Steven Pinker -- How the Mind Works - Hampshire High Italian ...

126 HOW THE MIND WORKSI he human mind must be given credit for one more cognitive feat that isdifficult to wring out of connectoplasm, and therefore difficult to explainby associationism. Neural networks easily implement a fuzzy logic inwhich everything is a kind-of something to some degree. To be sure, manycommon-sense concepts really are fuzzy at their edges and have no cleardefinitions. The philosopher Ludwig Wittgenstein offered the example of"a game," whose exemplars (jigsaw puzzles, roller derby, curling, Dungeonsand Dragons, cockfighting, and so on) have nothing in common, and earlierI gave you two others, "bachelor" and "vegetable." The members of afuzzy category lack a single defining feature; they overlap in many! features,much like the members of a family or the strands of a rope, none of whichruns the entire length. In the comic strip Bloom County, Opus the Penguin,temporarily amnesic, objects when he is told he is a bird. Birds aresvelte and aerodynamic, he points out; he is not. Birds can fly; he cannot.Birds can sing; his performance of "Yesterday" left his listeners gagging.Opus suspects he is really Bullwinkle the Moose. So even concepts like"bird" seem to be organized not around necessary and sufficient conditionsbut around prototypical members. If you look up bird in the dictionary, itwill be illustrated not with a penguin but with Joe Bird, typically a sparrow.Experiments in cognitive psychology have shown that people arebigots about birds, other animals, vegetables, and tools. People sharea stereotype, project it to all the members of a category, recognize thestereotype more quickly than the nonconformists, and even claim tohave seen the stereotype when all they really saw were examples similarto it. These responses can be predicted by tallying up the properties thata member shares with other members of the category: the more birdyproperties, the better the bird. An auto-associator presented with examplesfrom a category pretty much does the same thing, because it computescorrelations among properties. That's a reason to believe that partsof human memory are wired something like an auto-associator.But there must be more to the mind than that. People are not alwaysfuzzy. We laugh at Opus because a part of us knows that he really is abird. We may agree on the prototype of a grandmother—the kindly, grayhairedseptuagenarian dispensing blueberry muffins or chicken soup(depending on whose stereotype we're talking about)—but at the sametime we have no trouble understanding that Tina Turner and Elizabeth