Tuesday 21 December 2010

Lipton on Inference to the Best Explanation

I have been having a quick look at (the late) Peter Lipton’s book Inference to the Best Explanation as preparation for revising a philosophy of science module I am due to teach in January. Given that he supervised my PhD rewrite one might have thought that I would have read his book as, at the very least, a courtesy. But it seems that I cannot, or cannot with any care as it seemed quite unfamiliar.

One key respect in which it proved unfamiliar is in a central aim. Lipton aims to use inference to the best explanation (IBE) to shed light on the kind of inference deployed in science. Rather than using inductive inferences to arrive at a theoretical view of the world and then, distinctly and subsequently, using explanation to shed light on particular phenomena, he proposes that the initial inferences can best be understood as being based on explanation. Science works by looking for explanations. The best potential explanation is likely to be true.

That general idea might be backed up / unpacked through any number of different analyses of explanation. Lipton himself – in what seemed to me to be the best aspect of the book – suggests that the best approach to explanation is contrastive. We do not simply explain a fact but rather a fact rather than a foil. Not just ‘why does Smith have paresis?’ but ‘why does Smith rather than Jones have it; or Smith when Jones does not?’. (The answer that Smith had untreated syphilis will be helpful if Jones did not, but not if he too did. The context matters to the answer sought: the relevant bit of the causal history.) Further, he makes a good case for the irreducibility of contrastive explanation to non-contrastive such as a deductive nomological model of explanation. It is not the case, for example, that to explain why P rather than Q is to explain the logical conjunction of P and not Q.

So with contrastive explanation in mind, Lipton argues that scientific inductive inferences can be understood as based on explanations. Elsewhere he gives a short summary of a clinical inference discussed at length in the book:

A good illustration of this is provided by Ignaz Semmelweis’s nineteenth-century investigation into the causes of childbed fever, an often fatal disease contracted by women who gave birth in the hospital where Semmelweis did his research. Semmelweis considered many possible explanations. Perhaps the fever was caused by `epidemic influences’ affecting the districts around the hospital, or perhaps it was caused by some condition in the hospital itself, such as overcrowding, poor diet, or rough treatment. What Semmelweis noticed, however, was that almost all of the women who contracted the fever were in one of the hospital’s two maternity wards, and this led him to ask the obvious contrastive question and then to rule out those hypotheses which, though logically compatible with his evidence, did not mark a difference between the wards. It also lead him to infer an explanation that would explain the contrast between the wards, namely that women were inadvertently being infected by medical students who went directly from performing autopsies to obstetrical examinations, but only examined women in the first ward. This hypothesis was confirmed by a further contrastive procedure, when Semmelweis had the medics disinfect their hands before entering the ward: the infection hypothesis was now seen also to explain not just why women in the first rather than in the second ward contracted childbed fever, but also why women in the first ward contracted the fever before but not after the regime of disinfection was introduced. This general pattern of argument, which seeks explanations that not only would account for a given effect, but also for particular contrasts between cases where the effect occurs and cases where it is absent, is very common in science, for example wherever use is made of controlled experiments. [Lipton 2000]

Still, if explanation is to shed light on our inductive / scientific practices, the notion of best explanation (or best potential explanation) had better not depend too closely on what seems inductively compelling. So best explanation had better not be most likely explanation at the risk of circularity. Instead, Lipton emphasises the potential initial gap between inductive inference and explanation by distinguishing the likeliest and the loveliest explanation. The likeliest explanation is the explanation that is ‘most warranted’. (An example of a likely but unlovely explanation is that opium puts people to sleep through its dormitive powers. Probably true but unhelpful.) The loveliest explanation is the explanation which provides the most understanding, or is the most explanatory. If IBE relies on the latter rather than the former, it can provide a substantial, rather than a merely trivial, analysis of inductive inference. It can come as a surprise that a lovely explanation lies at the core of inductive inference.

But the cost of emphasising the distinction – in order to preserve the substance of the analysis – is that it prompts the following worry, which Lipton calls Voltaire’s Objection. Why assume that loveliness and truth are correlated? Why assume that we live in the loveliest world?

Lipton’s response to this emphasises, inter alia, the fact that to be a potentially lovely explanation requires already meeting a number of constraints on adequacy. (He does not have a knock down reply to the worry. His aim is to suggest that his account is no worse off than any other when it comes to Humean worries about induction in general and he takes Voltaire’s Objection just to amount to that, in the end.) But the problem of this kind of reply, this direction of travel, is that it undermines the contrast which gave the analysis substance. So the question is then whether the two ‘vectors’ can be balanced: to have enough distinction to shed some light on inductive practices whilst maintaining enough connection to avoid Voltaire’s objection. After all if the analysis were to work there would have to be a connection and a gap: the paradox of analysis, again.

Lipton, P. (2000) ‘Inference to the Best Explanation’ in W.H. Newton-Smith (ed) A Companion to the Philosophy of Science, Oxford: Blackwell pp184-193
Lipton, P. (2004) Inference to the Best Explanation, London: Routledge

Tuesday 14 December 2010

Further thoughts on the likeness argument

There’s been quite a bit of discussion of Neil Pickering’s critique of what he calls the ‘Likeness Argument’ amongst students planning essays in the UCLan philosophy of mental health programme which has helped me rethink my attitude towards it. In his original paper, Pickering concludes feistily thus:

The likeness argument dominates the dispute over the reality of mental illness. As a matter of fact, no one has yet produced a version of it which achieves what it aims and claims to be able to achieve, namely to answer the question whether or not conditions such as schizophrenia really are illnesses or not. Disputes continue on all sides about which likenesses and differences are to count, and what they are to count for. I have argued that the likeness argument cannot close these disputes, because two of the assumptions it relies upon to do so do not stand up to scrutiny. In particular, the idea that the features which should decide the issue (as the first assumption states), are describable independently of views about the issue (as the second assumption states), is false. They are not; and so the likeness argument must fail. [Pickering 2004: 253]

Why then, does the likeness argument fail to settle the matter? In his book The Metaphor of Mental Illness [Pickering 2006], Pickering argues that it depends on two assumptions both of which can be questioned. He says:

If the likeness argument is to resolve this dispute two things must, I think, be taken to be the case:
that there are features of human conditions such as schizophrenia, which decide what category, or kind, these conditions are a member of, and
that, with respect to the presence or absence of these features, a condition such as schizophrenia is describable independent of the category it is assigned to. [ibid: 17]

The first is a general condition derived from a view of how concepts apply to things. The suggestion is that concepts apply in virtue of conditions having objective features. This stands in contrast, for example, to a view where all such concept application depends on an imaginative human judgement. The second is a more specific assumption relevant to the debate about mental illness. It is that the ascription of features to conditions – putative illnesses – can be made independently of a top down decision as to the illness-status of those conditions.

Pickering suggests that both assumptions can be questioned. Criticism of the first – which he calls the ‘weak objection’ to the likeness argument – typically depends on pressing the role of human interests and values in the formation of human concepts. Nevertheless, as he goes on to concede, for the moment at least, there need be no incompatibility between acknowledging a role for interests and values in setting up a scheme of concepts and its autonomous application.

The ‘strong objection’ turns on questioning the second assumption. Pickering argues that the ascription of features to conditions – putative illnesses – depends on the overall category – illness or not – into which they are placed. The argument for this is piecemeal. In each of three cases – alcoholism, attention deficit hyperactivity disorder (ADHD), schizophrenia – he offers competing descriptions of their basic features manifesting first an assumption that they are illnesses and second that they are not. The behavioural features of alcoholism, for example, can equally be described in terms of moral weakness or of causally determined pathological behaviour. The same data can be equally well interpreted in the light of opposing top-down theories. Arguing that this is a general feature of such contested cases, Pickering concludes that the features themselves cannot be used to determine to which overall category the condition belongs. (He goes on to note that this claim also undermines the first assumption and thus his earlier concession was temporary.)

Now in the past, I thought along these lines:
This criticism is, however, not as successful as Pickering suggests. His central claim is that detectable and observable features of a condition, a putative illness, cannot be described without begging the question of the pathological status of that condition. This is not, however, a surprising claim. If the correct description of the features is taken to imply a pathological status then, trivially, it cannot be independent of the overall status. But even if it merely provides evidential support, Pickering has really only undermined a foundationalist version of the likeness argument, one in which observational data can be established independently of any broader theoretical perspectives. But most accounts of scientific theories now accept the theory dependence of data and an essential holism in theory testing. Most would reject a foundational approach to data, as Pickering himself later reports [ibid: 167]. Rejecting foundationalism in favour of scientific holism does not show that the likeness argument (or some version of the likeness argument) cannot work as part of a broader investigation of illness...

But now I am not so sure. Commenting on the suggestions made by two of our students, my colleague Gloria reported her own thought that the concession Pickering himself makes to a defence of the likeness argument against his own ‘weak objection’ is too generous.

