Saturday 4 September 2021

Eliminative Materialism: Paul and Patricia Churchlands’ Strong Neuronal Activations For Each Other


 

“One can’t help wondering whether the Churchlands’ early courtship involved poetry expressing the strength of their neuronal activations for each other.” — Professor Philip Goff (in his book Galileo’s Error)

i) Introduction: Philip Goff on the Churchlands
ii) The Future of Mind
iii) Those Damn Propositional Attitudes!
iv) Reductionism or Eliminativism?
v) Paul Churchland Believes That the Mind Exists
vi) Mental Contents and Their Expressions
vii) Problems With Eliminative Materialism
viii) Conclusion

Introduction: Philip Goff on the Churchlands

Professor Philip Goff (who’s a well known advocate of panpsychism) tells us a joke (though it’s possible that it wasn’t meant as a joke) about Paul and Patricia Churchland and their general materialist position on the mind. He writes:

“One can’t help wondering whether the Churchlands’ early courtship involved poetry expressing the strength of their neuronal activations for each other.”

Of course Paul and Patricia Churchland wouldn’t have used such neurobiological technical terms when they courted. And no one would use such a vocabulary today. That’s partly because it can be said that eliminative materialism (the position that Paul and Patricia Churchland advance) is a kind of philosophical (as it were) futurism in that it’s a position that predicts what form future scientific theories will take. That is, the Churchlands believe that the sciences will — or perhaps may — one day reveal that the mental states we refer to every day (i.e., when we use words like “love”, “believe”, “desire”) do not refer to anything real.

So what about the future?

This is how the Canadian philosopher Paul Churchland (1942- ) himself states his desire for a new language of mind:

“Neuroscience may appear to be defective in providing a purely ‘third-person account’ of mind, but only familiarity of idiom and spontaneity of conceptual response are required to make it a ‘first-person account’ as well. But it is entirely possible for a person or culture to learn and use some other framework in that role, the framework of cognitive neuroscience, perhaps.”

So is Philip Goff ruling out a change in vocabulary (as philosophers put it) a priori? And if he is, then why is he doing so?

After all, it’s a contingent fact that we use the terms we do to refer to our mental lives. Of course it can be argued that the words we use about our mental lives are somehow hardwired into our brains. But is that really the case? Are there natural-language cognates of all the contemporary terms of Western folk psychology which date back, say, 20,000 years? (The first human languages are thought to have begun between 50,000 and 150,000 years ago.) And have such terms (when translated into other languages) really been used by all other cultures too?

Despite those questions, even if such terms have been the norm throughout all histories and all cultures, then that surely still doesn’t — of necessity — stop us from acquiring a different way of speaking about the mind.

More specifically, surely Philip Goff can’t be arguing that all the expressions of (in his example) love can’t — by definition — be expressed in terms of what he calls “neuronal activations”. Indeed what’s so special about the words and concepts we currently use?

Yet, ironically enough, Goff himself unwittingly provides Paul Churchland with just the kind of argument he may well use himself. It just so happens that Goff (in this case) is talking about dualism, not love (or, for that matter, beliefs, desires, etc.). Goff writes:

“The psychologist Paul Bloom has argued that dualist thought is hardwired into use and that from an early age children categorize ‘mental things’ as distinct from ‘physical things.’”

More relevantly, Goff immediately continues with these words:

“Just because a view comes to us naturally or is hardwired, it doesn’t mean it’s true [].”

Goff’s joke is also almost like a version of the (as it were) self-refuting argument against eliminative materialism. This argument has it that because eliminative materialists use words like “belief” and “true” (or they simply believe that eliminative materialism is true), then this is evidently self-refuting. And that’s simply because, according to eliminative materialism, such things as truth and belief don’t exist. (This is covered later when Quine raises the question as to whether eliminative materialism expresses various mental states in neurobiological terms or whether it eliminates them tout court.)

Of course Paul and Patricia Churchland have offered ripostes against this argument. And Michael Devitt, for example, has offered a “deflationary” account of “x is true” that may help eliminative materialism.

Similarly (or at least fairly so), the serious part of Goff’s joke may be that in order for Paul and Patricia Churchland to be consistent about their belief in eliminative materialism, then when they courted, they should have used various words or terms from neurobiology to express their love for one another.

