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PHYSICS DF THE IMPOSSIBLE
Simple computer programs have been written by scientists, such
as ELIZA, that can mimic conversational speech and hence fool most
unsuspecting people into believing they are speaking to a human.
(Most human conversations, for example, use only a few hundred
words and concentrate on a handful of topics.) But so far no computer
program has been written that can fool people who are specifically trying to determine which box contains the human and which contains
the machine. (Turing himself conjectured that by the year 2000, given
the exponential growth of computer power, a machine could be built
that would fool 50 percent of the judges in a five-minute test.)
A small army of philosophers and theologians has declared that it
is impossible to create true robots that can think like us. John Searle,
a philosopher at the University of California at Berkeley, proposed the
"Chinese room test" to prove that AI is not possible. In essence, Searle
argues that while robots may be able to pass certain forms of the Turing test, they can do so only because they blindly manipulate symbols
without the slightest understanding of what they mean.
Imagine that you are sitting inside the box and you don't understand a word of Chinese. Assume you have a book that allows you to
rapidly translate Chinese and manipulate its characters. If a person
asks you a question in Chinese, you merely manipulate these strangelooking characters, without understanding what they mean, and give
credible answers.
The essence of his criticism boils down to the difference between
syntax and semantics. Robots can master the syntax of a language (e.g.,
manipulating its grammar, its formal structure, etc.) but not its true semantics (e.g., what the words mean). Robots can manipulate words
without understanding what they mean. (This is somewhat similar to
talking on the phone to an automatic voice message machine, where
you have to punch in "one," "two," etc., for each response. The voice at
the other end is perfectly capable of digesting your numerical responses, but is totally lacking in any understanding.)
Physicist Roger Penrose of Oxford, too, believes that artificial intelligence is impossible; mechanical beings that can think and possess
human consciousness are impossible according to the laws of the
PHYSICS DF THE IMPOSSIBLE
Simple computer programs have been written by scientists, such
as ELIZA, that can mimic conversational speech and hence fool most
unsuspecting people into believing they are speaking to a human.
(Most human conversations, for example, use only a few hundred
words and concentrate on a handful of topics.) But so far no computer
program has been written that can fool people who are specifically trying to determine which box contains the human and which contains
the machine. (Turing himself conjectured that by the year 2000, given
the exponential growth of computer power, a machine could be built
that would fool 50 percent of the judges in a five-minute test.)
A small army of philosophers and theologians has declared that it
is impossible to create true robots that can think like us. John Searle,
a philosopher at the University of California at Berkeley, proposed the
"Chinese room test" to prove that AI is not possible. In essence, Searle
argues that while robots may be able to pass certain forms of the Turing test, they can do so only because they blindly manipulate symbols
without the slightest understanding of what they mean.
Imagine that you are sitting inside the box and you don't understand a word of Chinese. Assume you have a book that allows you to
rapidly translate Chinese and manipulate its characters. If a person
asks you a question in Chinese, you merely manipulate these strangelooking characters, without understanding what they mean, and give
credible answers.
The essence of his criticism boils down to the difference between
syntax and semantics. Robots can master the syntax of a language (e.g.,
manipulating its grammar, its formal structure, etc.) but not its true semantics (e.g., what the words mean). Robots can manipulate words
without understanding what they mean. (This is somewhat similar to
talking on the phone to an automatic voice message machine, where
you have to punch in "one," "two," etc., for each response. The voice at
the other end is perfectly capable of digesting your numerical responses, but is totally lacking in any understanding.)
Physicist Roger Penrose of Oxford, too, believes that artificial intelligence is impossible; mechanical beings that can think and possess
human consciousness are impossible according to the laws of the