Can Computers Really Think? - Thinking as Computation - page 268

Of course, there is a lot of thinking that the topic did not talk about at all. What
about the thinking that goes into designing a bridge or composing a piece of music?
What about following the dialogue in a play? What about the sort of thinking that
occurs when recalling a childhood event or daydreaming? What about meditation?
What about the role of emotion? An account of thinking that is true to the very wide
range of mental experiences people have would go well beyond what was considered
here.
But nonetheless, even within a limited context, and despite all the restrictions, this
book still raises a philosophical question. If it is true that thinking (or some forms of
it) can be understood as computation, does it then not follow that given the right
program, a computer is able to think?
For many people, this is a very troubling idea. Thinking and the intelligent behavior
it gives rise to feel very special to us. At its most elevated, we might say, thinking
defines what it means to be human. The idea that a gadget like an electronic computer
might also be able to think is unsettling.
Looking back at what was accomplished in previous chapters, was it really possi-
ble to program a computer to think about the grandfather relation, the objects in a
scene, the words in a sentence, the ways to achieve a goal? Or was the computer just
programmed to behave as if it were thinking? Is there a difference?
This final chapter briefly explores these philosophical questions.
12.1 What computers can do
Can a computer really think? Before answering, consider a question that is even
more basic: Can a computer really add two numbers? Many of us, would say yes: a
suitably programmed computer can take two numbers as input and return their sum
as output. Nobody disputes this. If this is not adding two numbers, then what is?
But nothing is taken for granted in philosophy. In fact, some might be tempted by
an account like the following:
Computers cannot do addition, really. All they can do is mechanically shuffle
around uninterpreted symbols. It is we, the human beings, who interpret this
shuffling. In some cases, we might interpret it as addition, say. But this is up to
us, and someone else might interpret the shuffling completely differently, like
solving a puzzle or playing some sort of mysterious game. At any rate, for the
computer itself, no arithmetic is involved.