The Future of Mind

Paul Churchland goes into more detail on his own futurism in the following:

“Given a deep and practiced familiarity with the developing idioms of cognitive neurobiology, we might learn to discriminate by introspection the coding vectors in our internal axonal pathways, the activation patterns across salient neural populations, and myriad other things besides.”

Of course at present it would be virtually impossible (even for a neuroscientist) to describe our (to use Churchland’s own term) “first-person” thoughts, feelings and beliefs in terms of “coding vectors in our internal axonal pathways”, “activation patters across salient neural populations”, etc. It may even be hard to imagine such a state of affairs at present.

Yet Churchland wasn’t talking about the case as it is today. He explicitly stated that

“it is entirely possible for a person or culture to learn and use some other framework in that role”.

Clearly this is a statement about the future. In other words, this isn’t about a elite of neuroscientists imposing a new language on the populace today — or even next year. (Or such an elite banning all the words from folk psychology.) That said, if the “language” of folk psychology has been with us since human language itself began, then perhaps Churchland’s wishes for the future may be a little utopian. (Or, depending on one’s views, dystopian.) After all, there’s surely a difference between picking up new words or terms (which happens all the time) and picking up a new language to talk about ours minds. However, this clearly isn’t something that won’t — or can’t — happen in the future.

Those Damn Propositional Attitudes!

The following passage is a take on Paul Churchland’s general position on mind as expressed by Tadeusz Zawidzk:

“Churchland is famous for for championing the thesis that our everyday, common-sense, ‘folk’ psychology, which seeks to explain human behavior in terms of the beliefs and desires of agents, is actually a deeply flawed theory that must be eliminated in favor of a mature cognitive neuroscience.”

The main problem — so Churchland believes — with beliefs, desires, etc. is that they’re (deemed to be) propositional attitudes. And the main problem with propositional attitudes is that they (are seen to) have semantic and syntactic properties. Yet such semantic and syntactic properties can’t be translated into what goes on in the brain. Instead, what we really have are spiking frequencies, action potentials and other (neuroscientific) things. And these things, moreover, are distributed and continuous in nature, not precisely located in the brain or discrete.

Of course some philosophers have retorted that these mental states needn’t be seen as being linguistic in nature.

To take just one example. Many connectionist models of the brain do make use of what’s called representations (see here). Yet these (quasi?)representations are instantiated in the brain in a parallel and distributed manner (see here).

Reductionism or Eliminativism?

The important point now is to distinguish eliminative materialism from reductionism in the philosophy of mind.

Paul Churchland believes that “folk” concepts shouldn't be reduced to something neurobiological or scientifically kosher: he believes that they should be eliminated.

Why is that?

It’s because he believes that they don’t correspond to anything (to use a philosophical term) real or objective — that is, to anything in the brain.

Of course if beliefs, desires and the other propositional attitudes don’t exist in the first place, then it doesn’t really make sense to argue that they can be expressed in other ways. And, a few decades ago, the American philosopher W.V.O. Quine (1908–2000) made this point. He wrote:

“Is physicalism a repudiation of mental objects after all, or a theory of them? Does it repudiate the mental state of pain or anger in favor of its physical concomitant, or does it identify the mental state with a state of the physical organism (and so a state of the physical organism with the mental state)?”

So this can be expressed in the following way: either beliefs, desires, etc. exist and they’ll ultimately be explained in neurobiological terms — or they don’t exist at all and therefore they can’t be expressed in any way.

That said, Churchland would simply argue that it isn’t beliefs, desires, etc. that are being expressed with our Folk words or concepts — that’s if these things are seen as “sentences in the head”. And therefore it isn’t our beliefs, desires, etc. that are — or will be - expressed in neurobiological terms either.

So all this becomes a little circular.

Paul Churchland Believes That the Mind Exists

Despite all the above, one point that’s worth making is that Paul Churchland’s position isn’t as extreme as some people (not least Philip Goff) paint it.

Firstly, Churchland accepts that reality of the mind. Or, at the very least, he uses the word “mind”. (After all, Churchland may want to substitute or eliminate that word too.) More specifically, the mind itself (as such) isn’t denied. Instead Churchland's eliminativism is a position which states that that certain types of mental states (mainly propositional attitudes) do not exist.

Now can we even have a mind without such mental states?