Sticking with Pickering’s objection to the first assumption made by likeness argument theorists, both responses identify the qualm I have. In the case of the debate about the reality of mental illness, Ann makes the point that “There seems to be no reason why anyone should accept the similarities as being more significant than the differences,” and Rina follows this up with the observation that “the role of the observer/categorizer/diagnostician is not in the background” (and again that “human interpretation is definitely not in the background as Pickering argues).” The two points seem to me to be closely related: if we have no independent reason for accepting one set of similarities over another (e.g. anatomical lesions over reduced fertility), then the spotlight is going to turn on the person asserting a preference for one set of similarities in comparison with the dissimilarities. We want to know why he privileges just that set, and my suspicion is that the answer is likely to be circular: the likeness theorist probably privileges that set because he already thinks that mental disorder is an illness (Kendell) or he already thinks that mental disorder is a myth (Szasz). In other words, it seems to me as though these theorists have already decided how to conceptualise mental disorder, and then they set in search of similarities/dissimilarities that would serve the favoured conception. More generally, it looks like any likeness argument is going to depend on a favoured conception of mental disorder, rather than the other way around (i.e. that the likeness argument supports/justifies the favoured conception of mental disorder). This leads me to think that there is a vicious circularity underpinning the likeness argument, at Pickering’s Stage 1, and that this is more devastating to this strategy of arguing for the reality (or otherwise) of mental illness than Pickering realises.

There is surely something right about this. As a matter of fact, authors using a likeness argument strategy to argue either against or for the reality of mental illness have picked different criteria and produced different results. It is hard not to suspect that the criteria are picked for the results they produce. Given the dialectic, how else could the selection be disciplined so as not to be question-begging? My previous thought that Pickering was merely assuming and thus opposing a foundational version of the strategy seems to miss the point. How does that thought address this question (of how illness criteria could be selected without begging the central question of the debate for which they have been selected)?

I have today only two rather poor thoughts. One is that the debate concerns both the reality or not of mental illness as a whole but also the reality of mental illnesses. Whilst it is hard to see how a likeness argument could settle the former debate, it might help on the latter. The kind of question it might settle in the latter case concerns the pathological status of particular traits when, for example, the opposing view might be that the trait is a defence against illness, not part of an illness itself. In such a case, there might be sufficient gap between the general criteria of illness selected and their particular application to a novel case. (Of course, there’s no logical gap. But one’s reasons for adopting the general criteria need make no reference to / explicitly anticipate this particular case.)

Given the distinction between the general and the particular debate, I am not sure that a likeness theorist need even be embarrassed by no non-question begging answer to the first debate (about the reality of mental illness in general). But if so, the other thought picks up on my earlier mention of a ‘broader investigation of illness’. We might ask what we want a concept of illness for, what work it is supposed to do. From that inquiry would come a view of the general criteria and from that would follow a view of both mental illness and illnesses. That is, I think, how Jerry Wakefield sees his project: the idea that there is a failure of biological function plays a deep and partially hidden role in our use of the notion of illness. That connection forged, it can come as a surprise what particular results it has (via a likeness argument). But that connection was not made simply with a view to generating particular results.

PS: Original thoughts here. Yet further - more recent - thoughts here.

Pickering, N. (2004) The likeness argument Philosophy, Psychiatry and Psychology 10: 243-54
Pickering, N. (2006) The Metaphor of Mental Illness, Oxford: Oxford University Press

Thursday 9 December 2010

So long ISCRI

Well that is just about it for the International School for Communities Rights and Inclusion, ISCRI. Last week I went to its wake: a pleasant enough meal in an empty restaurant in Preston (pictured) enmeshed in the coldest of winter snaps. By contrast with the 60 or so people who gathered for the first ‘away day’, 10 of us gathered at the end.

Gloria and I, and the philosophy of mental health, will move schools to the School of Nursing, to be renamed the School of Health, in January and I am looking forward to developing some of the themes of the philosophy of mental health for a philosophy for nursing. It might be a good place to develop my interest in the tacit underpinnings of clinical judgement.

Deriving a local urban social theory from Nietzsche

Yesterday, I listened to a talk by Grant Yocom of Oakland University called ‘The 'Last Man' in Detroit: Timely Revisions and New Targets for the Arrows of Longing’. It attempted to derive a kind of ‘local urban social theory’ from Nietzsche and apply it to an analysis of social phenomena in Detroit, a city in decline. Among other things, Grant argued that:

[Nietzsche’s] criticisms are aimed at the embodiments of mass-culture and the various forms value that these embodiments instantiate... [L]ooking at Nietzsche in terms of the concretized case study of post-industrial Detroit reveals that the meta-arguments and normative criticisms offered in his work only make sense when viewed in terms of a particular crisis. Specifically, on the fringe of Detroit we find a number of community organizations that instantiate embedded substantive and needs based forms of normative criticism still themselves beyond good and evil and emerging from the crisis-context in which we find them. [S]uch communities and organizations [are] fine examples of embodied Nietzsche-styled criticisms in action.

The community organizations in question have developed organically in response to a lack of proper supermarkets within the city limits by using abandoned lots for impromptu farms and Grant commended them as exemplifying a kind of creative life force in response to the real troubles the citizens faced. They exemplified the local evolution of ‘new values and new manners of living’ and contrasted with government imposed top down values and policies. Further, stressing their value (as he did) contrasted with a kind of middle class crisis-porn which pessimistically assumed that all was over for the city.

It was an interesting and engaging talk. But I couldn’t help thinking that there was something suspect about the project (of deriving a bespoke social theory from Nietzsche to fit Detroit) for this reason. Outside the admirable purity of philosophy as therapy, philosophy seems to me to have two key moves. It can either say ‘this is how things are because this is how they must be’, drawing on paradigmatically philosophical modal arguments. Or it can say, ‘this is how things should be’ in the more or less honourable tradition of offering normative suggestions, justified to a greater or less extent.

But in Grant’s case, it seemed highly unlikely that any philosophical arguments of the first sort could culminate in the inevitability of community urban farms. That would be too far a stretch for philosophical argument. But if it were the latter move, his dislike of imposed general top down values undermined a role for the very philosophical machinery he imported from elsewhere and applied to the case at hand. A non-philosophical description of the mere fact of such urban farms together with an invitation to agree they were admirable seemed all that was unproblematic.

If I followed his reply to my worry (and I fear I did not: my fault) it was to suggest that there was a very general structural account in accord with the first move (roughly: groups tend to respond well to tough ‘physiological’ challenges) and then a more or less local normative move to suggest that urban farms were indeed a good thing in the context. So rather than plumping for one move or the other, he adopted a delicate embrace of both. I am not sure how this would help, really. But perhaps in a Nietzschean further move, he suggested that the rival interpretation of the fate of Detroit (by Jerry Herron) that he had spent some time criticising might be equally descriptively correct. (That would, I assume, also have consequences for the normative stance to be locally adopted.) That was a nuance too far for me, however.

Wednesday 8 December 2010

Priest on the principle of non-contradiction

An interesting short summary of his thinking on this is here. (This post is simply so I can find the link again!)

Friday 19 November 2010

International Journal of Person-Centered Medicine

I learn (from an invitation to join its editorial board) that there is to be a new journal on person centred medicine edited by Professor Andrew Miles with Professor Juan Mezzich as deputy editor. They write:

The Board of the International Network for Person-Centered Medicine recently gave its formal approval for the creation of a new scholarly periodical, the International Journal of Person-Centered Medicine (Int J Pers Cent Med) to be launched jointly with the University of Buckingham Press in the first trimester of 2011.  This is an exciting and timely development which is intended to make a major contribution to the advancement of the theory and practice of person-centered clinical care.

It looks as though the website will be here.

Wednesday 17 November 2010

A treasury of Travis?

I see that Charles Travis has a personal website with ten or so draft papers for download. Perfect for a lengthy train journey, I find.

Friday 12 November 2010

Delusional atmosphere, the everyday uncanny and the limits of secondary sense

Another work in progress. For a comment on Sass’ response to this criticism of him, see this update.

Delusional atmosphere, the everyday uncanny and the limits of secondary sense

Abstract

In In Paradoxes of Delusion Sass aims to use passages from Wittgenstein to characterise the feeling of mute particularity that forms a part of delusional atmosphere. I argue that Wittgenstein’s account provides no helpful positive account. But his remarks on more everyday cases of the uncanny and the unreal might seem to promise a better approach via the expressive use of words in secondary sense. I argue that this also is a false hope but that there is no interesting explanation of this failure.

Introduction

In Paradoxes of Delusion Louis Sass aims to counter Jaspers’ pessimism about the possibility of empathic understanding primary delusions by developing just such an account.

In this book I attempt to do what, according to Jaspers, cannot be done: to comprehend both empathically and conceptually some of the most bizarre and mysterious symptoms of schizophrenia. [Sass 1994: 6]

Whilst the bulk of Paradoxes of Delusion concerns the idea the relation between schizophrenia and solipsism, a later chapter provides a distinct line of interpretation of the specific schizophrenic symptom: delusional ‘atmosphere’ or ‘mood’ described by Jaspers in his General Psychopathology.

