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Minds, Brains, and Programs  105

               accordance with a bunch of rules. Furthermore, suppose the man knows none
               of these facts about the robot, all he knows is which operations to perform on
               which meaningless symbols. In such a case we would regard the robot as an
               ingenious mechanical dummy. The hypothesis that the dummy has a mind
               would now be unwarranted and unnecessary, for there is now no longer any
               reason to ascribe intentionality to the robot or to the system of which it is a part
               (except of course for the man’s intentionality in manipulating the symbols). The
               formal symbol manipulations go on, the input and output are correctly matched,
               but the only real locus of intentionality is the man, and he doesn’t know any of
               the relevant intentional states; he doesn’t, for example, see what comes into the
               robot’s eyes, he doesn’t intend to move the robot’s arm, and he doesn’t under-
               stand any of the remarks made to or by the robot. Nor, for the reasons stated
               earlier, does the system of which man and robot are a part.
                 To see this point, contrast this case with cases in which we find it completely
               natural to ascribe intentionality to members of certain other primate species
               such as apes and monkeys and to domestic animals such as dogs. The reasons
               we find it natural are, roughly, two: we can’t make sense of the animal’s be-
               havior without the ascription of intentionality, and we can see that the beasts
               are made of similar stuff to ourselves—that is an eye, that a nose, this is its
               skin, and so on. Given the coherence of the animal’s behavior and the assump-
               tion of the same causal stuff underlying it, we assume both that the animal
               must have mental states underlying its behavior, and that the mental states
               must be produced by mechanisms made outofthe stuffthatislikeour stuff.
               We would certainly make similar assumptions about the robot unless we had
               some reason not to, but as soon as we knew that the behavior was the result of
               aformalprogram,and that theactualcausalpropertiesofthe physical sub-
               stance were irrelevant we would abandon the assumption of intentionality (See
               ‘‘Cognition and Consciousness in Nonhuman Species,’’ The Behavioral and Brain
               Sciences (1978), 1 (4)).
                 There are two other responses to my example that come up frequently (and
               so are worth discussing) but really miss the point.


               5.5 The Other Minds Reply (Yale)
               ‘‘How do you know that other people understand Chinese or anything else?
               Only by their behavior. Now the computer can pass the behavioral tests as well
               as they can (in principle), so if you are going to attribute cognition to other
               people you must in principle also attribute it to computers.’’
                 This objection really is only worth a short reply. The problem in this discus-
               sion is not about how I know that other people have cognitive states, but rather
               what it is that I am attributing to them when I attribute cognitive states to
               them.The thrust of theargumentisthatit couldn’tbejustcomputationalpro-
               cesses and their output because the computational processes and their output
               can exist without the cognitive state. It is no answer to this argument to feign
               anesthesia. In ‘‘cognitive sciences’’ one presupposes the reality and knowability
               of the mental in the same way that in physical sciences one has to presuppose
               the reality and knowability of physical objects.
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