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Rationally Speaking.
N. 55, November 2004
I, robot
No, this column is not about Isaac Asimov’s
famous science fiction novels concerning the interaction
between robots and humans (and even less about
the recent movie by the same title, very loosely
based on said novels). Rather, this month’s
essay has been inspired by the reading of Antonio
Damasio’s Looking for Spinoza, the third
in a series of books by this neurobiologist that
attempts to unravel the mysteries of consciousness
(the other two are Descartes’ Error and The
Feeling of What Happens).
One of the most recurring instances of anti-naturalistic
prejudice is the refusal to admit that the mind
is a result of the activity of the body; no ectoplasm
needed, as philosophers of mind put it. Few today
would reject the notion that the body itself is
very much like a machine. I was reminded of this
rather obvious conclusion during a recent trip
to the dentist: listening to a mechanical tool
working its way through my teeth in order to fix
the problem (I was having a root canal operation)
it occurred to me that there was little difference
between my predicament and a mechanic working
on my car. This is a rather novel conception of
the human body: before the work of philosopher-scientist
Rene` Descartes in the 17th century it would have
been inconceivable even for most scientists to
think of the body as a machine.
But the mind, still most people say today, is
an entirely different matter. After all, Descartes
himself stopped short of extending his reductionist
analysis to human thought (though it isn’t
at all clear weather he did so out of genuine
conviction or as an attempt to avoid the fate
of his contemporary Galileo). Yet, consider the
following instance, reported by Damasio in Looking
for Spinoza. A group of neurosurgeons at a hospital
in Paris was conducting a farly routine operation
on a patient affected by Parkinson’s disease.
The idea was that, since the woman wasn’t
responding to drug treatment anymore, the medical
equipe would go straight into her brain and stimulate
via electrodes specific regions of the brain stem.
The procedure usually yields stunning results,
which completely erase the symptoms of the disease,
greatly improving the patient’s quality of
life, at least temporarily.
In this particular instance, however, something
went wrong. When one of the electrodes was activated,
the patient suddenly stopped talking, began looking
very sad and started crying uncontrollably, eventually
explaining how her life was meaningless and she
wished to die. It is important to note that the
individual in question had never shown symptoms
of depression before the implantation of the electrode.
Even more stunningly, the talk of suicide, the
crying, and the sad expression all decreased and
then disappeared minutes after the electrode was
removed by the medical scientists! If this doesn’t
sound like a machine being turned on and off at
will by a simple electrical stimulation, I don’t
know what will convince you.
A crucial reason why Damasio is interested in
cases like the one of the French woman affected
by Parkinson’s lies in the exact sequence
of events and what it tells us about the nature
of human thought. Notice that the facial signs
of sadness appeared first, followed by the crying,
and only significantly later by the articulation
of the feeling of emptiness and despair. The same
sequence has been found in other experiments and
it suggests that feelings are generated by the
brain’s thinking about, or perceiving, the
body’s emotions. That is, emotions are simpler
physical phenomena, while feelings are more complex,
second-order, mental events.
Still not convinced that we are very sophisticated
biological machines, in both body and mind? Then
consider another fascinating example from Damasio’s
book. One of his own patients was affected by
a bizarre and rather disturbing condition, which
provides a stunning insight into the mind-body
connection. The man in question suffered occasional
episodes during which he would begin to loose
the feeling of the lower parts of his body, as
if under local anesthesia. The loss of feeling
continued gradually upwards throughout the body,
until it reached the throat, at which point the
man passed out. A similar condition affecting
a female patient did not cause her to loose consciousness,
despite the frightening experience of no longer
feeling her limbs and trunk. Tellingly, this second
patient retained a sensation of her internal organs.
Damasio suggests the intriguing possibility, based
on these and similar cases, that we have a mind
only until we have a body sensation of some sort
(even highly incomplete, as in the case of the
second patient). However, no body immediately
means no mind. What more compelling evidence could
there be that dualism is dead in its tracks?
Damasio goes further, and in his book he builds
a convincing, if circumstantial, case for the
radical idea that the mind actually is a monitoring
system of the internal and external state of our
body. The mind, then, is not a thing, but a process
(of the brain, and hence the body) by which certain
animals with complex brains keep track of and
control what their bodies are doing. We seem to
be well on our way to truly explain consciousness
as a biological phenomenon. All of this, of course,
is no reason to think that we are “just”
robots in the demeaning sense of being “mere”
machines having no intrinsic value. There is nothing
trivial or simple about the working of the human
body and mind. Moreover, human life has value
for other humans, and scientific evidence of the
kind I discussed here is meant to help us understand
how we generate, literally, our selves, not to
tell us how much we should value those selves
from an ethical perspective.
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