Page 101 - Foundations of Cognitive Psychology : Core Readings

102 John R. Searle

sort of thing think they can get away with it because they don’t really take it
seriously, and they don’t think anyone else will either. I propose, for a moment
at least, to take it seriously. Think hard for one minute about what would be
necessary to establish that that hunk of metal on the wall over there had real
beliefs, beliefs with direction of fit, propositional content, and conditions of
satisfaction; beliefs that had the possibility of being strong beliefs or weak
beliefs; nervous, anxious, or secure beliefs; dogmatic, rational, or superstitious
beliefs; blind faiths or hesitant cogitations; any kind of beliefs. The thermostat
is not a candidate. Neither is stomach, liver, adding machine, or telephone.
However, since we are taking the idea seriously, notice that its truth would be
fatal to strong AI’s claim to be a science of the mind. For now the mind is
everywhere. What we wanted to know is what distinguishes the mind from
thermostats and livers. And if McCarthy were right, strong AI wouldn’t have a
hope of telling us that.

5.2 The Robot Reply (Yale)

‘‘Suppose we wrote a different kind of program from Schank’s program. Sup-
pose we put a computer inside a robot, and this computer would not just take
in formal symbolsasinput andgiveout formal symbolsasoutput, butrather
would actually operate the robot in such a way that the robot does something
very much like perceiving, walking, moving about, hammering nails, eating,
drinking—anything you like. The robot would, for example, have a television
camera attached to it that enabled it to ‘see,’ it would have arms and legs that
enabled it to ‘act,’ and all of this would be controlled by its computer ‘brain.’
Such a robot would, unlike Schank’s computer, have genuine understanding
and other mental states.’’
The first thing to notice about the robot reply is that it tacitly concedes that
cognition is not solely a matter of formal symbol manipulation, since this reply
adds a set of causal relation with the outside world (cf. Fodor, 1980). But the
answer to the robot reply is that the addition of such ‘‘perceptual’’ and ‘‘motor’’
capacities adds nothing by way of understanding, in particular, or intention-
ality, in general, to Schank’s original program. To see this, notice that the same
thought experiment applies to the robot case. Suppose that instead of the com-
puter inside the robot, you put me inside the room and, as in the original Chi-
nese case, you give me more Chinese symbols with more instructions in English
for matching Chinese symbols to Chinese symbols and feeding back Chinese
symbols to the outside. Suppose, unknown to me, some of the Chinese symbols
that come to me come from a television camera attached to the robot and other
Chinese symbols that I am giving out serve to make the motors inside the robot
move the robot’s legs or arms. It is important to emphasize that all I am doing
is manipulating formal symbols: I know none of these other facts. I am receiv-
ing ‘‘information’’ from the robot’s ‘‘perceptual’’ apparatus, and I am giving out
‘‘instructions’’ to its motor apparatus without knowing either of these facts. I
am the robot’s homunculus, but unlike the traditional homunculus, I don’t
know what’s going on. I don’t understand anything except the rules for symbol
manipulation. Now in this case I want to say that the robot has no intentional