[ExI] The symbol grounding problem in strong AI

[Stathis Papaioannou]

2009/12/15 Gordon Swobe <gts_2000 at yahoo.com>:

> Crick (1994) proposed tentatively that the neuronal correlates of consciousness may be found in neuronal firings in the 40hz range in networks of the thalamocortical system, specifically in connections between the thalamus and layers four and six of the cortex. Searle applauds this sort of research program (he references Crick's hypothesis in his own paper on consciousness) because on his view we need to understand how the brain does the consciousness trick before we can understand how it does the symbol grounding trick.

The technical details of how the brain produces consciousness are of
course important, but they are not relevant to the philosophical
argument. Searle admits that the brain can be simulated by a computer,
but he doesn't think this simulation would give rise to consciousness:

http://users.ecs.soton.ac.uk/harnad/Papers/Py104/searle.comp.html

<The answer to 3. seems to me equally obviously "Yes", at least on a
natural interpretation. That is, naturally interpreted, the question
means: Is there some description of the brain such that under that
description you could do a computational simulation of the operations
of the brain. But since according to Church's thesis, anything that
can be given a precise enough characterization as a set of steps can
be simulated on a digital computer, it follows trivially that the
question has an affirmative answer. The operations of the brain can be
simulated on a digital computer in the same sense in which weather
systems, the behavior of the New York stock market or the pattern of
airline flights over Latin America can. So our question is not, "Is
the mind a program?" The answer to that is, "No". Nor is it, "Can the
brain be simulated?" The answer to that is, "Yes". The question is,
"Is the brain a digital computer?" And for purposes of this discussion
I am taking that question as equivalent to: "Are brain processes
computational?">

So, Searle allows that the behaviour of a neuron could be copied by a
computer program, but that this artificial neuron would lack the
essential ingredient for consciousness. This claim can be refuted with
a purely analytic argument, valid independently of any empirical fact
about the brain. The argument consists in considering what you would
experience if part of your brain were replaced with artificial neurons
that are functionally equivalent but (for the purpose of the reductio)
lacking in the the essential ingredient of consciousness.


-- 
Stathis Papaioannou