Thursday, 24 October 2024

Draft (to be co-authored) chapter on nursing skill acquisition (Dreyfus, Benner, Polanyi etc)

The role and nature of tacit knowledge in nursing practice 

Learning outcomes 

Readers will be able to: 

List some of the characteristics of skill acquisition across a range of practices. Set out some of the main differences between novices and experts according to the Dreyfus, Dreyfus and Benner model. 

Articulate some of the negative characteristics of expertise on the Dreyfus model: that is those things which expertise does not involve. 

Define very broadly ‘tacit knowledge’ and its contrast with explicit knowledge. 

Sketch a possible connection between tacit knowledge and practical know-how. 

Assess some of the answers to the question of why nursing is taught both theoretically and practically and the question of whether what is taught in these two ways is fundamentally distinct or the same but under different aspects. 

Summary of key points 

Nursing is taught both formally in lecture halls and practically and experientially in clinical settings such as wards. This raises the question of the connection between these two modes of learning and the nature of the knowledge and skills acquired. 

The five-step model from novice to expert developed by Dreyfus, Dreyfus and Benner provides one answer which privileges hands-on experiential learning for the development of expertise. 

However, the Dreyfus model yields an implausibly thin account of expertise disconnected from theoretical knowledge of rules and concepts and even from thought. 

An alternative account can be developed using Polanyi’s concept of tacit knowledge. 

A plausible account of tacit knowledge is that it is context-dependent and practical but, like explicit or theoretical knowledge, conceptually structured. Hence theoretical and practical aspects of nursing share a common conceptual structure. 

Introduction

Nursing is both a theoretical and a practical discipline. In the UK, qualification to become a registered nurse involves a university degree-level course or a top-up registered nurse degree apprenticeship. Other nursing roles are available such as nursing associates. But, since 2013 all new registered nurses have to hold a nursing degree with standards set by the Nursing and Midwifery Council. This is a recognition of the increasing importance of theoretical knowledge and analytic abilities to the practice of nursing.

However, a key component of the relevant education and training, alongside lecture-based teaching, is hands-on practical experience on hospital wards and in other clinical settings. This raises the question of the relation between these two ways of leaning or, perhaps, two forms of expertise. It prompts other, subsidiary questions such as whether it is merely a contingent matter that nursing is taught this way. Is the same knowledge taught both theoretically and practically or are there different forms of expertise?

This chapter will look at two different approaches to these questions via two different approaches to nursing expertise.

One is the model of expertise developed by Hubert and Stuart Dreyfus (eg Dreyfus and Dreyfus 1980) and promoted within nursing by Patricia Benner (Benner 1984). The other is a view of tacit knowledge, drawing on, but distinct from, the work of Michael Polanyi. While the Dreyfus and Dreyfus model suggests the primacy of practical, situation-specific expert judgement, developed on the ward, the latter approach helps to show that both practical and theoretical knowledge have a common structure. It explains more clearly how nursing involves putting theoretical knowledge into practice and thus explains how it can be a unified discipline requiring both formal and practical learning.

The Dreyfus and Dreyfus model of skill acquisition: from novice to expert

In the 1970s, Hubert Dreyfus, a philosopher, and his brother Stuart, a mathematician, developed a five-stage model of the development of expertise. On the basis of some of their unpublished papers, Patricia Benner, a professor of nursing, applied the model to developing nursing skills. The Dreyfus brothers based the model on:

the skill-acquisition process of airline pilots, chess players, automobile drivers, and adult learners of a second language and observed a common pattern in all cases… After we developed our five-stage description, a group of research nurses who had amassed considerable data about the acquisition of nursing skill found our model fitted their data very well. The results of that study may be found in the book From Novice to Expert by Professor Patricia Benner (Benner 1984). (Dreyfus and Dreyfus 1986: 20)

The model is thus empirically based but, as will be described below, is also heavily influenced by Hubert Dreyfus’ philosophical views, views that will be contested.