“The environment,” says Jaspers “is somehow different – not to a gross degree – perception is unaltered in itself but there is some strange change which envelops everything with a subtle, pervasive and strangely uncertain light.” Whatever is perceived may seem tremendously specific and meaningful, but without the patient being able to explain why; unfamiliar events and objects may appear to be copies or repetitions of themselves… “objects and events signify something but nothing definite”. [Sass 1994: 97]

The key feature of delusional mood or atmosphere is its uncanny particularity and Sass looks to some passages in Wittgenstein’s Brown Book to attempt to shed light on it.

In Schreber’s Memoirs, the feeling of uncanny particularity emerges most clearly in his discussion of the wasp miracle…”I have most stringent and convincing proof that these beings do not fly towards me by accident…. These animals always appear on definite occasions and in definite order around me.” It seems, rather, that Schreber’s experience of definiteness simply could not have been described more completely. [ibid: 99]

This description presents a problem, however. If that is the best that Schreber can do, he does not seem to have given an account of the content of the experience. Just what can he mean by ‘definite occasions and in definite order’? Presumably, another observer would notice nothing special in the flight of the wasps and Schreber does not explain the pattern that he thinks he sees. So, as Sass asks, how can we characterise or comprehend any experience ‘in which everything looks so completely normal yet at the same time so indescribably, so incomprehensibly, special’?

Sass’ idea is to make use of some passages from the Brown Book in which Wittgenstein examines the idea that grasp of meaning is a particular kind of experience. This provides a key tool for Sass’ purpose. Wittgenstein sketches a distinction between a transitive and an intransitive meaning of ‘particular’.

Now the use of the word “particular” is apt to produce a kind of delusion and roughly speaking this delusion is produced by the double usage of this word. On the one hand, we may say, it is used preliminary to a specification, description, comparison; on the other hand, as what one might describe as an emphasis. The first usage I shall call the transitive one, the second the intransitive one. Thus, on the one hand I say “This face gives me a particular impression which I can't describe”. The latter sentence may mean something like: “This face gives me a strong impression”. These examples would perhaps be more striking if we substituted the word “peculiar” for “particular”, for the same comments apply to “peculiar”. If I say “This soap has a peculiar smell: it is the kind we used as children”, the word “peculiar” may be used merely as an introduction to the comparison which follows it, as though I said “I'll tell you what this soap smells like:...”. If, on the other hand, I say “This soap has a peculiar smell!” or “It has a most peculiar smell”, “peculiar” here stands for some such expression as “out of the ordinary”, “uncommon”, “striking”. [Wittgenstein 1958: 158]

So a transitive use of ‘particular’ introduces a comparison which can then be filled out. An intransitive use marks, instead, mere emphasis, equivalent, perhaps, to saying that something is striking. Wittgenstein goes on to suggest that we can become confused as to the nature of the use of the word that we are making of it at any time. This enables Sass to suggest that one can have an experience characterised by one kind of use and confuse it for one characterised by the other such that ‘when one is having the first, intransitive type of experience, that one is noticing the sort of thing that one actually does notice in the first, transitive type’ [Sass 1994: 104]. And from this Sass concludes:

As Wittgenstein analyses it, this uncanny experience of mute particularity is one of the characteristic delusions engendered by a certain unnatural, reflective stance characteristic of philosophizing. [ibid: 104]

The problem with this approach is that it relies on the idea that Wittgenstein does indeed provide an analysis of an experience of mute particularity. But it is far from clear that he does. I say ‘far from clear that he does’ rather than ‘clear that he does not’ for this reason. Wittgenstein’s analysis, in the passages Sass cites, concerns the view that understanding sameness and difference of meaning can be explained or analysed as sameness and difference of an experience of meaning. It is the idea that the word ‘red’, for example, comes to us in a particular way when we recognize a colour as red. It is to criticise this idea that Wittgenstein draws the distinction between transitive and intransitive meaning.

To shed light on this he compares the idea that one experiences a word in a particular way, with the idea that one might describe one’s bodily posture at any given time as ‘particular’.

You are, of course, constantly changing the position of your body throughout the day; arrest yourself in any such attitude (while writing, reading, talking, etc. etc.) and say to yourself in the way in which you say, “‘Red’ comes in a particular way …”, “I am now in a particular attitude.” You will find that you can quite naturally say this. But aren't you always in a particular attitude? [Wittgenstein 1958: 158-9]

Although it is natural, he suggests, to say this when concentrating on one’s posture it is not that there is a type of posture being picked out. Neither, however, is one’s posture even particularly striking.

And of course you didn't mean that you were just then in a particularly striking attitude. [ibid: 159]

Rather, the naturalness of the use of the word is an artefact of the situation.

What was it that happened. You concentrated, as it were stared at, your sensations. And this is exactly what you did when you said that “red” came in a particular way. [ibid: 159]

And this same idea is then used to try to undermine the compulsion to say that understanding a meaning is a matter of having a particular experience. There are experiences when one uses or understands a word just as one’s body is always in some posture or other. But nothing significant follows from this.

What is particular about the way “red” comes is that it comes while you’re philosophizing about it, as what is particular about the position of your body when you concentrated on it was concentration. We appear to ourselves to be on the verge of giving a characterization of the “way” describing the way, whereas we aren’t really opposing it to any other way. We are emphasizing, not comparing, but we express ourselves as though this emphasis was really a comparison of the object with itself; there seems to be a reflexive comparison. [ibid: 159-60]

The reason for looking at the thrust of Wittgenstein’s argument here is this. As is typical of his later work, there is a mix of both therapeutic understanding and destructive criticism. For Sass’ project to work, it would be necessary that part of the therapeutic understanding was an account of what it is, or would be, to have an experience of ‘mute particularity’ even if this were then criticised as part of the destructive aspect of Wittgenstein’s analysis. But it does not seem that that is the case. The closest that he comes to that is the account of the misleading naturalness of using the word ‘particular’ in the context of concentration. But in the elucidatory but deflating example of bodily posture, the natural utterance, whilst intransitive, does not even mean striking. Whilst natural the utterance still, in some sense, misfires. So there is no suggestion that it expresses an experience of mute particularity and thus no account of that supposed experience is given.

This is, perhaps, unsurprising. Wittgenstein puts talk of ‘particular experiences’ in the mouth of an interlocutor who wishes to explain meaning through characteristic experiences and which he – Wittgenstein – wishes, by contrast, to refute. The more the quest for empathic and therapeutic understanding of the opposing view were to succeed in granting it coherence, the less robust would be the critical counterpoint. Instead, Wittgenstein offers the most minimal account of why one might be tempted to deploy the idea of ‘particular experiences’ and then pulls the rug from under it, leaving no substantial account of what such experiences might be.

For this reason, Sass’ suggestion that we look to where we should not look for an account of meaning to help us understand an experience of mute particularity cannot work.

The everyday uncanny / everyday unreality and secondary sense

Whilst the passages which Sass cites do not seem to be a promising approach to shedding light on what it is to experience the world as uncanny or unreal, Wittgenstein does provide clues elsewhere which are helpful in shedding light on this. One passage runs thus:

Let’s imagine a theatre, the curtain goes up & and we see someone alone in his room walking up and down, lighting a cigarette, seating himself etc. so that suddenly we are observing a human being from outside in a way that ordinarily we can never observe ourselves; as if we were watching a chapter from a biography with our own eyes,--surely this would be at once uncanny and wonderful. More wonderful than anything that a playwright could cause to be acted or spoken on the stage. We should be seeing life itself.--But then we do see this every day & it makes not the slightest impression on us! True enough, but we do not see it from that point of view.—Similarly when E. looks at his writings and finds them splendid (even though he would not care to publish any of the pieces individually) he is seeing his life as God’s work of art... [Wittgenstein MS 109 28: 22.8.1930]

In this example, Wittgenstein suggests a context in which one might come to view a scene as uncanny and wonderful even though the scene coincides with ordinary life. To see ordinary life in the same way would require seeing it also as though it were a theatrical performance: to see it as God’s work of art. But what does that phrase mean? What progress has been made in characterising the content of the experience by invoking such a phrase?

Elsewhere he considers a feeling of unreality and explicitly examines how it might be communicated.

The feeling of the unreality of one’s surroundings. This feeling I have had once, and many have it before the onset of mental illness. Everything seems somehow not real; but not as if one saw things unclear or blurred; everything looks quite as usual. And how do I know that another has felt what I have? Because he uses the same words as I find appropriate.

But why do I choose precisely the word “unreality” to express it? Surely not because of its sound. (A word of very like sound but different meaning would not do.) I choose it because of its meaning. [Wittgenstein 1980 §125.]

In characterising the experience, it is important to distinguish it from a case where things seem somehow fake. Everything here looks as it normally would. So fakery is not what is meant by a feeling of ‘unreality’. But given that, why is the word ‘unreal’ the right word? A first response to that question is that the word is selected for its meaning rather than, for example, its sound. But still it is not being used in its first order, ordinary meaning.

