Sunday, 18 May 2014
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.
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:
Identity theorists believe that folk psychology “will be smoothly reduced by completed neuroscience, and its ontology preserved by dint of transtheoretic identities”.
The dualist “expects that [the mind] will prove irreducible to completed neuroscience”.
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”.
“[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!”
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.