Download Homework 6: Can a computer think

Homework 6: Can a computer think?
Is artificial intelligence really possible? What is necessary for thought? What would a
computer have to have in order to think?
Here are a couple of ways that this issue has been examined in the past (adapted from
Readings in Language and Mind ed. By Heimir Geirsson and Michael Losonsky):
I. The Turing Test, from Alan Turing’s celebrated paper “Computing Machinery and
Intelligence” (1950).
Can a machine successfully play the imitation game? The original imitation game
is played by three people: a male, a female, and an interrogator who cannot see or hear
the other two players. The interrogator’s task is to find out who is male and who is female
on the basis of written questions and answers. What makes the game interesting is that
one of the players tries to fool the interrogator about his or her sexual identity while the
other player gives honest answers. The Turing Test replaces the two players of different
sexes with a human and a digital computer. The interrogator’s objective is to determine
which of the two players is human and which is the computer. Turing’s question is “Will
the interrogator decide wrongly as often when the game is played like this as when it is
played with a male and a female?” Turing believed this would be possible within 50
years of writing his article.
Turing’s work suggested that intelligence in general, including human
intelligence, should be characterized in terms of the carrying out of a computation over
uninterpreted symbols according to a finite set of rules. This has been the cornerstone of
classical artificial intelligence. The basic idea is that in some sense our brains implement
a set of symbols and rules for manipulating symbols in much the same way that your PC
stores symbols and programs.
II. Searle’s Chinese Room, from his paper “Is the Brain’s Mind a Computer Program?”
(1980).
Searle challenged the Turing Test in the following way. Imagine a non-Chinese
speaker locked in a room with a rule book in English matching Chinese symbols with
other Chinese symbols. The rules identify the symbols entirely by their shapes, not by
their meanings. Outside of the room there is a small group of people who understand
Chinese and who hand the non-Chinese speaker Chinese symbols to which she is
supposed to respond with the help of the rule book. With this help, the non-Chinese
speaker is able to respond to the symbols in a way that might be expected of a native
Chinese speaker. In other words, she passes the Turing Test. In spite of that, Searle points
out, she does not understand Chinese, nor is it plausible to claim that the room
understands Chinese.
If we look at the rule book as being a computer program, the non-Chinese speaker
as being the processor, those who wrote the rule book as the programmers, the input as
data and the output as answers, then we can look at the Chinese room as being a symbol
processor, much like computers. Given that, and given that the system (the Chinese
room) does not understand Chinese, Searle concludes that no pure syntax processor is
capable of thought and understanding. Thought requires mental content, or semantics,
and syntax does not yield semantics, Searle argues.