But I surely did not learn to use the word to mean: a feeling. No; but I learned to use it with a particular meaning and now I use it spontaneously like this. One might say--though it may mislead--: When I have learnt the word in its ordinary meaning, then I choose that meaning as a simile for my feeling. But of course what is in question here is not a simile, not a comparison of the feeling with something else. The fact is simply that I use a word, the bearer of another technique, as the expression of a feeling. I use it in a new way. And wherein consists this new kind of use? Well, one thing is that I say: I have a ‘feeling of unreality’--after I have, of course, learnt the use of the word “feeling” in the ordinary way. Also: the feeling is a state. [Wittgenstein 1980 §126.]

Given that the word is not used in its simplest and paradigmatic meaning it might be that it is a metaphor or simile. But that does not seem appropriate in this case. There is no possible justification for how the metaphor or simile is supposed to work. Instead, it is more basic. Although the word is not used in its simplest way and although it is not a simile, it is, still, used in a way which is derivative of that primary sense. It is another case of what, elsewhere, Wittgenstein describes as ‘secondary sense’.

Wittgenstein introduces the notion of secondary sense after having described see aspects on part 2 of the Philosophical Investigations. Wittgenstein suggests that there are some cases of seeing-as which can only be characterised with words used in a ‘secondary sense’. The key instance he gives is the attitude most of us have towards words. We feel that a word carries its meaning somehow immediately with it. It can loose this kind of meaning if repeated. Wittgenstein describes this kind of immediate perception of the meaning of a word in isolation as a form of understanding meaning.

Since Wittgenstein’s official recommendation is to think of understanding as grasp of a practice, the use of the words ‘understanding’ and ‘meaning’ in the case at hand is not straight-forward. It is not a metaphor, however, because nothing can be said to explain why we want to use these words for this kind of experience. But whilst this is not a metaphorical use it is nevertheless a secondary use: one which we find natural given the primary use, but which is discontinuous with, and could not be used to teach, the primary use [Wittgenstein 1953: 216]. Another example Wittgenstein gives is the use of ‘fat’ in the claim that Wednesday is fat. Clearly Wednesday cannot in any ordinary sense be compared with other fat or thin things. And it would be optimistic to attempt to teach the meaning of ‘fat’ by giving Wednesday as an example. Nevertheless, many language users give spontaneous expression to the thought that Wednesday is a fat day.

Whilst experiencing the meaning of a word or ascribing a width to days of the week may seem to be of limited interest, the Wittgensteinian philosopher Oswald Hanfling argues that the secondary use of words is widespread [Hanfling1991]. In aesthetics, he argues, words such as ‘sad’ applied to music are used in secondary sense. (The music need not make a hearer sad, does not sound like a sad person etc.)

Words in secondary sense are also used in the expression of some moods and feelings. In characterising how such a feeling feels, in describing its ‘content’, one makes use of a phrase that does not straightforwardly mean (in this context) what it seems to say, although what it is used to say in the context depends on its primary meaning. To see ‘life as God’s work of art’ looks to be such a use. To say that something is or feels unreal or uncanny is the same. The scene is not really unreal. Nor could it feel as if it were unreal. (What would that be? What would it be if true?)

Secondary sense and delusional atmosphere

But if the ‘everyday’ sense of the uncanny is a matter for secondary sense, could the same approach work for the psychopathological case of delusional atmosphere? Could it also be a matter of ‘seeing as’ albeit expressed only in secondary sense? To consider this, it is helpful to contrast Schreber’s ‘stringent and convincing proof’ that he finds in the definiteness of the flight of wasps with both seeing the duck-rabbit as a duck and hearing meaning in a word. There is a key disanalogy in each case.

First, some further account can be given of the experience of seeing the duck-rabbit as a duck. One can say that one now seeing these protuberances as the beak, the direction of gaze is now to the left etc.. In Schreber’s case, as Sass emphasises, no further clarification by Schreber is available of how he experiences the wasp order. (This is why Sass talks of an intransitive sense of particularity.)

Second, unlike the experience of hearing meaning in a word, we lack a shared spontaneous use of ‘proof’ in anything like the wasp case. There is no agreement that it is natural to use that word in the face of apparently random wasp flight. In the face of this absence, one might still hypothesise that Schreber is using the word ‘proof’ in secondary sense. But that would be at most a kind of external structural description of his utterance justified by external marks or indication of such a use and, aside from spontaneous agreed use, it is not clear that there are any such marks.

It might be tempting (it is for me) to draw a firmer conclusion from such a case and to say that there is a limitation on the kind of secondary sense that words can carry. Somehow ‘proof’ in the context of wasp flight, just cannot carry the meaning Schreber wants to give it. But that would be to mythologize secondary sense in the same way that construing the limits of sense as limitations mythologizes primary sense.

The more modest conclusion is that just as in the case of primary sense there are combinations of symbols to which we have not given a meaning (there is no custom, practice or institution for combining them that way), so in the case of secondary sense, we have not spontaneously found a role for a characteristic expressive use. If that is the correct, modest, conclusion, how characteristic does the role have to be?

When dealing with a ‘feeling of unreality’, we are inclined to say: “All I know is that under certain circumstances human beings often say that they felt everything around them was ‘unreal’. Naturally we also know what use of this word the people had learnt, and besides that something about their other utterances. More we do not know.”--Why don’t we talk in the same way when what is in question is utterances expressive of pleasure, of conviction, of the voluntariness and involuntariness of movements? [Wittgenstein 1980 §789]

We can say something in reply to this. The expressive uses of language for pleasure, conviction and voluntariness can all be disciplined by both third person criteria and further descriptions of use. By contrast, the further descriptions that apply to feeling of unreality are few and closely dependent on its first person expression (not vice versa).

But just as ‘butterflies in the stomach’ can take on stable third person conditions of use so there does not seem to be any principled barrier to less familiar use gaining more connections to a richer description of the context for its ‘proper’ use. Unusual secondary sense expression is just the limit case of this.

If so, the limits of secondary sense relevant to charting psychopathology may be porous and there is no interesting explanation of why we do not understand Schreber, if we do not. We just do not.

Bibliography

Read, R. (2001) ‘On approaching schizophrenia through Wittgenstein’ Philosophical Psychology 14: 449-475
Sass, L.A. (1994) The Paradoxes of Delusion, New York: Cornell
Wittgenstein, L. (1958) The Blue and Brown books, Oxford: Blackwell
Wittgenstein, L. (1980) Remarks on the Philosophy of Psychology, Oxford: Blackwell
Wittgenstein, L. MS

Wednesday 10 November 2010

On the very idea of a recovery model for mental health

My co-authored (with Peter Lucas) paper 'On the very idea of a recovery model for mental health' is now available in online preview with the Journal of Medical Ethics.

By chance, I'll be giving a version of the paper as a presentation to the Manchester University mental health forum at 4pm Thursday November 25th.

See also this later entry on a chapter on recovery for an OUP book.

Monday 8 November 2010

Clinical judgement, tacit knowledge and recognition in psychiatric diagnosis

Very much a work in progress, obviously, but this is my working up a chapter for Bill Fulford's OUP Handbook of the Philosophy of Psychiatry.

Clinical judgement, tacit knowledge and recognition in psychiatric diagnosis

Abstract
This chapter contrasts the recent emphasis on operationalism as the route to reliability in psychiatry with arguments for an ineliminable role for tacit knowledge. Although Michael Polanyi is widely credited with arguing for the presence of a tacit dimension, I argue that his account needs to augmented with Wittgenstein’s version of a regress argument for the centrality of know-how over knowledge-that. That argument, however, suggests two possible roles for tacit knowledge. I argue that the more radical version presupposes the very platonic picture that the argument is supposed to oppose. The more modest version presents a tacit element as a kind of limit condition on knowledge.

Introduction

In this chapter, I will examine the role of clinical judgement in the recognition of psychiatric symptoms via the idea that this involves an ineliminable tacit dimension. I will do this by examining, at breakneck speed, three authors who offer support for the idea.

One reason for doubting, or playing down, a role for tacit knowledge in psychiatric diagnosis is the influence of operationalism in a quest for reliability for the last 50 years or so. There were two main factors which explain this.

Firstly, on its foundation in 1945, the World Health Organisation set about establishing an International Classification of Diseases (ICD). Whilst the chapters of the classification dealing with physical illnesses were well received, the psychiatric section was not widely adopted and so the British psychiatrist Erwin Stengel was asked to propose a basis for a more acceptable classification. Stengel chaired a session at an American Psychological Association conference of 1959 at which the philosopher Carl Hempel spoke. As a result of Hempel’s paper (and an intervention by the UK psychiatrist Sir Aubrey Lewis) Stengel proposed attempts at a classification based on theories of the causes of mental disorder should be given up (because such theories were premature) and to rely instead on what could be directly observed, that is, symptoms.