That said, when it comes to consciousness (i.e., not the mind), Churchland (in his book The Engine of Reason, The Seat of the Soul) did argue that consciousness may — in the future — be explained entirely in terms of neurobiology — i.e., physical events in the brain, biochemicals, parts of the brain, etc.

Yet here again (as with beliefs, desires, etc. earlier) the following can be asked:

Is it the case that consciousness does in fact exist but that it can be — or must be — described (or expressed) in terms of neurobiology?

Or alternatively:

Is it that consciousness simply doesn’t exist at all and all we need are neurobiological descriptions of people’s brains?

Churchland also accepts that there is such thing as a “first-person account” of (my own two words) inner processes. And he even uses the word “introspection”. It’s just that Churchland also believes that these processes should be described in the language of neuroscience or cognitive neurobiology, not in the language of folk psychology. In these cases at least, then, we don’t really seem to have any eliminations at all. Perhaps that’s mainly because Churchland has focussed primarily on the propositional attitudes when it comes to his eliminativism (though recall the earlier comments on his position on consciousness itself.)

(The words “inner processes above are italicised because traditional behaviourists would never have been happy with any mention of them — and, arguably, Daniel Dennett still isn’t.)

Mental Content and its Expression

Paul Churchland also stated the following:

“What makes an account a ‘first-person account’ is not the content of that account, but the fact that one has learned to use it as the vehicle of spontaneous conceptualization in introspection and self-description.”

I don’t entirely understand Churchland's phraseology when he writes “is not the content of that account”. That said, his words may simply mean that we can make a distinction between (mental) “content” and the way we express that content. That is, there are things which occur in the mind regardless of the specific and contingent natural-language words we use to express them. (This is similar to the point philosophers have made — since Gottlob Frege here — about a single abstract proposition which can be expressed by many natural-language sentences.) In other words, we’ve acquired the words/terms of folk psychology to talk about (mental) content in our “first-person account[s]”. So we could, in the future, use the terms of neurobiology — instead — to express that very same content. (Or at least similar content as it’s “found” in the future.)

So the fact that we use words like “belief” and even “love” — and have the concepts belief and love — is a contingent fact about how we express such mental content. Indeed such words are now “spontaneous” simply because we happen to have been brought up in a particular culture at a particular time. Now these words might well have been used for centuries or even much longer. Yet even that fact (if it is a fact) wouldn’t stop such words from being highly contingent and variable entities.

For example, think here of how the words “troll”, “hi-fi”, “progressive”, “computer”, “transgender”, “race”, “electron”, etc. would have sounded (or seemed) to a 19th century person - let alone to a person from the 203 BC.

Yet despite all that, the words we use today may still seem entirely natural. Indeed they may even be entirely natural — what else can they be?

But so what?

Problems With Eliminative Materialism

There are problems with Churchland’s position. Take this passage:

“Given a deep and practiced familiarity with the developing idioms of cognitive neurobiology, we might learn to discriminate by introspection the coding vectors in our internal axonal pathways, the activation patterns across salient neural populations, and myriad other things besides.”

This is an odd.

Firstly, it seems to hint at the possibility that literally everyone in our community could — or even should — learn the “idioms of cognitive neurobiology”. Alternatively, does Churchland simply believe that these terms would — or could — be passed down from scientists to the whole population? Surely he can’t believe that they could be taught to — or even enforced upon — the populace! (The word “abolished” has indeed been used in the eliminative materialism literature and might even have been used by Paul Churchland himself — see here.)

The basic point here is that languages aren’t imposed or passed down — they grow organically and over time. Of course particular words or even ways of speaking can be taught, suggested or even imposed. (This is happening today — at least to some extent — in the political domain.) But is it likely that all speakers and thinkers would need to know anything — let alone much — about neurobiology? Again, perhaps the terms from neurobiology will — or may — simply filter down in the way that so many other words/terms from academia or science have filtered down over the years. (This is especially the case when it comes to political terms from academia.)

Conclusion

In purely personal terms, I can’t even imagine expressing anything in terms of my brain’s “coding vectors in internal axonal pathways”, “the activation patterns across salient neural populations”, etc. And that’s simply because I know very little about neurobiology. And most other people know very little about neurobiology too. But, again, Paul Churchland was talking about the future. In addition and as just stated, academic or scientific terms being passed (or filtered) down — if over time — to the populace is a commonplace fact. So perhaps that’s what Churchland had in mind.

[I can be found on Twitter here.]

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