The five stages of the model comprise: 

  1. Novice 
  2. Advanced beginner 
  3. Competent 
  4. Proficient 
  5. Expert 

 As Benner explains,

These different levels reflect changes in three general aspects of skilled performance. One is a movement from reliance on abstract principles to the use of past concrete experience as paradigms. The second is a change in the learner's perception of the demand situation, in which the situation is seen less and less as a compilation of equally relevant bits, and more and more as a complete whole in which only certain parts are relevant. The third is a passage from detached observer to involved performer. The performer no longer stands outside the situation but is now engaged in the situation. (Benner, 1984, p. 13)

In principle, if these general aspects were independent and each had two or three possible values (as it transpires they do), this would yield many more than five possible levels. But, according to Dreyfus and Dreyfus, and also Benner, they are typically not independent and empirical study yields five characteristic stages in learning skills, from novice to expert.

For the purposes of this chapter, it will be sufficient to characterise the model by outlining the first and last stage as this gives the clearest contrast. The general trajectory is moving from the novice’s explicit consultation of general and context-independent rules to the expert’s ability to read a situation correctly and see, even without conscious decision, what needs to be done. The gradual move from novice to expert is a move from rule-governed deliberate behaviour to an intuitive grasp of a situation and the actions it calls for.

Stuart Dreyfus describes the novice stage, illustrated by the cases of learner drivers and chess players, as follows.

Normally, the instruction process begins with the instructor decomposing the task environment into context-free features that the beginner can recognize without the desired skill. The beginner is then given rules for determining actions on the basis of these features, just like a computer following a program.
The student automobile driver learns to recognize such domain-independent features as speed (indicated by the speedometer) and is given rules such as shift to 2nd gear when the speedometer needle points to 10. The novice chess player learns a numerical value for each type of piece, regardless of its position, and learns the following rule: Always exchange if the total value of pieces captured exceeds the value of pieces lost…
But merely following rules will produce poor performance in the real world. A car stalls if one shifts too soon on a hill or when the car is heavily loaded; a chess player who always exchanges to gain points is sure to be the victim of a sacrifice by the opponent who gives up valuable pieces to gain a tactical advantage. The student needs not only the facts but also an understanding of the context in which that information makes sense. (Dreyfus 2004: 177)

Benner gives a very similar description of novice nurses.

Beginners have had no experience of the situations in which they are expected to perform. To give them entry to these situations… they are taught about the situations in terms of objective attributes such as weight, intake and output, temperature, blood pressure, pulse, and other such objectifiable, measurable parameters of a patient’s condition – features of the task world that can be recognised without situational experience. (Benner 1984: 20-1)

They are also taught rules to guide their clinical practice, which can also be understood in advance of any particular clinical experience. This is common to the initial stages of learning any skill. A learner driver may be taught the mantra: ‘mirror, signal, manoeuvre’ and may typically even say this aloud when first driving. An expert driver, typically, will not and may, in some situations, rightly disregard the rule if in some emergency following it is more dangerous than breaching it. More generally, they will no longer explicitly think of the rule as they drive. As Benner says, the rule-governed behaviour of a novice is ‘extremely limited and inflexible’ (ibid: 21). Developing expertise, by contrast, is learning a more flexible response to situations and transcending action-guiding rules.

As long as the beginner pilot, language learner, chess player, or driver is following rules, his performance is halting, rigid, and mediocre. But with mastery of the activity comes the transformation of the skill which is like the transformation that occurs when a blind person learns to use a cane. The beginner feels pressure in the palm of the hand which can be used to detect the presence of distant objects such as curbs. But with mastery the blind person no longer feels pressure in the palm of the hand, but simply feels the curb. The cane has become an extension of the body. (Dreyfus and Dreyfus 1977: 12 cited by Benner 1984: 33)

Benner suggests that an expert nurse’s use of clinical tools and instruments is similarly transformed.

Reflection: Is the sketch of the resources deployed early stages of skill developed accurate? And is the charge that these resources produce poor performance plausible?

Contrasting the full expert with the stage immediately before it – proficiency – Stuart Dreyfus describes the immediacy of an expert’s appraisal of a situation.