In fact, Hempel’s paper provided only partial support for the moral that was actually drawn for psychiatry. He argued that:
Broadly speaking, the vocabulary of science has two basic functions: first, to permit an adequate description of the things and events that are the objects of scientific investigation; second, to permit the establishment of general laws or theories by means of which particular events may be explained and predicted and thus scientifically understood; for to understand a phenomenon scientifically is to show that it occurs in accordance with general laws or theoretical principles. [Hempel 1994: 317]

These two requirements – that terms employed in classifications should have clear, public criteria of application and should lend themselves to the formulation of general laws – correspond to the aims of reliability and validity respectively. But it was the former that was adopted by psychiatry as the key aim at the time. With respect to it, Hempel claims that
Science aims at knowledge that is objective in the sense of being intersubjectively certifiable, independently of individual opinion or preference, on the basis of data obtainable by suitable experiments or observations. This requires that the terms used in formulating scientific statements have clearly specified meanings and be understood in the same sense by all those who use them. [ibid: 318]

He commends the use of operational definitions (following Bridgman’s book The Logic of Modern Physics [Bridgman 1927]), although he emphasises that in psychiatry the kind of measurement operations in terms of which concepts would be defined would have to be construed loosely and this view has been influential up to the present WHO psychiatric taxonomy in ICD-10.

The second reason for the emphasis on reliability and hence operationalism was a parallel influence from within American psychiatry that shaped the writing of DSM-III. Whilst DSM-I and DSM-II had drawn heavily on psychoanalytic theoretical terms, the committee charged with drawing up DSM-III drew on the work of a group of psychiatrists from Washington University of St Louis. Responding in part to research that had revealed significant differences in diagnostic practices between different psychiatrists, the ‘St Louis group’, led by John Feighner, published operationalised criteria for psychiatric diagnosis. The DSM-III task force replaced reference to Freudian aetiological theory with more observational criteria. The task force leader, Robert Spitzer, later reported: ‘With its intellectual roots in St. Louis instead of Vienna, and with its intellectual inspiration drawn from Kraepelin, not Freud, the task force was viewed from the outset as unsympathetic to the interests of those whose theory and practice derived from the psychoanalytic tradition.’ [Bayer and Spitzer 1985: 188 quoted in Shorter 1997: 301-2].

This stress on operationalism has had an effect on the way that criteriological diagnosis is codified in DSM and ICD manuals. Syndromes are described and characterised in terms of disjunctions and conjunctions of symptoms. The symptoms are described in ways influenced by operationalism and with as little aetiological theory as possible. (That they are neither strictly operationally defined nor strictly aetiologically theory free is not relevant here.) Thus one can think of such a manual as providing guidance for, or a justification of, a diagnosis offered by saying that a subject is suffering from a specific syndrome. Thus, presented with an individual, the diagnosis of a specific syndrome is justified because he or she has enough of the relevant symptoms which can be, as closely as possible, ‘read off’ the subject. Such an approach to psychiatric diagnosis plays down the role of individual judgement or tacit knowledge amongst clinicians.

Polanyi on tacit knowledge
Whilst the influence of operationalism deployed in the service of reliability aims to remove or reduce the presence of judgement and thus an uncodified tacit element in psychiatric diagnosis, there is a tradition in the history and philosophy of science (dating from about the same time) which stresses an ineliminable role for tacit knowledge in science. In this section, I will examine arguments offered by the chemist turned philosopher of science Michael Polanyi.

But first, what does Polanyi mean by ‘tacit’ knowledge? A clear statement runs thus:
I shall reconsider human knowledge by starting from the fact that we can know more than we can tell. This fact seems obvious enough; but it is not easy to say exactly what it means. Take an example. We know a person’s face, and can recognize it among a thousand, indeed among a million. Yet we usually cannot tell how we recognize a face we know. So most of this knowledge cannot be put into words. [Polanyi 1967: 4]
The suggestion is that tacit knowledge is tacit because it is ‘more than we can tell’. We cannot tell how we know things that we know tacitly. But what argument does he give for this? What are the limits on what can be said still leaving something that can be known?

In Personal Knowledge, Polanyi’s strategy is to examine how what can be said or, more broadly, articulated both leaves room for and depends on something outside what can be articulated. There are two key arguments of relevance to this chapter. One depends on limits on the kind of representation available to summarise explicit knowledge in science, thus indicating a space for tacit knowledge. The other depends on an analysis of what is involved in recognition (an argument which promises to impact on diagnostic judgement), which also connects to Polanyi’s views of how linguistic representation in general is possible. I will suggest that this latter argument is the fundamental argument but start with the former.

To examine the limits of scientific representation, Polanyi considers the understanding that a skilled surgeon has of the spatial configuration and orientation of organs in the body. He argues that this cannot be captured in a representation.
The major difficulty in the understanding, and hence in the teaching of anatomy, arises in respect to the intricate three-dimensional network of organs closely packed inside the body, of which no diagram can give an adequate representation. Even dissection, which lays bare a region and its organs by removing the parts overlaying it, does not demonstrate more than one aspect of that region. It is left to the imagination to reconstruct from such experience the three-dimensional picture of the exposed area as it existed in the unopened body, and to explore mentally its connections with adjoining unexposed areas around it and below it.
The kind of topographic knowledge which an experienced surgeon possess of the regions on which he operates is therefore ineffable knowledge. [Polanyi 1962: 89]

The claim here is that three-dimensional spatial knowledge is ineffable, or tacit, because it cannot be captured in a representation. Polanyi goes on to argue that even if all human bodies were identical and even if there were a map comprising cross sections based on ‘a thousand thin slices’ of the body, that in itself would not articulate the knowledge of a trained surgeon. Someone knowing merely the former ‘would know a set of data which fully determine the spatial arrangement of the organs in the body; yet he would not know that spatial arrangement itself’ [89]. An additional act of interpretation or imagination is needed. But because that act cannot itself be encoded in a representation, according to Polanyi, it remains tacit.

This argument is a little surprising. Polanyi concedes that the set of cross sectional representations, presumably alongside some further information about their inter-relations such as their order and distance apart, ‘fully determine[s] the spatial arrangement of the organs’ and yet denies that this amounts to an articulation of the three-dimensional understanding.

Without the further information about the relations between the set of maps, the maps alone would not be an articulation of the skilled surgeon’s knowledge. But then neither would they fully determine the arrangement of bodily organs. With that addition, however, why would this not count as an articulation of their knowledge and thus imply that it could be explicit knowledge?

A further possible clue to Polanyi’s thinking runs thus:
The difficulty lies here entirely in the subsequent integration of the particulars and the inadequacy of articulation consists altogether in the fact that the latter process is left without formal guidance. The degree of intelligence required from the student to perform the act of insight which ultimately conveys to him the knowledge of the topography, offers here a measure of the limitations of the articulation representing this topography. [ibid: 90]

But there remains something strange about this line of thought. If the integration of the partial representations, such as the set of cross sections, were left without formal guidance then it would be clear why the partial representations could not articulate the surgeon’s knowledge. But neither would they determine the arrangement of organs as Polanyi has previously asserted.

The difficulty with interpreting this argument is that of balancing the claim that spatial configuration is both determined by what can be represented but remains ineffable and thus tacit rather than explicit.
I think that the clue to its interpretation is to realise that whether a symbol logically determines anything always, according to Polanyi, depends on a tacit element. This is supported by a different argument.
I may ride a bicycle and say nothing, or pick out my macintosh among twenty others and say nothing. Though I cannot say clearly how I ride a bicycle nor how I recognise my macintosh (for I don’t know it clearly), yet this will not prevent me from saying that I know how to ride a bicycle and how to recognise my macintosh. For I know that I know how to do such things, though I know the particulars of what I know only in an instrumental manner and am focally quite ignorant of them. [ibid: 88]

Polanyi suggests that the skill involved in the example of recognising a macintosh is akin to the practical skill of cycle riding. In both cases, the ‘knowledge-how’ depends on something which is not explicit: the details of the act of bike riding or raincoat recognition. Whilst one can recognise one’s own macintosh, in the example, one is ignorant of how. Thus how one does this is tacit.

If this argument were successful it would be of general significance because it would carry over to the recognitional skill which underpins classification such as diagnosis in psychiatry but also lingusitic labelling generally. Indeed, Polanyi makes this connection explicilty.
[I]n all applications of a formalism to experience there is an indeterminacy involved, which must be resolved by the observer on the ground of unspecified criteria. Now we may say further that the process of applying language to things is also necessarily unformalized: that it is inarticulate. Denotation, then, is an art, and whatever we say about things assumes our endorsement of our own skill in practising this art. [ibid: 81]

This connection between denotation and tacit recognitional skills appears to be the fundamental argument for the importance of tacit knowledge for explicit scientific accounts. Polanyi summarises the connection thus:
If, as it would seem, the meaning of all our utterances is determined to an important extent by a skilful act of our own – the act of knowing – then the acceptance of any of our own utterances as true involves our approval of our own skill. To affirm anything implies, then, to this extent an appraisal of our own art of knowing, and the establishment of truth becomes decisively dependent on a set of personal criteria of our own which cannot be formally defined.... [E]very where it is the inarticulate which has the last word, unspoken and yet decisive... [ibid: 70-71]

Nevertheless, this argument faces two objections.
First, it involves the claim that recognition of particulars – such as a particular macintosh – depends on features of them of which one is ignorant. The example concerns the recognition of a particular macintosh among a pile of them. Not the recognition that the object is a macintosh, but that that particular macintosh is mine. Now it may be true that the recognition of a particular macintosh (as mine, eg.) turns on features of which I am ignorant (although see my second criticism below) but that is not quite the claim Polanyi needs if he wishes to make a point about the ‘art of denotation’ in general.

