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From: BARNARD@SRI-STRIPE.ARPA.UUCP
Newsgroups: mod.ai
Subject: perception (realist vs. representationalist position)
Message-ID: <8607141743.AA01420@>
Date: Mon, 14-Jul-86 13:09:34 EDT
Article-I.D.: .8607141743.AA01420
Posted: Mon Jul 14 13:09:34 1986
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Maybe I've never really understood the arguments of the so-called
"perceptual realists" (Gibson, etc.), because their position that we
do not build internal representations of the objects of perception,
but rather perceive the world directly (whatever that means), seems
obviously wrong.  Consider what happens when we look at a realistic
painting.  We can, at one level, see it as a painting, or we can see
it as a scene with no objective existence whatsoever.  How could this
perception possibly be interpreted as anything but an internal
representation?

In many or perhaps even all situations, the stimuli available to our
sense organs are insufficient to specify unique external objects.  The
job of perception, as opposed to mere sensation, is to complement the
stimulus information to create a fleshed-out interpretation that is
consistent both with the stimulus and with our knowledge and
expectations.  Gibson emphasized the richness of the visual stimulus,
arguing that much more information was available from it than was
generally realized.  But to go from this observation to the conclusion
that the stimulus is in all cases sufficient for perception is clearly
not justified.
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