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Artificial Intelligence
As a theory in the philosophy of mind, artificial intelligence (or AI)
is the view that human cognitive mental states can be duplicated in
computing machinery. Accordingly, an intelligent system is nothing but
an information processing system. Discussions of AI commonly draw a
distinction between weak and strong AI. Weak AI holds that suitably
programmed machines can simulate human cognition. Strong AI, by
contrast, maintains that suitably programmed machines are capable of
cognitive mental states. The weak claim is unproblematic, since a
machine which merely simulates human cognition need not have conscious
mental states. It is the strong claim, though, that has generated the
most discussion, since this does entail that a computer can have
cognitive mental states. In addition to the weak/strong distinction,
it is also helpful to distinguish between other related notions.
First, cognitive simulation is when a device such as a computer simply
has the same the same input and output as a human. Second, cognitive
replication occurs when the same internal causal relations are
involved in a computational device as compared with a human brain.
Third, cognitive emulation occurs when a computational device has the
same causal relations and is made of the same stuff as a human brain.
This condition clearly precludes silicon-based computing machines from
emulating human cognition. Proponents of weak AI commit themselves
only to the first condition, namely cognitive simulation. Proponents
of strong AI, by contrast, commit themselves to the second condition,
namely cognitive replication, but not the third condition.
Proponents of strong AI are split between two camps: (a) classical
computationalists, and (b) connectionists. According to classical
computationalism, computer intelligence involves central processing
units operating on symbolic representations. That is, information in
the form of symbols is processed serially (one datum after another)
through a central processing unit. Daniel Dennett, a key proponent of
classical computationalism, holds to a top-down progressive
decomposition of mental activity. That is, more complex systems break
down into more simple ones, which end in binary on-off switches. There
is no homunculi, or tiny person inside a cognitive system which does
the thinking. Several criticisms have been launched against the
classical computationalist position. First, Dennett's theory, in
particular, shows only that digital computers do not have homunculi.
It is less clear that human cognition can be broken down into such
subsystems. Second, there is no evidence for saying that cognition is
computational in its structure, rather than saying that it is like
computation. Sinc |