The proficient performer, immersed in the world of his or her skilful activity, sees what needs to be done but decides how to do it. The expert [by contrast] not only sees what needs to be achieved; thanks to his or her vast repertoire of situational discriminations, he or she also sees immediately how to achieve this goal. Thus, the ability to make more subtle and refined discriminations is what distinguishes the expert from the proficient performer. Among many situations, all seen as similar with respect to plan or perspective, the expert has learned to distinguish those situations requiring one reaction from those demanding another... This allows the immediate intuitive situational response that is characteristic of expertise. (Dreyfus 2004: 179-80 italics added)

This passage exemplifies the three aspects that change as a skill is developed, as set out by Benner earlier. There is, first, a movement from reliance on context-free general rules to the use of past experience of previous real clinical situations. Second, the expert sees the situation as a whole as structured in some particular salient ways. Not every aspect of it is equally important for a clinical intervention. Third, the expert experiences themselves as part of the situation. Just as those familiar with the use of a cane feel the ground beneath it rather than the handle in their hand, so the expert driver experiences themselves not as driving a car but as driving. They construe their actions not as the turning of a steering wheel (which has such and such causal effects) but as changing lanes. This immediacy explains the contrast with the merely proficient performer who sees the situation, first, and only then decides how to respond. On the Dreyfus model of expertise, reading the situation correctly involves knowing what has to be done immediately.

This final characterisation corresponds to Aristotle’s idea of ‘phronesis’, or practical wisdom, itself a concept increasingly being applied to medical practice (Aristotle 1985; Boudreau et al 2024). Phronesis is a kind of practical knowledge applied by Aristotle mainly to moral expertise. The idea is that a skilled moral agent with phronesis sees the moral demands that situations make on them, on the actions they must thus carry out, as part of their experience of the situation itself. Their experience of the situation is not value-free but ‘fraught with ought’ (Sellars 1991: 212). The Dreyfus view of expertise in general is like that.

Reflection: Can you see how expertise contrasts with novice performance across the three aspects Benner lists? What if anything is the role of rules for expert practice on this account?

It is tempting to think of the transition from novice to expert as a matter of internalising rules. The learner may consult a manual of instruction, or a memorised mantra such as ‘mirror, signal, manoeuvre’, or they may explicitly infer such rules for themselves from taught examples, while the expert has mastered them to such an extent that they have become subconscious. The philosopher Mark Wrathal describes this as the ‘traditional picture’. But the Dreyfus picture is more radical.

[O]n the traditional model, the same rules govern the actions of the beginner and the expert alike. Learning is thus thought of as coming to understand the rules which govern behaviour—of beginning with an acquaintance with specific cases and learning through experience to abstract out of those specific cases general rules which are followed in all skilful action. But the phenomenology of skill acquisition shows that learning in fact moves in the other direction—from abstract rules to the recognition of particular cases. By the time one becomes an expert in a domain, one has an intuitive ability to recognize and respond to highly particularized situations and, unlike the beginner, is in no sense applying rules at all. (Wrathall 2014: 6)

To assume that the rules we once consciously followed become unconscious is like assuming that, when we finally learn to ride a bike, the training wheels that were required for us to be able to ride in the first place must have become invisible. (Dreyfus 2014: 111)

This rejection of the role of rules also highlights the priority that the Dreyfus model ascribes to hands-on, on the ward, experience over lecture-based learning, or as Benner puts it: the distinction between the novice level ‘skilled performance that can be achieved though principles and theory learned in a classroom and the [expert-level] context-dependent judgements and skill that can be acquired only in real situations’ (Benner 1984: 21).

Benner provides some qualitative social science empirical evidence that the five stage model of progress from novice to expert fits, very well, the experiences of at least some nurses. Further, it fits the anecdotally widespread experience of student nurses who find it difficult to value academic lectures once they have had their first experience of placement. The latter can seem more real and relevant. But it is worth digging a little deeper into how Hubert Dreyfus, at least, characterises the expert stage to assess whether it is a plausible description of expertise, after all.

Reflection: Can you summarise the nature of expertise on the Dreyfus model? With what does expert practice contrast? Hint: it may help to look again at the aspects Benner lists.

