2.6 Biological Realism
1. Studying Natures Examples?
Hopefully by now you have noticed that one of the recurring themes that keeps popping up in the
philosophy of the mind is the belief that the brain is not important to the study of the mind.
Dualists believed the brain was simply some kind of interface to the mind spirit. Behaviorists
believed that the mind did not even exist, and behaviors and tendency to behavior are the only
things there are. Functionalists believe that it is only the input-output relations that are
important, and that the structure these relations are implemented in is of no consequence.
And Connectionists say they believe the structure is important to the function of the brain,
but then go right on to ignore even the most basic principles of neurobiology. I find this
all truly astonishing. Imagine if I were to go to an engineer with an alien device that could produce antigravity
fields and told him he had to learn how it worked, but he was forbidden to take the device apart
to study it. Instead, he was only allowed to tinker with a few of the control buttons on the outside
to see what actions they produced, and from that alone he had to construct a working theory
of how the device operated. He would laugh in my face! And rightly so. It is very simple. We will
never understand how the mind works without studying, in detail, the working examples that nature
has provided us. Or as Francis Crick, the co-discoverer of the structure
of DNA, puts it:
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Jackendoff and Johnson-Laird are both functionalists. Just as it is not necessary to
know about the actual wiring of a computer when writing programs for it, so a functionalist
investigates the information processed by the brain, and the computational processes the
brain performs on this information, without considering the neurological implementation of
these processes. He usually regards such considerations as totally irrelevant or, at best,
premature.
This attitude does not help when one wants to discover the workings of an immensely
complicated apparatus like the brain. Why not look inside the black box and observe how its
components behave? It is not sensible to tackle a very difficult problem with one hand tied
behind one's back. When, eventually, we know in some detail how the brain works, then a high-level
description (which is what functionalism is) may be a useful way to think about its overall
behavior.
(Crick, The Astonishing Hypothesis)2.6.1
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2. Its All In the Vocabulary.
How did we come to this pass where so many incredibly intelligent people can say and believe things
that are obviously ludicrous? John Searle has a theory about how this all came about, and it makes
a good deal of sense to me. He believes that all of these problems are due to the fact that even though
Cartesian dualism is totally shunned in the scientific world, we are all still using the basic assumptions
and vocabulary of dualism.
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But the unconscious motivation for all of this, the motivation that never somehow manages
to surface, is the assumption that materialism is necessarily inconsistent with the reality
and causal efficacy of consciousness, subjectivity, etc. That is, the basic assumption behind
materialism is essentially the Cartesian assumption that materialism implies antimaterialism.
There is something immensely depressing about this whole history because it all seems so pointless
and unnecessary. It is all based on the false assumption that the view of reality as entirely physical
is inconsistent with the view that the world really contains subjective ("qualitative," "private,"
"touchy-feely," "immaterial," "nonphysical") conscious states such as thoughts
and feelings.
The weird feature about this entire discussion is that materialism inherits the worst assumption of dualism.
In denying the dualist's claim that there are two kinds of substances in the world or in denying the
property dualist's claim that there are two kinds of properties in the world, materialism inadvertently
accepts the categories and vocabulary of dualism. It accepts the terms in which Descartes set the debate.
It accepts, in short, the idea that the vocabulary of the mental and the physical, of material and immaterial,
of mind and body, is perfectly adequate as it stands. It accepts the idea that if we think consciousness
exists we are accepting dualism. What I believe-as is obvious from this entire discussion-is that
the vocabulary, and the accompanying categories, are the source of our deepest philosophical difficulties.
As long as we use words like "materialism," we are almost invariably forced to suppose that
they imply something inconsistent with naive mentalism. I have been urging that in this case,
one can have one's cake and eat it too. One can be a "thoroughgoing materialist"
and not in any way deny the existence of (subjective, internal, intrinsic, often conscious)
mental phenomena.
(Searle, The Rediscovery of the mind)2.6.2
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3. The Emergent Mind.
If we do not accept the old vocabulary, then how is it possible for the "non-physical"
mind to come from a completely materialist universe? The answer is that the mind is simply
an emergent processes that arises because of the highly complex, and non-linear
interactions of billions of interconnected neurons.
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Consciousness is a higher-level or emergent property of the brain in the utterly
harmless sense of "higher-level" or "emergent" in which
solidity is a higher-level emergent property of H2O molecules when they
are in a lattice structure (ice), and liquidity is similarly a higher-level emergent
property of H2O molecules when they are, roughly speaking, rolling around
on each other (water). Consciousness is a mental, and therefore physical, property of
the brain in the sense in which liquidity is a property of systems of molecules.
If there is one thesis that I would like to get across in this discussion it
is simply this: The fact that a feature is mental does not imply that it is not
physical; the fact that a feature is physical does not imply that it is not mental.
(Searle, The Rediscovery of the mind)2.6.3
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However, it is almost impossible to see this with the old vocabulary because by-definition materialist
implies a separation between the physical world and mental phenomenon. It is this assumption that
Searle is trying to make us overcome. He is not adhering to property dualism here. He
is not saying that the mental is separate property that is non-physical. He is saying it is a physical
process of our physical brains. When you put your hand on a table it hits the surface and then stops.
You hand does not just continue to go through the wood of the table. This is because of the higher-level
interaction of the billions of atoms in the wood. They have a charge which repels the atoms in your hand
at a very low level and keeps it from going any further. These types of properties only emerge when you
get a lot of atoms or molecules together. You can not pick out one water molecule and say
"this one is wet!" Wetness is caused by billions of water molecules
acting together. Just as the mind is caused by billions of neurons acting together.
4. Conclusion.
Searle goes on to discuss a number of other topics related to this dealing with intentionality, qualia,
and subjectivity. These are important items to think about, but I feel the most important
concepts of biological realism are the ones discussed above. I do not completely agree with
everything Searle has written, and even the stuff I do agree with still needs to be proven
scientifically. But I do feel that his ideas are at least on the right track.
Before you can come up with higher-level functional descriptions of the mind, you must have
a much better understanding of how the mind emerges from the structure of the brain.
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