These are excerpts and elaborations from my book "The Nature of Consciousness"
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Cognitive Closure The British philosopher
Colin McGinn argued that consciousness cannot be understood by beings with
minds like ours. McGinn believes that there is nothing "magic" about
consciousness: consciousness is a natural phenomenon just like many others
(lightning or hurricanes or comets) and, as such, it is a consequence of the
way matter is structured and functions (specifically, how the brain
works). We are capable of
understanding natural phenomena like lightning and hurricanes, but McGinn suspects that we are not
capable of understanding "all" natural phenomena. There are natural
phenomena that our mind cannot comprehend, just because our mind is not an
infinitely powerful computer. In a sense, McGinn’s central thesis is that our mind has limitations. Consciousness
itself might be one of the phenomena that fall within the mind's limitations,
i.e. fall outside the "cognitive closure" of the human mind. That
does not mean that nobody can ever explain consciousness: a being equipped with
a "better" mind could understand how consciousness works, where it
comes from and what it is. But not our mind. We can understand how the
brain works. The brain is a natural phenomenon that we can easily investigate
with our science. We will learn more and more about the brain. We will
eventually work out a very detailed model of the brain. We may even be able to reproduce the brain
molecule by molecule. But we will never
be able to figure out how emotions arise from the unconscious matter that makes
up the brain. McGinn’s fundamental assumption is that the human mind is biased in its
cognitive skills. This follows from a Darwinian view of life: all of our organs
are biased, one way or another, towards coping with the environment. McGinn simply
extends this principle to the mind. Our mind is very skilled at understanding
spatial and temporal relationships, and at doing what we call Science. Our mind
is probably not very skilled at doing things that would be useful on Mars but
that do not exist on Earth. Thus it is reasonable to assume that the human mind
has been designed by evolution to solve some problems better than others, and
not to solve many other problems at all. In particular, McGinn thinks that our intelligence is
not designed to understand consciousness. Science is the systematic
understanding of nature by the human mind, but it is limited to what the human
mind can understand. There might be many things in nature that the human mind
will never understand, and maybe not even perceive. Consciousness is one of
them. Our brains were not biologically designed to understand consciousness.
McGinn even speculates that knowledge of ourselves is useful to a limit: maybe
if we could fully understand ourselves, we would get very depressed and not
willing to survive anymore. Thus natural selection may have pruned away the
ones who did understand consciousness, and left only the ones who could not
understand it, of whom we are the descendants. Inspired partly by the
British philosopher Bertrand Russell and partly by the German
philosopher Immanuel Kant, McGinn argues that consciousness is
known by the faculty of introspection, as opposed to the physical world, which
is known by the faculty of perception. The relationship between one and the
other, which is the relationship between consciousness and brain, is
"noumenal", or impossible to understand: it is provided by a lower
level of consciousness that is not accessible to introspection. That is why
consciousness does not belong to the "cognitive closure" of the human
organism. Understanding our consciousness is beyond our
cognitive capacities, just like a child cannot grasp social concepts or i
cannot relate to a farmer's fear of tornadoes. McGinn points out that other creatures in nature
lack the capacity to understand things that we understand (for example, the
general theory of relativity). There are parts of nature that they cannot
understand. We are also creatures of
nature, and there is no reason to exclude that we also lack the capacity to
understand something of nature. We may
not have the power to understand everything, unlike what we often assume. Some
explanations (such as where the universe comes from, and what will happen
afterwards, and what is time and so forth) may just be beyond our mind's
capacity. Explanations for these phenomena may just be "cognitively
closed" to us. Phenomenal consciousness may be one such phenomenon. "Mind may just not be big
enough to understand mind". McGinn speculates that consciousness might be a very
ancient invention. Indeed, the fact that consciousness has no spatial
dimensions leads him to speculate that consciousness may have tapped into a
non-spatial property that disappeared with the Big Bang (the cosmic event that
created the spatial universe we live in). Our minds may be remnants of a
dimension that does not exist anymore but that was pervasive in the pre-Big
Bang universe. He cunningly refutes the
idea that computers can be conscious in virtue of being computers. McGinn explains that this idea is
based on a bad theory of consciousness.
We have no evidence that the property of running a program is the
property that yields consciousness. This does not mean that conscious machines
are impossible: the key is in finding out what is the property that yields
consciousness, and then implementing that feature in a machine. McGinn points
out that one such machine already exists: me. Thus it is feasible. Cogito, ergo
I am feasible. McGinn changes the question to make it more interesting: can a
machine made of inorganic material be conscious? Implicitly, McGinn assumes that our “cognitive
closure” does not change with time, that it is a constant of the human
condition. On the other hand, it is obvious that it changes during the course
of a lifetime: children cannot grasp concepts that adults can. One can also
argue that our “cognitive closure” has evolved over the centuries, that we are
more “conscious” today than we were thousands of years ago. Certainly, concepts
such as democracy and women’s rights are more obvious to today’s humans than
they were to even the most enlightened of the ancient Greek philosophers.
Studies on ancient texts point to a reliance on gods that today has been
replaced by a reliance on our own opinions. One can argue that today we “think”
differently. One can argue that each generation uses knowledge from the
previous generation to expand that “cognitive closure”. The question then is whether
the “cognitive closure” that McGinn talks about is a temporary
limitation, a “stage” in the evolution of manking, or a permanent deficiency of
our mind (due, say, to the structure of the brain, or to some impossible neural
connections, or to the limited capacity of our memory). Since McGinn does not
“quantify” where the cognitive closure comes from, i.e. what it is physically,
one cannot decide whether it can be overcome or not by future generations. If we
do not know what causes that cognitive closure, we cannot know whether it can
be overcome. The Kenyan-born biologist
Richard Dawkins, following the British
biologist John Haldane, believes that, just like
there are limits to what human eyes can see because they only see what made
sense to evolve over millions of years, there is no reason to believe that
evolution shaped the human brain to perform any more function than what is
needed to survive in its environment. For example, we can only see in black and
white mode at night, and we don’t see (nor hear) the extreme parts of the
spectrum of frequencies. If that is true for the eyes, it is likely to be true
also for the brain: the human brain evolved the ability to “think” what matters
for the survival of humans, but not the ability to “think” other thoughts,
which are therefore beyond the ability of the human brain. Just like we cannot
run as fast as a cheetah, we cannot think as profoundly as some other being that
(who?) has evolved or will evolve a better kind of brain. Nonetheless, one can object:
if our brains were not designed to understand consciousness, why are we
wondering about it? Were our brains designed to wonder about consciousness?
Were our brains designed to wonder about something that we cannot possibly
understand? Why? Back to the beginning of the chapter "Consciousness: the Factory of Illusions" | Back to the index of all chapters |
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