What is the nature of expertise on the Dreyfus model?

One of Hubert Dreyfus’ motivations to reject the role of rules, even internalised rules, for expertise, is a philosophically-based criticism – in 1999 – of the prospects of Artificial Intelligence (AI). He illustrates the general challenge for AI by considering an apparently simple abstract task: programming a machine to select a red square from a multicoloured array of geometrical figures. Assuming that on an AI approach there must be a set of instructions or rules that fully capture the expertise involved in the task, Dreyfus considers what they might be. One might instruct a child, for example, to ‘listen to the instructions, look toward the objects, consider the shapes, make your selection’ (Dreyfus 1999: 175). But the AI approach requires more detailed instructions sufficient, for example, for identifying a square rather than a circle.

One might say: ‘Count the sides; if there are four, it is a square.’ And what about the instructions for identifying a side? ‘Take random points and see if they fall on a line which is the shortest distance between the end points,’ and so on. And how does one find these points?... ‘But you unconsciously see points and unconsciously count.’ But do you? And why do the instructions stop here and not earlier or later? (Dreyfus 1999: 175)

The underlying problem highlighted in this example is that of knowing which general rule applies to a particular case. While we know that if something is a red square then it is red and a square and if it is square then it has four equal sides, these inferences unpack our prior mastery of the concepts. The challenge of AI is to explain how such general concepts apply to particular cases: cases which are all alike in being red and square but potentially unlike in all sorts of other ways such as size, location in space and time, orientation etc. The attempt to explicate a general rule – such as the rule-governing ‘square’ – using further rules appears to initiate a vicious regress. What rules guide the application of all the subsequent rules?

Dreyfus suggests that this regress can be blocked by an appeal to situations, the same concept he applies to human experts.

Whatever it is that enables human beings to zero in on the relevant facts without definitively excluding others which might become relevant is so hard to describe that it has only recently become a clearly focused problem for philosophers. It has to do with the way man is at home in his world, has it comfortably wrapped around him, so to speak. Human beings are somehow already situated in such a way that what they need in order to cope with things is distributed around them where they need it, not packed away like a trunk full of objects… (Dreyfus 1999: 260)

Thus a philosophical objection applied to the idea of modelling intelligence in some general formal programmable AI rules informs Dreyfus’ rejection of the role of rules in describing human expertise. Stuart Dreyfus summarises this view thus:

[A] beginner calculates using rules and facts just like a heuristically programmed computer, but… with talent and a great deal of involved experience, the beginner develops into an expert who intuitively sees what to do without recourse to rules. The tradition has given an accurate description of the beginner and of the expert facing an unfamiliar situation, but normally an expert does not calculate. He or she does not solve problems. He or she does not even think. He or she just does what normally works and, of course, it normally works. (Dreyfus 2004: 180)

This suggests that on the Dreyfus and Dreyfus model, a expert does not follow rules – except on occasions where unfamiliarity undermines their expert status and they are forced to – nor do they even think. Hubert Dreyfus makes two other striking claims: the expert does not act for reasons nor is their action informed by concepts.

[P]hronesis shows that socialization can produce a kind of master whose actions do not rely on habits based on reasons to guide him. Indeed, thanks to socialization, a person’s perceptions and actions at their best would be so responsive to the specific situation that they could not be captured in general concepts. (Dreyfus 2014: 110 italics added)

[A]lthough many forms of expertise pass through a stage in which one needs reasons to guide action, after much involved experience, the learner develops a way of coping in which reasons play no role. (Dreyfus 2014: 112 italics)

Dreyfus suggests that if, after the fact, such an expert is asked why they did as they did, they are only able to offer a ‘retroactive rationalisation’ that draws on what they recall of the less expert stage of being a mere ‘competent performer’. Following that reconstruction would ‘not exhibit expertise but mere competence’ (ibid: 113). Hence expertise does not seem compatible with what can be articulated as reasons, described as rules or even consciously entertained as thought. The space of expert actions is one shared by: ‘Animals, paralinguistic [ie cooing and babbling] infants, and everyday experts’ (ibid: 118).

