What is experience? [Excerpts Only]
[….]
Tonini
and Koch claim that their theory successfully answers questions about nonhuman
animals, people in coma, digital computers, etc.; for example, they ascribe
consciousness to nonhuman animals, even ‘some very simple ones,’ but not to
digital computers […] Block
also contends that ‘mice or even lower animals might have phenomenal
consciousness.’ It appears that, independently of whether they adopt
functionalist or biological theories of consciousness, researchers agree on the
application of the concept of consciousness to nonhuman animals, perhaps going
down to ‘lower’ and ‘simple’ life-forms.
On the face of it, such a large
agreement on lower animals having phenomenal consciousness—along with humans—carries much physiological basis. Phenomenal
consciousness seems to be a property of organisms that marshal some or other
sensory system. As some stimulus triggers the sensory system under appropriate
‘non-anesthetic’ conditions, the organism attains a state of phenomenal
consciousness as it undergoes the stimulus-experience. So, if the organism is
endowed with receptors that detect specific colours such as orange, the
organism will undergo an orange
sensation, just as David Chalmers did […]
Let us grant, therefore, that most
organisms, by virtue of being an
organism, have or undergo experiences; when they do so, they are in a state of
phenomenal consciousness. Needless to say, all the accompanying problems of the
first person and explanatory gap continue as before. We will never know
introspectively what it feels like to be a bat even if, incredibly, we have
fully charted out that unique state
of the bat’s brain. But then, as noted, if we do have a unique chart, it is
unclear what else there is to know.
As
far as I know, the 17th century French philosopher Rene Descartes
was well acquainted with whatever was then known about the anatomy and
physiology of brains. Yet, according to standard interpretations, Descartes
insisted that only humans are conscious; all other organisms are mere automata,
machines that push and pull but don’t feel anything […] But what did Descartes
in fact say and mean? In his famous letter to Henry More, dated 5 February 1649 (Cottingham et al. 1991, 366), Descartes categorically asserted
that ‘I do not deny life to animals […] and I do not even deny
sensation, in so far as it depends on a bodily organ.’[…] Thus, Descartes kept
cognition (=thoughts) and consciousness (=sensations) strictly separate for
animals, as recommended by Block and others. However, Descartes did not keep cognition and consciousness
separate for humans; earlier in the
same letter, Descartes stated that ‘thought is included in our mode of
sensation’ (365) […]
Do animals, to whom Descartes cheerfully assigned
the property of undergoing sensations, also find
themselves absorbed in those sensations? Descartes would have answered in the
negative since, for him, animal mode of sensation does not include thought, the
thought that I am having orange sensation.
We know that humans do because humans say
so […] Several centuries later, Donald Davidson (1975) reached the same
conclusion with more sophisticated arguments: animals don’t have thoughts
because they don’t talk. It could
be that both Descartes and Davidson are using unnecessarily narrow conception
of talk and speech to exclude the animals. May be there are gentler notions of
(structured) thought that might favourably apply to some animals of sufficient
neural complexity […]
The basic
issue is not whether the notions of experience and phenomenal consciousness
legitimately apply to nonhuman animals. The Cartesian point is that these
notions legitimately apply to thoughtful modes of sensation. Since a sensation,
by definition, pertains to individual organisms, a thought of that sensation can only be a
first-person thought marked by the use of the pronoun I or its equivalent. This roundabout way of bringing out the
Cartesian point basically means that an organism needs to have the concept of sensation, experience,
consciousness, and the like to find
that something is going on; otherwise, something just goes on. Strictly
speaking, undergoing an orange sensation is not an experience, finding oneself
so undergoing is. Obviously, what one
finds is not the heightened state of
the brain, but the resulting feel […]
Is the feel
entirely a fiction? I am unsure what the answer is. I just said that the
subject does not have introspective access to the state of the biological
system while undergoing a specific orange sensation. That seems to be the typical case. But it does not rule out
the possibility that, on occasion, subjects may even have introspective access
to the brain itself. We do have introspective access to states of other organs
such as heart and stomach, not to mention the obvious case of genitals. Anecdotally,
I can report that, on several occasions during particular phases of high fever,
it appears as if the brain itself is the object of experience. While one is
still fully awake, one is unable to focus on any specific object of thought
through standard perceptual means due to high fever; in fact it is difficult to
keep one’s eyes open. Yet there seems to be the experience of a dark void
pulsating in the head; it is very different from even crushing headaches felt
in localised areas. […]
The shift of
talk, as above, from visual experience to painful experience could be an
indicator of how the fiction arises. We genuinely report feels when in pain
because we have at least partial introspective access to the state of the body.
In those cases, the conception of the feel could be viewed as a response of the
body itself to some (injured) state of the body. That is why when we are in
(physical) pain, we visit the doctor, not the psychologist, without taking a
stand on dualism. However, talk of feel when looking at my computer screen
sounds a bit odd, unless the screen is glowing or something such that it hurts
[…]
To sum up,
the concept of phenomenal consciousness seems to have a variety of conflicting
pulls. In some form or other, phenomenal consciousness is inevitable for
organisms with developed sensory systems. The first problem is with its
inherently first-person character. It arises because the occurrences of
experiences are subjective in the sense outlined. When we try to overcome this
problem with, say, a (third person) biological story that correlates a unique
state of the brain with occasions for subjective experiencial states, an
explanatory gap shows up. Since the problem sounds more empirical than
conceptual, suppose the gap is somehow bridged in some future science, perhaps
in the form of a complete description of the underlying biological system.
Even then it
appears that the purported biological explanation will have the wrong grain
because the first-person states are the states of a subject as a person, rather
than the states of the subject’s brain. Keeping exclusively to subject’s
reports, it is also extremely unclear what the report of experiences are about once we have de-linked those
reports from the unique brain-states correlated with those experiences. In
fact, in some cases, it would seem that the reports are about nothing, the
‘feel’ involved in experiences could be fictions. Yet, and this is the
near-fatal point, the talk of
experiences just cannot be given up or eliminated because the talk simply
reflects the structured thought that is included
in subjective experiences, at least in the human case. […]
(To be continued)
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