Historically,
or I should say in the fairly recent past, there have been many
arguments offered against materialism in the mind and matter debate.
Philosophers have posited mental phenomena that were supposed to be
irreducible to matter (or the brain). Churchland himself offers us
four examples: emotions, qualia, raw feels and now - Churchland was
writing in 1980 - propositional attitudes. Such things were/are
proposed to be both ineliminable and irreducible. Churchland was
saying that the goal posts kept on shifting to make way for an
irreducible or ineliminable mind (or aspects thereof).
Churchland
said that the resistance eliminative materialism encounters surprises
him. “After all,” he said, “common sense has yielded up many
theories.” Here the reader can fill in his own examples rather than
relying on the many that Churchland offers.
Propositional Attitudes
Why
are we so absolutely certain that our minds contain propositional
attitudes (e.g., beliefs and desires)? Could we possibly make a
mistake about the workings of our own minds? Churchland thinks that
we can. Many people think that although we can make mistakes,
sometimes big ones, about the external world, the same is not true
about the internal world (the mind). But the reasons for making
mistakes about the external world are pretty similar to those that
can be applied to the mind or the mental. An “introspective
judgment” is a “conceptual response to one’s internal states”.
So just as we rely on contingent and possibly false concepts to
acquire a picture of the external world, similar conceptual schemes
are brought to bear on our introspective judgments. The mind is not
transparent (as
Descartes and others have thought). So the judgments we make about
the workings of our own minds are “always contingent on the
integrity of the acquired conceptual framework (theory) in which the
response is framed”. We look through, as it were, contingent and
possibly false concepts when we introspect. But what has all this to
do with the existence or non-existence of propositional attitudes
(which is Churchland’s primary concern)? The answer to this is
simple: we may be wrong about our minds being the “seat of beliefs
and desires”. That is, beliefs and desires as
we know them may not exist. Indeed, a belief
in beliefs and desires may be as misplaced, according to Churchland,
as the ancient belief that the “star-flecked sphere of the heavens
turns daily”.
But
let’s be clear about the folk psychologist’s position is on the
reality of propositional attitudes. The things we believe and desire,
or, more correctly, the propositional content of our beliefs and
desires, are effectively quantified over by the folk psychologist.
Not only that, but he sees that the relations (e.g., entailment,
equivalence and mutual inconsistency) between beliefs and desires and
other beliefs and desires are “lawlike”. So all this sounds very
much like a scientific theory, despite the fact that we are talking
about the mental. And that’s why folk psychology is a theory.
Churchland goes into more detail about the theoretical status of folk
psychology.
If
folk psychology is a theory, it wasn’t thought to be one until the
second half of the twentieth century. Churchland thinks that it’s a
mystery why the theoretical nature of folk psychology was never
recognised, especially bearing in mind that he thinks that it is “so
obviously a theory”.
Churchland then goes onto compare folk psychology with the theories
of mathematical physics. He finds very interesting parallels. But
whereas mathematical physics has a domain of numbers to quantify
over, folk psychology quantifies over the domain of propositional
attitudes.
There
are many options on reduction and ineliminativity to be taken in the
philosophy of mind. Apart from his own, Churchland cites three
alternatives: the identity theory, dualism and functionalism. He
summarises them thus:
The Identity Theory
Identity
theorists believe that folk psychology “will be smoothly reduced
by completed neuroscience, and its ontology preserved by dint of
transtheoretic identities”.
Dualism
The
dualist “expects that [the mind] will prove irreducible
to completed neuroscience”.
Functionalism
The
functionalist also “expects that [the mind] will prove irreducible…
[because] the internal economy characterised by folk psychology is
not…a law-governed economy of natural states, but an abstract
organisation of functional states, an organisation instantiable in a
variety of quite different material substrates”.
Churchland
happily concedes that FP enjoys a “substantial amount of
explanatory and predictive success”. And then concludes: “And
what better grounds than this for confidence in the integrity of its
categories?” Of course, Churchland is being rhetorical here. He
doesn’t believe that its explanatory and predictive successes are
in fact, after 2,000 years of its hegemony, that great. He then gives
a list of its notable failures. He says:
“…consider
the nature and dynamics of mental illness, the faculty of creative
imagination…Consider our utter ignorance of the nature and
psychological functions of sleep….Or consider the miracle of
memory, with its lightning capacity for relevant retrieval.”