Such a picture of expertise emphasises a dramatic contrast between what can be achieved through learning in the lecture theatre or classroom and what is achieved through experience in clinical settings. It may even appeal to those students of nursing who suspect that nothing of value is taught in the lecture theatre! Only the latter underpins expertise but at the cost of jettisoning what was achieved in the former. Whatever the descriptive power of the Dreyfus and Dreyfus, and Benner, five-stage model of acquiring nursing expertise, there is something badly wrong with its understanding of expertise. It reduces it to the unthinking, reasonless and thoughtless action of a babbling baby. Might there be a better account?

Tacit knowledge: Polanyi’s introduction

To recapitulate: the motivating question for this chapter is why nursing is taught both through formal lectures and experiential learning. The Dreyfus model suggests an answer which explains the role of the latter in developing expertise but at the cost of playing down the role of the former. An alternative answer, the subject of this second half, is that nursing involves both explicit and tacit knowledge, the latter being acquired experientially, but both forms of knowledge are unified by their conceptual structure.

The very idea of tacit knowledge was promoted in the second half of the twentieth century by the chemist turned philosopher Michael Polanyi. (Polanyi himself talks of tacit knowing rather than knowledge though that nuance will not matter here.) He gives the following 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)

This is an instance of what he takes to be a general phenomenon. Indeed, he begins his book The Tacit Dimension with the following bold claim:

I shall reconsider human knowledge by starting from the fact that we can know more than we can tell. (ibid: 4)

The broad suggestion is that knowledge can be tacit when it is, on some understanding, ‘untellable’. ‘Tellable’ knowledge is a subset of all knowledge and excludes tacit knowledge. But the slogan is gnomic. Does it carry, for example, a sotto voce qualification ‘at any one particular time’? Or does it mean: ever? Further, the very idea of tacit knowledge presents a challenge: it has to be tacit and it has to be knowledge. But it is not easy to meet both conditions. Emphasising the tacit status, threatens the idea that there is something – some content such as a fact – known. Articulating a knowable content, that which is known by the possessor of tacit knowledge, risks making it explicit (since the subject knows that…).

Reflection: Is the idea of tacit knowledge even possible? That is, might it be a contradiction of terms to think that there could be anything known which could not be put into words?

There is a second strand in Polanyi’s work which helps address this problem. At the start of his book Personal Knowledge he says:

I regard knowing as an active comprehension of things known, an action that requires skill. (Polanyi 1958: vii)

These two features suggest a way to understand tacit knowledge: it is cannot be made linguistically explicit and is connected to action, the practical knowledge of a skilled agent. The latter connection suggests a way in which tacit knowledge can have a content: as practical knowledge of how to do something. Taking tacit knowledge to be practical suggests one way in which it is untellable. It cannot be made explicit except in context-dependent practical demonstrations. It is not that it is mysteriously ineffable but that it cannot be put into words alone.

Polanyi also compares the example of recognition (already mentioned above) to a practical skill, likening it to bicycle riding:

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)

In both cases, the ‘knowledge-how’ depends on something which is not explicit: the details of the act of bike riding or raincoat recognition. While one can recognise one’s own macintosh, one is, according to Polanyi, ignorant, in some sense, of how. Thus how one recognises it is tacit. Many of Benner’s examples of nursing expertise are also recognitional: judging the state of health or illness of a patient.

In the passage above, Polanyi suggests that explicit recognition of something as an instance of a type is based on the implicit recognition of subsidiary properties of which one is ‘focally ignorant’. He explains the distinction of focal and subsidiary awareness using the example of focusing attention on what a pointing finger points to. In looking from the finger to the object, the object is the focus of attention whilst the finger, though seen, is not attended to. One attends from the proximal finger to the distal environment.

One of the quotations from Dreyfus and Dreyfus above is similar. The blind person who is an expert using their cane: ‘no longer feels pressure in the palm of the hand, but simply feels the curb’. They attend from whatever feelings there are in the hand to the state of the ground at the other end of the cane. Polanyi argues that tacit knowledge always has this ‘from-to’ structure.

If this were correct, all explicit knowledge would depend on something tacit, something ‘subsidiary’. But it is not clear that this is true.