For that, he needs the claim that recognition of something as an instance of the type ‘macintosh’ is based on the recognition of subsidiary properties of which one is ignorant. But it is not clear that any such claim is true. Unless at least some properties were directly recognisable, it would lead to a vicious regress. But if some properties were directly recognisable the argument would not establish the generality of a tacit dimension. Some recognitional judgements would depend on tacit elements but not all.

Second, it is not clear that it is right to say that to even in cases where one recognises an F in virtue of its subsidiary properties G, H, I of which one cannot give an independent account, or recognises one particular F (as mine, eg.) on such a bais, that one is ignorant of those properties. It may be, instead, that the awareness one has of G, H, I is manifested in the recognition of something as an F or a particular F. One might say, I recognise that it is my macintosh (or a macintosh rather than any other kind of raincoat) because of how it looks here with the interplay of sleeve, shoulder and colour even if one could not recognise a separated sleeve, shoulder or paint colour sample as of the same type. So it is not clear that Polanyi’s is a convincing account of the tacit properties of recognition even when it does depend on component aspects.

The tacit element in recognition

I argued in the previous section that Polanyi’s argument for the role of a tacit element in science turns on an argument that it is fundamental in recognition, including the recognition which underpins the ‘art of denotation’. He suggests that tacit knowledge is that which falls outside linguistic articulation or representation. But such representation presupposes recognitional know-how rather than the other way round. So the know-how which constitutes recognition is not itself articulated but rather tacit.

I argued, however, that Polanyi’s argument for the role of tacit knowledge in recognition is not successful as a general account because he has to assume that to recognise a feature (F, say) one must a) always recognise it in virtue of something else (subsidiary features G, H and I, eg.) of which b) one is ignorant. But neither point – a) and b) – is compelling. There is, however, another argument which was framed at about the same time as Polanyi’s which turns on an idea that recognition of something might resist being put into words (which Polanyi takes to indicate tacit-status). This is Ryle’s argument that knowledge-how is a concept logically prior to the concept of knowledge-that.

Ryle’s argument takes the form of a regress.
If a deed, to be intelligent, has to be guided by the consideration of a regulative proposition, the gap between that consideration and the practical application of the regulation has to be bridged by some go-between process which cannot by the pre-supposed definition itself be an exercise of intelligence and cannot, by definition, be the resultant deed. This go-between application- process has somehow to marry observance of a contemplated maxim with the enforcement of behaviour. So it has to unite in itself the allegedly incompatible properties of being kith to theory and kin to practice, else it could not be the applying of the one in the other. For, unlike theory, it must be able to influence action, and, unlike impulses, it must be amenable to regulative propositions. Consistency requires, therefore, that this schizophrenic broker must again be subdivided into one bit which contemplates but does not execute, one which executes but does not contemplate and a third which reconciles these irreconcilables. And so on for ever. [Ryle 1945: 2]

There has been a recent flurry of literature on the precise nature of this argument and thus whether it is a successful refutation of intellectualism [eg Stanley and Williamson 2001; Noë 2005]. But it seems to involve something like the following regress:
Suppose all know-how can be articulated (put into words) as a piece of knowledge-that: grasping some proposition that p. Grasping the proposition that p is itself something one can do successfully or unsuccessfully, so it is also a piece of know-how. So, on the theory in question, it will involve grasping another proposition, call this q. But grasping the proposition that q is itself something one can do successfully or unsuccessfully, so it is also a piece of know-how. So, on the theory in question, it will involve grasping another proposition, call this r.... etc

This argument seems to suggest that, if the first step of the argument is designed to ‘articulate’ or represent a piece of otherwise merely tacit knowledge at the heart of recognition, it will lead to a regress. But that may prompt this thought, contra Polanyi. Suppose that one recognises a macintosh as a macintosh and thus denotes it ‘macintosh’. Why is that not what articulating this piece of recognitional knowledge amounts to, thus discharging any tacit element? Why is that not putting all the relevant knowledge in play into words?
One gets a clearer sense of the attraction of Polanyi’s position by seeing both what has to be ruled out in successful recognition and on what limited basis it seems to be known by looking to Wittgenstein’s version of a regress argument (also from about the same time). Wittgenstein considers what is grasped by someone who has grasped a mathematical rule or series which he approaches via the idea of teaching the +2 series.

Now we get the pupil to continue a series (say + 2) beyond 1000–and he writes 1000, 1004, 1008, 1012.
We say to him: “Look what you’ve done!”–He doesn’t understand. We say: “You were meant to add two: look how you began the series!”–He answers: “Yes, isn’t it right? I thought that was how I was meant to do it.”–Or suppose he pointed to the series and said: “But I went on in the same way.”–It would now be no use to say: “But can’t you see....?”–and repeat the old examples and explanations.–In such a case we might say, perhaps: It comes natural to this person to understand our order with our explanations as we should understand the order: “Add 2 up to 1000, 4 up to 2000, 6 up to 3000 and so on.” [Wittgenstein 1953: §185]

In passages such as these, Wittgenstein seems to stress the infinite possibilities of divergence and thus the infinite possibilities of a breakdown of communication. Given his concurrent criticisms, in surrounding passages of the Philosophical Investigations, of physiological mechanisms, mental talismans and platonic structures to explain our grasp of going on in the correct way it can seem the most fragile contingency that communication is possible [cf Lear 1982]. Since teaching rules (whether mathematical or empirical) is possible only either by paraphrase, which merely postpones the problem of explaining the paraphrase, or by finite examples, which seem to underdetermine the rule, grasp of a rule which governs a potentially unlimited number of cases seems to need some further helping hand.

This line of thought provides a role for tacit knowledge. Since everything that can be said still allows for the kind of misunderstanding exemplified by Wittgenstein’s hypothetical deviant pupil, the grasp of a rule that a normal pupil acquires must be based on something unsaid and implicit. It must depend on a tacit element. This seems also to fit Wittgenstein’s own conclusion:
What this shews is that there is a way of grasping a rule which is not an interpretation, but which is exhibited in what we call “obeying the rule” and “going against it” in actual cases. [Wittgenstein 1953: §202]

But whilst I think that there is something right about that line of thought, there is something misleading about it. The risk is that it accepts part of what Wittgenstein criticises: a platonic picture of rules as rails ‘invisibly laid to infinity’ fundamentally distinct from our capacity to articulate them.

That picture is easily prompted by cases of deviant pupils. What they seem to show is both that any finite set of examples underdetermines a correct understanding of the rule but also that such correct understanding must involve grasp of an extra-human or supernatural pattern. Since no actual human enumeration of the pattern seems enough to determine it, it must be extra-human. Hence the metaphor of rails laid to infinity.
With that picture of the way rules determine correct moves in place, there is a substantial role for tacit knowledge to bridge the gap between what can be made explicit in the sublunary realm and the ideal platonic standard. Wittgenstein undermines that gap, however, in passages in which he suggests that there is a close connection between what a teacher can express and what a student can grasp in the examples which manifest the teacher’s meaning.

“But do you really explain to the other person what you yourself understand? Don't you get him to guess the essential thing? You give him examples,--but he has to guess their drift, to guess your intention.” – Every explanation which I can give myself I give to him too. – “He guesses what I intend” would mean: various interpretations of my explanation come to his mind, and he lights on one of them. So in this case he could ask; and I could and should answer him. [ibid: §210]
“But this initial segment of a series obviously admitted of various interpretations (e.g. by means of algebraic expressions) and so you must first have chosen one such interpretation.”–Not at all. A doubt was possible in certain circumstances. But that is not to say that I did doubt, or even could doubt…[ibid: §213]

Whilst Wittgenstein rejects substantive explanations of our grasp of rules by pointing out they could not determine what they are supposed to, he does not promote a kind of sceptical gap between what can be manifested and what must be understood for communication, a gap that has thus to be filled by a tacit element. So the role for tacit knowledge in the recognition is not quite that.