Folk
psychology offers virtually no insights on all the above. It is
explanatorily and predictively more or less useless. And the main
reason for this, as Churchland perceives it, is how the folk
psychologist explains the mechanisms of thought. The folk
psychologist sees learning “as the manipulation and storage of
propositional attitudes”. That is, within the mind-brain there are
sentences or propositions of some kind, or possible analogues of
sentences or propositions. It is a thoroughly sentential or
propositional approach to learning and thought. But, Churchland
argues, something must have predated the storage and manipulation of
propositional attitudes. Propositional attitudes couldn’t have
shown us how to manipulate propositional attitudes before such they
were on the scene. So certain non-propositional mechanisms must have
predated the storage and manipulation of propositional attitudes. He
says that it “is only one among many acquired cognitive skills”
and therefore FP faces “special difficulties”.
Beyond Folk Psychology
So what precisely is Churchland alternative to FP? What does he believe are the mechanism of thought, learning, etc? For a start, his descriptions could be called “scientistic” (I am using that term in a non-judgemental way). He relies heavily on the findings of neuroscience and rejects any a priori philosophising. So I will describe in full his very non-linguistic and non-logical (possibly non-philosophical!) account of mind-brain activity:
“[The
neuroscientific theory] ascribes to us, at any given time, a set or
configuration of complex states, which are specified…as figurative
‘solids’ within a four- or five-dimensional phase space.”
Clearly
there is no mention of logical relations, propositions, beliefs,
desires and all the rest. This is essentially the language of
neuroscience rather than the language of philosophy. Having said
that, these descriptions of brain activity are not necessarily the
result, or entirely the result, of research into the nature of the
brain. It is a theory
after all. So there is as much speculation here as one would find in
any philosophical theory. The difference being that the landscape
described and terms used are those of neuroscience and not of
philosophy. The brain, according to this theory, has read the book of
science, and not the book of language and logic.
The
mental states that FP postulates are simply not law-governed. It is
this that Churchland has a major problem with. It essentially takes
FP outside the realm of science and into Kantian world of noumenol
freedom. More precisely, propositional attitudes and their relations
are not law-governed. Kinematical states and configurations, on the
other hand, are
law-governed.
There
is an alternative to propositional or sentential language. Just as we
are familiar with the language of propositional attitudes and their
relations, we could become familiar with kinematical states and their
relations and interactions. We could “acquire a vocabulary” that
could “characterise our kinematical states”. And, of course,
these law-governed relations and interactions would be scientifically
bona fide. We could also learn how these kinematical states cause
behaviour. We would therefore be able to predict behaviour to a
higher degree than we do now. More to the point, if we could
literally read the brain, we would have first-person access to other
mind-brains!
Churchland
clearly thinks that philosophers of mind, and philosophers generally,
have over-stressed the importance of language when it comes to
mentality (and have also, incidentally, lingui-fied and logi-fied the
mind itself). (See quote from dynamics paper.) Churchland claims that
natural languages “exploit only a very elementary portion of the
available machinery, the bulk of which serves far more complex
activities beyond the ken of the propositional conceptions of FP”.
It is of course very hard to accept that natural languages have been
over-stressed, considering the importance of them in the lives of
virtually all human beings. But there are other mental activities
that are just or more important, it’s just that philosophers,
because of their linguistic or logical bias, haven’t really
registered them. These alternatives can even be deemed forms of
language, according to Churchland. Though their makeup is very
different. Their syntactic and semantic structures could be
“decidedly alien”. However, these non-natural languages, as it
were, “could also be learned and used by our innate systems”.
This new language, or these new languages, would have a “new and
more powerful combinatorial grammar over novel elements forming novel
combinations with exotic properties”. But because they are not
propositional,
or even statemental, they could not be evaluated as true or false.
Nor could the relations between these elements be “remotely
analogous to the relations of entailment, etc. that hold between
sentence”.
In
order to demonstrate his position Churchland basically says that such
a non-natural language already exists in the brains of human beings.