Reflection: Is the suggestion above that Polanyi’s ‘from- to’ structure does not apply across the board plausible? Think, again, about Polanyi’s example of recognising a face.

Polanyi seems to assume that the question of how one recognises something always has an informative answer and then, to cover cases where it is not obvious what this is, he suggests it can be tacit. But, firstly, whilst it sometimes may have an informative answer, there is no reason to think that it always has (cf recognising that a square is red). Secondly, even in cases where one recognises a particular as an instance of a general kind in virtue of some further properties and cannot give an independent account of those properties, it is not clear that one need be focally ignorant of them. It may be, instead, that the awareness one has of the ‘subsidiary’ properties is simply manifested in the act of recognition. One might say, “I recognise that this is a, or perhaps my, macintosh 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. Whilst it seems plausible that one might not be able to say in context-independent terms just what it is about the sleeve that distinguishes a macintosh from any other kind of raincoat (one may, for example, lack the vocabulary of fashion or tailoring) that need not imply that one is focally ignorant of, or not attending to, just those features that make a difference. Recognition may depend on context-dependent or ‘demonstrative’ elements, such as recognising shapes or colours for which one has no prior name. But if anything, that suggests one has to be focally aware, not focally ignorant, of them.

Thus Polanyi’s own account of the tacit nature of recognition faces objections. But such criticism suggests the possibility of a more minimal account of tacit knowledge.

A minimal account of tacit knowledge

Recognition, such as recognition of a diagnostic type, is tacit because it is a skill – for example, developed through repetition and critical practice and demonstrated in applications in much the way that Dreyfus emphasises – and because it can thus be articulated only in context-dependent terms such as ‘like this!’. It cannot be explicated in words alone independently of additional practical demonstrations in context.

This distinction between tacit and explicit knowledge is reflected in the contrast between the ability to recognise colours and shades that most people have and their limited general knowledge of the names for colours. For most people, the ability to recognise, think about and recall (at least for some period) particular shades of colour goes beyond what they can make explicit linguistically. The ability can instead be manifested by pointing to particular instances of colour themselves. By contrast with the fine discriminations that can be made in the presence of actual colours and shades, context-independent general colour vocabulary is vague.

Similarly, by contrast with the context-dependent discriminations of skilled clinicians made in the presence of their patients, the criteria set out in diagnostic manuals are often vague. Because they are fully linguistic, the criteria in DSM and ICD, for example, are context-independent or general (American Psychiatric Association 2013; World Health Organization 1992). There is an advantage in communication of a linguistic codification of diagnosis that floats free of particular inter-personal relations. But it is bought at the cost of precision. By contrast, the features that play a role in diagnoses made be skilled clinicians are identified in the presence of a particular patient’s or client’s psychological or physiological whole. Such recognition cannot be captured in words alone.

So far, this minimal account of tacit knowledge captures the importance that the Dreyfus bothers and Benner place on practical learning but without reducing such expertise to a merely animal, mindless and conceptless ability. But without going as far as they do to downplay the role of language and reasons, this account, too, promises to show the importance of the tacit dimension. The best way to show this is via a detour into an example that the famous twentieth century philosopher Ludwig Wittgenstein uses. It concerns an explicitly abstract, general, context-independent and general rule.

Wittgenstein considers teaching a pupil to continue a mathematical series correctly who ‘judged by the usual criteria…  has mastered the series of natural numbers’ and is then taught to continue series of the form 0, n, 2n, 3n, etc. for arbitrary values of n but then goes wrong.