The real role for a tacit element in recognition of sameness and difference is nuanced. It is not that it plugs a gap between what can be expressed and a platonic standard, a gap that would downplay the expressive capacities of explanations by example. Recognising that our understanding can be expressed in examples, for those with eyes to see at least, undermines the gap between the sublunary and the platonic. Nevertheless, the failure of the kind of platonic explanation of what it is to follow a rule suggests an important role for human judgement. It is because we are the kind of subjects that we are, with our shared routes of interest, perceptions of salience, feelings of naturalness etc., that we are able to use finite explanations, as we do, to communicate unending rules [Lear 1982: 386]. Against that background, the rules one grasps can be manifested in explanations. Wittgenstein’s deviant pupil thus illustrates what it would be to lack the right background and thus fail to understand explanations by example as we do.

Now it might be tempting to obviate the need for such a background by trying to articulate or encode how understanding depends on one’s interests, saliences and perceptions of naturalness. But any attempt to articulate that would also have to presuppose the background that underpins understanding of any such explanation.

This suggests a nuanced view of the role for tacit knowledge in rule-governed recognition. There is no gap between explanation and rule to be plugged by tacit knowledge, as would be suggested by partial adoption of a platonic picture. Explanations can manifest one’s understanding of a rule and thus it is not tacit in Polanyi’s sense. But such explanations presuppose a background which cannot be fully articulated. Whatever can be expressed, something remains implicit.

Tacit knowledge, clinical judgement recognition and psychiatric symptoms

I began by outlining the importance of reliability and thus the stress on operationalism for psychiatric taxonomy and diagnosis. For the last half century, syndromes have been defined in terms of conjunctions and disjunctions of symptoms which have themselves been described in terms as free of aetiology as practical. (For some conditions, such as PTSD, that would be impossible.) Thus the diagnosis of a specific syndrome is justified in the presence of a particular subject if he or she has enough of the relevant symptoms.

This approach is aimed at closing the gap between syndrome and subject and thus increasing inter-rater reliability among clinicians. Because of the way both ICD and DSM base syndromes on a combination of conjunction and disjunction of symptoms, it is possible that a syndrome so defined may apply to two individuals with little, or even no, overlap of symptoms. But these differences are codified rather than left to an overall uncodified clinical judgement. Further, the heritage of operationalism suggests that individual symptoms can be tied to subjects through a kind of measuring operation.

There remains, however, a gap between the description or articulation of a symptom and an individual. The concepts of specific symptoms are, despite their specificity, general concepts that can be instantiated in an unlimited number of actual or potential cases. So how can one judge that a general concept applies to a specific individual case or individual person? How can one recognise that they exemplify a type? One can attempt to bridge this gap. Textbooks of psychiatry can describe, rather than merely list, symptoms. But whatever descriptive account they give of symptoms, there will always be a gap between their general descriptions and concepts (which potentially apply to any number of individuals) and any particular individual. Bridging this gap calls for expertise which can be called tacit in the nuanced way set out above. It calls for a skilled recognitional clinical judgement.

Bibliography

Bayer, R. and Spitzer, R.L. (1985) ‘Neurosis, psychodynamics and DSM-III’ Archives of General Psychiatry 42: 187-96
Bridgman, P.W. (1927) The Logic of Modern Physics, New York: Macmillan
Hempel, C.G. (1994) ‘Fundamentals of taxonomy’ in Sadler, J.S. Wiggins, O.P. and Schwartz, M.A. (eds) Philosophical Perspectives on Psychiatric Diagnostic Classification, Baltimore: Johns Hopkins: 315-331
Lear, J. (1982) ‘Leaving the world alone’ Journal of Philosophy 79: 382-403
Noë, A. (2005) ‘Against intellectualism’ Analysis 65: 278-90
Polanyi, M. (1962) Personal Knowledge, Chicago: University of Chicago Press
Polanyi, M. (1967) The Tacit Dimension, Chicago: University of Chicago Press
Ryle, G. (1949) The Concept of Mind, London: Hutchinson.
Ryle, G (1945) ‘Knowing How and Knowing That’ Proceedings of the Aristotelian Society, 46: 1-16
Shorter, E. (1997) A History of Psychiatry, New York: John Wiley and Sons
Stanley, J. and Williamson, T. (2001) ‘Knowing how’ The Journal of Philosophy 97: 411-444.
Wittgenstein, L. (1953) Philosophical Investigations, Oxford: Blackwell.

Tuesday 2 November 2010

Tacit knowledge in Polanyi's Personal Knowledge

(This entry will be superceded by my chapter on tacit knowledge and diagnosis.)

The idea that science has an essential and ineliminable tacit element was first popularised in the twentieth century by the chemist turned philosopher Michael Polanyi. He begins his book length treatment of tacit knowledge in The Tacit Dimension by saying:

I shall reconsider human knowledge by starting from the fact that we can know more than we can tell. This fact seems obvious enough; but it is not easy to say exactly what it means. Take an example. We know a person’s face, and can recognize it among a thousand, indeed among a million. Yet we usually cannot tell how we recognize a face we know. So most of this knowledge cannot be put into words. [Polanyi 2009: 4]

The suggestion is that tacit knowledge is tacit because it is ‘more than we can tell’. We cannot tell how we know things that we know tacitly. But what argument does he give for this? What are the limits on what can be said still leaving something that can be known?

In Personal Knowledge, Polanyi’s strategy is to examine how what can be said or, more broadly, articulated both leaves room for and depends on something outside what can be articulated. There are two key arguments. One depends on the kind of representation available to summarise explicit knowledge in science. The other depends more broadly on recognition from which follow more general claims about representation. I will suggest that the latter is the fundamental argument but start with the former.

Taking the example of knowledge of the spatial configuration of organs in the body, Polanyi argues this cannot be captured in a representation.

The major difficulty in the understanding, and hence in the teaching of anatomy, arises in respect to the intricate three-dimensional network of organs closely packed inside the body, of which no diagram can give an adequate representation. Even dissection, which lays bare a region and its organs by removing the parts overlaying it, does not demonstrate more than one aspect of that region. It is left to the imagination to reconstruct from such experience the three-dimensional picture of the exposed area as it existed in the unopened body, and to explore mentally its connections with adjoining unexposed areas around it and below it.
The kind of topographic knowledge which an experienced surgeon possess of the regions on which he operates is therefore ineffable knowledge. [Polanyi 1974: 89]

Three-dimensional spatial knowledge is ineffable or tacit because it cannot be captured in a representation. Polanyi argues that even if all human bodies were identical and even if there were a map comprising cross sections based on ‘a thousand thin slices’ of the body, that in itself would not articulate the knowledge of a trained surgeon. Someone knowing merely the former ‘would know a set of data which fully determine the spatial arrangement of the organs in the body; yet he would not know that spatial arrangement itself’ [89]. An additional act of interpretation is needed. But because that act cannot itself be encoded in a representation, according to Polanyi, it remains tacit.

The argument is a little surprising. Polanyi concedes that that the set of cross sectional representations, presumably alongside some further information about their inter-relations, such as their order and distance apart, ‘fully determine[s] the spatial arrangement of the organs’ and yet denies that this amounts to an articulation of the three-dimensional understanding. Without the further information this certainly would not be an articulation of the skilled surgeon’s knowledge. But then neither would it fully determine the arrangement. With that addition, however, why would this not count as explicit knowledge?

A further clue runs thus:
The difficulty lies here entirely in the subsequent integration of the particulars and the inadequacy of articulation consists altogether in the fact that the latter process is left without formal guidance. The degree of intelligence required from the student to perform the act of insight which ultimately conveys to him the knowledge of the topography, offers here a measure of the limitations of the articulation representing this topography. [ibid: 90]

Again there is something confusing here. If the integration of partial representations such as the set of cross sections really is left without formal guidance then, again, it is clear why they cannot articulate the full knowledge. But neither would they determine the arrangement.
The difficulty with interpreting this argument is that of balancing the claim that spatial configuration is both determined but also ineffable.

I think that the clue to its interpretation is to realise that whether a symbol logically determines anything always, according to Polanyi, depends on a tacit element. This is supported by the first argument.

I may ride a bicycle and say nothing, or pick out my macintosh among twenty others and say nothing. Though I cannot say clearly how I ride a bicycle nor how I recognise my macintosh (for I don’t know it clearly), yet this will not prevent me from saying that I know how to ride a bicycle and how to recognise my macintosh. For I know that I know how to do such things, though I know the particulars of what I know only in an instrumental manner and am focally quite ignorant of them. [ibid: 88]

Polanyi suggests that the recognitional skill involved in the second example is akin to the practical skill of the first. In both cases, the knowledge-how depends on something which is not explicit: the details of the act of bike riding or raincoat recognition. But if that is the case then recognising instances of the same linguistic or conceptual type looks also to be a case of a recognitional skill in which the particular clues to the recognition are unknown.

