This work investigates some of the issues and consequences for the field of artificial
intelligence and cognitive science, which are related
to the perceived limits of computation
with current digital equipment. The Church
-
Turing thesis and the specific properties of Turing
machines are examined and some of the philosophical ‘in principle’ objections, such as the
application of Gödel’s incompl
eteness theorem, are discussed. It is argued that the
misinterpretation of the Church
-
Turing thesis has led to unfounded assumptions about the
limitations of computing machines in general. Modern digital computers, which are based on
the von Neuman archite
cture, can typically be programmed so that they interact effectively
with the real word. It is argued that digital computing machines are supersets of Turing
machines, if they are, for example, programmed to interact with the real world. Moreover,
computin
g is not restricted to the domain of discrete state machines. Analog computers and
real or simulated neural nets exhibit properties that may not be accommodated in a definition
of computing, which is based on Turing machines. Consequently, some of the phil
osophical
‘in principle’ objections to artificial intelligence may not apply in reference to engineering
efforts in artificial intelligenc