Then we get the pupil to continue one series (say “+ 2”) beyond 1000 – and he writes 1000, 1004, 1008, 1012.
We say to him, “Look what you’re doing!” – He doesn’t understand. We say, “You should have added two: look how you began the series!” – He answers, “Yes, isn’t it right? I thought that was how I had to do it.” —– Or suppose he pointed to the series and said, “But I did go on in the same way”. – It would now be no use to say, “But can’t you see…?” – and go over the old explanations and examples for him again. In such a case, we might perhaps say: this person finds it natural, once given our explanations, to understand our order as we would understand the order “Add 2 up to 1000, 4 up to 2000, 6 up to 3000, and so on”.
This case would have similarities to that in which it comes naturally to a person to react to the gesture of pointing with the hand by looking in the direction from fingertip to wrist, rather than from wrist to fingertip. (Wittgenstein 2009: §185)

The pupil described here reacts in a divergent way (from us) to explanations of how to continue. He appears to have acted under a divergent interpretation of the expression of the rule. But if, to be successful, an explanation of a rule has to be correctly interpreted, then any expression of the interpretation might be subject to divergent understandings, whether explicitly stated in a symbolism or by examples.

“But how can a rule teach me what I have to do at this point? After all, whatever I do can, on some interpretation, be made compatible with the rule.” – No, that’s not what one should say. Rather, this: every interpretation hangs in the air together with what it interprets, and cannot give it any support. Interpretations by themselves do not determine meaning. (Wittgenstein 2009: §198)

Since any interpretation has to be specified in some way, if understanding depends on an interpretation, no specification would be sufficient in itself. Hence the concept of the ‘regress of interpretations’.

Reflection: Imagine a game in which one player tries to explain with complete clarity the rule for adding 2 and the other player has to find some way to misunderstand the instructions prompting the first player to add more instructions. Try it!

There is, however, a more promising way to respond to Wittgenstein’s regress argument which connects it to tacit knowledge. The moral of the regress of interpretations according to the philosopher John McDowell is that:

We learn that it is disastrous to suppose there is always a conceptual gap between an expression of a rule and performances that are up for assessment according to whether or not they conform to the rule, a gap that is made vivid by saying the expression of the rule stands there… We must not acquiesce in the idea that an expression of a rule, considered in itself, does not sort behaviour into performances that follow the rule and performances that do not. (McDowell 2009: 100-101)

This, according to McDowell, is the moral of §201 of the Philosophical Investigations: ‘there is a way of grasping a rule which is not an interpretation, but which, from case to case of application, is exhibited in what we call “following the rule” and “going against it”’ (Wittgenstein 2009: §201). For those who are party to the relevant practices, there is no gap between the expression of the rule and being told which way to go. A signpost, for example, not merely a signpost under an interpretation, points the way. On this account, the regress of interpretations is stopped before it can start. Hence, the expression of a rule is explicit in its directions.

But it is only explicit for those with the right eyes to see, or ears to hear, an explanation: for those, in Stanley Cavell’s phrase, who share the ‘whirl of organism’ of our form of life (Cavell 1969: 52). This in turn grounds out in the applications of rules, which are context-dependent, conceptually-structured and practical. The regress of interpretations argument shows that any informative explanation of what following a rule correctly, going on in the same way, comprises soon gives out. Any general account of the relation of rules or conceptual generalities to particular judgements falls prey to the regress of interpretations. What can be made explicit in words or rules rests on the tacit because going on in each specific way simply is accord with a rule or concept. It is also context-dependent and, since it links conceptual generalities to particular cases in judgements, it is practical.

Because the relation of the tacit and explicit is subtle, it is worth giving a worked example. It is possible to make a béchamel sauce by following a recipe: to measure ingredients and to cook at a specific temperature for a predetermined time. But it is also possible to make one ‘bi t’rack o’ t’ee’ (by the reckoning of the eye) as it is said in Yorkshire dialect. One judges a rough equivalence of butter and flour, sautés the resultant roux until it looks right (so as to cook the flour) and then adds milk gradually and intermittently while stirring continually, watching the consistency fall to almost that of the added milk and then stiffen again. Gradually, the rate of returning to stiffness slows. Were one to add too much milk, it would never thicken again. Thus, the end point is fixed by a judgement that the rate of stiffening has slowed sufficiently that a final addition of a particular amount of milk will, combined with the residual heat energy of the sauce, yield the right consistency by the time it is served.

