Information Technology Reference
In-Depth Information
The response of a nerve cell does not encode the physical nature of the agents that
caused its response. Encoded is only “how much” at this point on my body, but not
“what.”
Take, for instance, a light-sensitive receptor cell in the retina, a “rod” that
absorbs the electromagnetic radiation originating from a distant source.
This absorption causes a change in the electrochemical potential in the rod,
which will ultimately give rise to a periodic electric discharge of some cells
higher up in the postretinal networks (see below, Fig. 15), with a period that
is commensurate with the intensity of the radiation absorbed, but without
a clue that it was electromagnetic radiation that caused the rod to discharge.
The same is true for any other sensory receptor, may it be the taste buds,
the touch receptors, and all the other receptors that are associated with the
sensations of smell, heat and cold, sound, and so on: They are all “blind” as
to the quality of their stimulation, responsive only as to their quantity.
Although surprising, this should not come as a surprise, for indeed “out
there” there is no light and no color, there are only electromagnetic waves;
“out there” there is no sound and no music, there are only periodic varia-
tions of the air pressure; “out there” there is no heat and no cold, there are
only moving molecules with more or less mean kinetic energy, and so on.
Finally, for sure, “out there” there is no pain.
Since the physical nature of the stimulus—its quality —is not encoded into
nervous activity, the fundamental question arises as to how does our brain
conjure up the tremendous variety of this colorful world as we experience
it any moment while awake, and sometimes in dreams while asleep. This is
the “problem of cognition,” the search for an understanding of the cogni-
tive processes.
The way in which a question is asked determines the way in which
an answer may be found. Thus it is upon me to paraphrase the “problem
of cognition” in such a way that the conceptual tools that are today at our
disposal may become fully effective. To this end let me paraphrase (Æ)
“cognition” in the following way:
cognition
Æ
computing a reality
With this I anticipate a storm of objections. First, I appear to replace one
unknown term cognition , with three other terms, two of which, computing
and reality , are even more opaque than the definiendum, and with the only
definite word used here being the indefinite article a. Moreover, the use of
the indefinite article implies the ridiculous notion of other realities besides
“the” only and one reality, our cherished Environment; and finally I seem
to suggest by “computing” that everything, from my wristwatch to the
galaxies; is merely computed, and is not “there.” Outrageous!
Let me take up these objections one by one. First, let me remove the
semantic sting that the term computing may cause in a group of women and
men who are more inclined toward the humanities than to the sciences.
Search WWH ::




Custom Search