. For the normal cards these identifications were usually correct, but the anomalous cards were almost always identified, without apparent hesitation or puzzlement, as normal. The black four of hearts might, for example, be identified as the four of either spades or hearts. Without any awareness of trouble, it was immediately fitted to one of the conceptual categories prepared by prior experience. One would not even like to say that the subjects had seen something different from what they identified. With a further increase in exposure to the anomalous cards, subjects did begin to hesitate and to display awareness of anomaly. Exposed, for example, to the red six of spades, some would say: “That’s the six of spades, but there’s something wrong with it- the black has a red border.” Further increase in exposure resulted in still more hesitation and confusion, until finally and sometimes quite suddenly, most subjects would produce the correct identification without hesitation. Moreover, after doing this with two or three anomalous cards, they would have little difficulty with the others. A few subjects, however, were never able to make the requisite adjustment of their categories. Even at forty times the average exposure required to recognize normal cards for what they were, more than 10 per cent of the anomalous cards were not correctly identified. And the subjects who then failed often experienced acute personal distress. One of them exclaimed: “I can’t make the suit out, whatever it is. It didn’t even look like a card that time. I don’t know what color it is now, or whether it’s a spade of a heart. I’m not sure now what a spade looks like. My God!” In the next section, we shall occasionally see scientists behaving this way, too.

“ Either as a metaphor, or because it reflects the nature of the mind, that psychological experiment provides a wonderfully simple and cogent schema for the process of scientific discovery. In science, as in the playing card experiment, novelty emerges only with difficulty, manifested by resistance, against a background provided by expectation. Initially, only the anticipated and usual are experienced, even under circumstances where the anomaly is later to be observed. Further acquaintance, howev

rshowalter - 01:01pm Mar 16, 2001 EST (#1075 of 1076)
Robert Showalter showalte@macc.wisc.edu

Further acquaintance, however, does result in awareness of something that has gone wrong before. That awareness of anomaly opens up a period in which conceptual categories are adjusted until the initially anomalous has become the anticipated. At this point the discovery has been completed. . . . . “ (End of quote from Kuhn)