[I]n all applications of a formalism to experience there is an indeterminacy involved, which must be resolved by the observer on the ground of unspecified criteria. Now we may say further that the process of applying language to things is also necessarily unformalized: that it is inarticulate. Denotation, then, is an art, and whatever we say about things assumes our endorsement of our own skill in practising this art. [ibid: 81]

This connection between denotation and tacit recognitional skills appears to be the fundamental argument for the importance of tacit knowledge for explicit scientific accounts. Polanyi summarises the connection thus:
If, as it would seem, the meaning of all our utterances is determined to an important extent by a skilful act of our own – the act of knowing – then the acceptance of any of our own utterances as true involves our approval of our own skill. To affirm anything implies, then, to this extent an appraisal of our own art of knowing, and the establishment of truth becomes decisively dependent on a set of personal criteria of our own which cannot be formally defined.... [E]very where it is the inarticulate which has the last word, unspoken and yet decisive... [ibid: 70-71]

But if this is the key argument, everything depends on the strength of the claim that recognition requires a tacit element.

Monday 1 November 2010

One song to the tune of another

By contrast with my previous Brewery Arts visit, the Bad Shepherds are not really in the business of singing cover versions of the songs they play. They are a three piece modern folk band (amplified pipes, fiddles and mandolins) and the songs they sing share the lyrics, and some musical themes, of key 1980s pop / punk / post-punk songs. But it is as though the songs have been completely taken apart and reconstructed on different rhythms, harmonies and, perhaps even, time signatures. And thus each begins by prompting a period of tense and curious anticipation for the listener. Just what song will emerge?

In the end, I found the re-emergence in every song of the same kind of celtic folk arpeggios beginning to grate. I wanted to hear something of the directness of the originals. (Had things been reversed, would the emergence of post-punk features been similarly grating? Possibly.) But the focus on the lyrics of the songs produced some gems. 'Down In The Tube Station At Midnight' was no longer just a good Jam song but a good song. And there was even genuine pathos, invisible in its usual setting, in a song beginning:

If you like to gamble, I tell you I'm your man
You win some, lose some, it's all the same to me
The pleasure is to play, it makes no difference what you say
I don't share your greed, the only card I need is...

Friday 29 October 2010

Against Sass on delusional atmosphere

Whilst the bulk of Paradoxes of Delusion concerns the idea the relation between schizophrenia and solipsim, a later chapter provides a distinct line of interpretation of the specific schizophrenic symptom: delusional ‘atmosphere’ or ‘mood’ described by Jaspers in his General Psychopathology.

“The environment,” says Jaspers “is somehow different – not to a gross degree – perception is unaltered in itself but there is some strange change which envelops everything with a subtle, pervasive and strangely uncertain light.” Whatever is perceived may seem tremendously specific and meaningful, but without the patient being able to explain why; unfamiliar events and objects may appear to be copies or repetitions of themselves… “objects and events signify something but nothing definite”. [Sass 1994: 97]

The key feature of delusional mood or atmosphere is its uncanny particularity and Sass looks to some passages in Wittgenstein’s Brown Book to attempt to shed light on it.

In Schreber’s Memoirs, the feeling of uncanny particularity emerges most clearly in his discussion of the wasp miracle…”I have most stringent and convincing proof that these beings do not fly towards me by accident…. These animals always appear on definite occasions and in definite order around me.” It seems, rather, that Schreber’s experience of definiteness simply could not have been described more completely. [ibid: 99]

This description presents a problem, however. If that is the best that Schreber can do he does not seem to have given an account of the content of the experience. Just what can he mean by ‘definite occasions and in definite order’? Presumably, another observer would notice nothing special in the flight of the wasps and Schreber does not explain the pattern that he sees. So, as Sass asks, how can we characterise or comprehend this experience in which everything looks so completely normal yet at the same time so indescribably, so incomprehensibly, special?

His idea is to make use of some passages from the Brown Book in which Wittgenstein examines the idea that grasp of meaning is a particular kind of experience. This provides a key tool for Sass’ purpose. Wittgenstein sketches a distinction between a transitive and an intransitive meaning of ‘particular’.

Now the use of the word “particular” is apt to produce a kind of delusion and roughly speaking this delusion is produced by the double usage of this word. On the one hand, we may say, it is used preliminary to a specification, description, comparison; on the other hand, as what one might describe as an emphasis. The first usage I shall call the transitive one, the second the intransitive one. Thus, on the one hand I say “This face gives me a particular impression which I can't describe”. The latter sentence may mean something like: “This face gives me a strong impression”. These examples would perhaps be more striking if we substituted the word “peculiar” for “particular”, for the same comments apply to “peculiar”. If I say “This soap has a peculiar smell: it is the kind we used as children”, the word “peculiar” may be used merely as an introduction to the comparison which follows it, as though I said “I'll tell you what this soap smells like:...”. If, on the other hand, I say “This soap has a peculiar smell!” or “It has a most peculiar smell”, “peculiar” here stands for some such expression as “out of the ordinary”, “uncommon”, “striking”. [Wittgenstein 1958: 158]

So a transitive use of ‘particular’ introduces a comparison what can then be filled out. An intransitive use marks, instead, a mere emphasis, equivalent to saying that something is striking. Wittgenstein goes on to suggest that we can become confused as to the nature of the use that we ourselves are making of it at any time. This enables Sass to suggest that one can have an experience characterised by one kind of use and confuse it for one characterised by the other such that ‘when one is having the first, intransitive type of experience, that one is noticing the sort of thing that one actually does notice in the first, transitive type’ [104]. And from this Sass concludes:

As Wittgenstein analyses it, this uncanny experience of mute particularity is one of the characteristic delusions engendered by a certain unnatural, reflective stance characteristic of philosophizing. [104]

The problem with this approach is that it relies on the idea that Wittgenstein does indeed provide an analysis of an experience of mute particularity. But it is far from clear that he does. I say ‘far from clear that he does’ rather than ‘clear that he does not’ for this reason. Wittgenstein’s analysis, in the passages Sass cites, concerns the view that understanding sameness and difference of meaning can be explained or analysed as sameness and difference of an experience of meaning. It is the idea that the word ‘red’ comes to us in a particular way when we recognize a colour as red. It is to criticise this idea that Wittgenstein draws the distinction between transitive and intransitive meaning.

To shed light on this he compares the idea that one experiences a word in a particular way, with the idea that one might describe one’s bodily posture at any given time as ‘particular’.

You are, of course, constantly changing the position of your body throughout the day; arrest yourself in any such attitude (while writing, reading, talking, etc. etc.) and say to yourself in the way in which you say, “‘Red’ comes in a particular way …”, “I am now in a particular attitude.” You will find that you can quite naturally say this. But aren't you always in a particular attitude? [Wittgenstein 1958: **]

Although it is natural, he suggests, to say this when concentrating on one’s posture it is not that there is a type of posture being picked out. Neither, however, is one’s posture particularly striking.
And of course you didn't mean that you were just then in a particularly striking attitude.

Rather, the naturalness of the use of the word is an artefact of the situation:
What was it that happened. You concentrated, as it were stared at, your sensations. And this is exactly what you did when you said that “red” came in a particular way. [Wittgenstein 1958: **]

And this same idea is then used to try to undermine the compulsion to say that understanding a meaning is a matter of having a particular experience. There are experiences when one uses or understands a word just as one’s body is always in some posture or other. But nothing significant follows from this:
What is particular about the way “red” comes is that it comes while you’re philosophizing about it, as what is particular about the position of your body when you concentrated on it was concentration. We appear to ourselves to be on the verge of giving a characterization of the “way” describing the way, whereas we aren’t really opposing it to any other way. We are emphasizing, not comparing, but we express ourselves as though this emphasis was really a comparison of the object with itself; there seems to be a reflexive comparison. [Wittgenstein 1958: **]

The reason for looking at the thrust of Wittgenstein’s argument here is this. As is typical of his later work, there is a mix of both therapeutic understanding and destructive criticism. For Sass’ project to work, it would be necessary that part of the therapeutic understanding was an account of what it is or would be to have an experience of ‘mute particularity’ even if this were then criticised as part of the destructive aspect of Wittgenstein’s analysis. But it does not seem that that is the case. The closest that he comes to that is the account of the misleading naturalness of using the word ‘particular’ in the context of concentration. But in the elucidatory but deflating example of bodily posture the natural utterance, whilst intransitive, does not even mean striking. Whilst natural the utterance still, in some sense, misfires. So there is no suggestion that it expresses an experience of mute particularity and thus no account of that supposed experience is given.

This is, perhaps, unsurprising. Wittgenstein puts talk of ‘particular experiences’ in the mouth of an interlocutor who wishes to explain meaning through characteristic experiences and which he – Wittgenstein – wishes, by contrast, to refute. The more the quest for empathic and therapeutic understanding of the opposing view were to succeed in granting it coherence, the less robust would be the critical counterpoint. Instead, Wittgenstein offers the most minimal account of why one might be tempted to deploy the idea of ‘particular experiences’ and then pulls the rug from under it, leaving no substantial account of what such experiences might be.

For this reason, Sass’ suggestion that we look to where we should not look for an account of meaning to help us understand an experience of mute particularity cannot work.

Sass, L.A. (1994) The Paradoxes of Delusion, New York: Cornell
Wittgenstein, L. (1958) The Blue and Brown books, Oxford: Blackwell.