He tells us that the left hemisphere of the brain does communicate
with the right hemisphere (and vice versa). And, of course, this
communication is non-propositional. So if two parts of the same brain
can communicate so effectively without propositional forms, then why
can’t two brains? Between the two hemispheres of a single brain is
what is called the “commissure”. The commissure carries the
messages from one hemisphere to the other. It is a kind of bridge
between the two. So in order for two separate brains to communicate
non-propositionally with each other, we would need to construct an
artificial commissure. But we would need more than an artificial
commissure to ensure communication between two brains. This is how it
could work out, according to Churchland. We would need to implant a
transducer in both brains. This transducer would “convert a
symphony of neural activity into (say) microwaves radiated from an
aerial in the forehead”. This would run through the artificial
commissure and enter the recipient brain. And, alternatively, rather
than neural activity being converted into microwaves, we would also
need to convert microwaves back into neural activity. That is, the
information-receiving
brain would require this.
And
if two brains can communicate in such a manner, why not three or even
more? Such are group of artificially connected people could “learn
to exchange information and coordinate their behaviour [like their]
own cerebral hemispheres”. One result of this, that is, of brains
communicating directly with brains, is that “spoken language of any
kind might well disappear completely”. Also, in library books we
wouldn’t find words and sentences but “long recordings of
exemplary bouts of neural activity”. In essence, we would be
reading the neurophysiological goings on of other people’s brains.
Of course, we would initially need a translation manual from the
brain states to our understanding of the brain states. However, if we
don’t need a translation manual to understand our own cerebral
activities, perhaps we wouldn’t need one to understand other
people’s brain workings.
People
will of course ask: “How will such people understand and conceive
of other individuals?” And Churchland answers his own question by
saying: “In much the same fashion that your right hemisphere
‘understands’ and ‘conceives of’ your left hemisphere –
intimately and efficiently, but not propositionally!”
Is Eliminative Materialism Self-Contradictory?
There
is a well-known argument offered against elimitivist materialism. It
revolves around its self-contradictory or incoherent nature. The
argument is this. Because eliminative materialists are not meant to
believe in propositional attitudes (like belief, intention and
knowledge), then their statements in favour of eliminative
materialism are “just a meaningless string of marks or noises”.
Why is this so? Because they believe
in what they say. And they have an intention
to communicate. And they have knowledge
“of the grammar of the language” and knowledge
of the ‘truths’ of their own findings. But belief, intention and
knowledge are deemed to be propositional attitudes, and eliminative
materialists don’t believe in these things. Here’s the
self-contradictory bit. If the statement of eliminative materialism
is true, then it is false. It is false because there are no beliefs
or knowledge to express, according to its own doctrine. According to
itself, the primary statement of eliminative materialism is a
“meaningless string of marks or noises” because it cannot be a
belief (true or false) and it can’t be knowledge because these
things are propositional attitudes. It therefore can’t be true by
its own standards. As Churchland himself says: “Therefore it is not
true. Q. E. D.”
Patricia
Churchland offered a riposte to these ‘refutations’ of
eliminative materialism, which Paul Churchland quotes in full.
Firstly he offers a psychological rather than philosophical argument.
That is, EM is just so radical, revolutionary and, perhaps, in
initially counterintuitive, that it is understandable that people
react fiercely to it. Churchland finds an historical parallel with
eliminative materialism. It revolves around the reaction against
vitalism. It was once held that when a vital spirit inhabited
inanimate matter, it would become animate (alive). This belief in
vital spirits was shared by just about everyone at certain points in
history. It was “integrated with many of our conceptions”. So if
anyone were to reject vitalism, which they did, the “magnitude of
the revisions any serious alternative conception would require”
would have encouraged just about everyone, at first, to fiercely
reject anti-vitalism (this in fact happened). So, according to
Patricia Churchland, the vitalist could have, and perhaps did, offer
arguments the anti-vitalist that would be very much like the
arguments the anti-eliminativist offers against the eliminativist.
This is how it goes:
“The
anti-vitalist [eliminativist] says that there is no such thing as
vital spirit [propositional attitudes]. But this claim is
self-refuting. The speaker can expect to be taken seriously only if
his claim cannot. For if the claim is true, then the speaker does not
have vital spirit [propositional attitudes] and must be dead
[contradicting himself]. But if he is dead [or
lacks propositional attitudes], then his statement is a meaningless
string of noises, devoid of reason and truth.”
So
the antagonist says that the eliminative materialist can only be
saying something true if he agrees with him. This effectively means
that the eliminativist can only speak the truth about propositional
attitudes if he doesn’t believe what he says is the case.
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