Preparing a béchamel sauce is thus an expression of a conceptual understanding of the effects of dilution, heating, stirring, thickening against the jeopardy of adding too much milk. But the expression of the concepts comprises demonstratives of the form ‘that degree of stiffness’ and ‘that quantity of additional milk’. It involves the right kind of manipulation of the sauce mixture with a spoon and the right degree of heat applied so that it bubbles thus. Although it is possible to make a béchamel sauce following an explicit recipe, the cook who makes it ‘by eye’ does so employing a form of conceptually-structured, context-dependent, practical knowledge, or tacit knowledge, on this account. Further, its expression and articulation in a practical demonstration depends for its success on the ability of the audience to see in the particularity of a few cases the generality of the rules involved. They must have ‘eyes to see’. They must share the ‘whirl of organism’.

The dual challenge for an account of tacit knowledge can be met in this way as follows. It is tacit because it cannot be codified in context-independent and general terms – it is in that sense ‘untellable’ – while at the same time it is knowledge because it is articulated in the application of general concepts to the particular case, grounded in practice, which is a form of know-how. One consequence of this account is that explicit knowledge always rests on a body of tacit knowledge.

The ward versus the lecture hall? Tacit and explicit knowledge

On the Dreyfus, Dreyfus and Benner account, expertise is a capacity shared with animals and prelinguistic children. It is an ability with little to do with reasons, thought or concepts. Thus what is learnt in practice on the ward supersedes what is learn in lecture halls. Although their five-step model of the acquisition of skills has some empirical plausibility, the detailed characterisation of expertise is implausible.

There is, however, a better picture. Experiential learning teaches tacit knowledge: knowledge that cannot be put into words alone because it is context-dependent and practical. Its demonstration requires practical application. Further, tacit knowledge underpins explicit knowledge even of such general and rule-governed concepts such as adding two. It remains, nevertheless, conceptually structured. And hence there is a common structure to tacit and explicit knowledge, to learning on the ward and in the lecture hall.

Nursing involves theoretical knowledge but also practical skills. On a correct understanding tacit knowledge for rational agents such as human adults is a genuine complement to explicit knowledge but also related to it. Both are deployments of conceptual judgement, one theoretical and one practical. The latter is a shaping of knowledgeable action. The skilled practitioner not only knows what to do in a practical case but they also know why, even though the reasons ground out in patient-specific judgments.

Further reading

The Heideggerian philosophical background of Hubert Dreyfus’s views is set out here:

Dreyfus, H.L. (1991) Being-in-the-World: A Commentary on Heidegger’s Being and Time, Division I, Cambridge, Mass.: MIT Press

For a book length examination of the nature of tacit knowledge see:

Gascoigne, N. and Thornton, T. 2013. Tacit knowledge. Durham: Acumen

For a critical discussion of Hubert Dreyfus’ account of expertise as skilled coping see:

Schear, J.K. (ed.) (2013). Mind, reason, and being-in-the-world: the McDowell-Dreyfus debate. New York: Routledge.

Relevant web pages

The Collaborating Centre for Values-Based Practice promotes discussion of knowledge of values in healthcare

http://valuesbasedpractice.org/

The International Network for Philosophy & Psychiatry promotes research on the philosophy of mental healthcare more broadly

http://inpponline.com/

The Polanyi Society is dedicated to promoting Polanyi’s views of tacit knowledge

http://www.polanyisociety.org/

References

American Psychiatric Association (2013) Diagnostic and Statistical Manual of Mental Disorders Fifth Edition (DSM-5), Washington, D.C.: American Psychiatric Association

Aristotle (1985) Nicomachean Ethics (translated by Irwin, T.), Indianapolis: Hackett

Benner, P. (1984) From Novice to Expert: excellence and power in clinical nursing practice, Menlo Park, California: Addison-Wesley

Boudreau, D., Wykretowicz, H., Kinsella, E.A. et al. (2024) Discovering clinical phronesis. Med Health Care and Philos 27, 165–179. https://doi.org/10.1007/s11019-024-10198-8

S. Cavell, (1969) Must We Mean What We Say?, Cambridge: Cambridge University Press

Dreyfus, H.L. (1999) What Computers Still Can’t Do, Cambridge, Mass.: MIT Press

Dreyfus, H.L. (2000) Responses. In Heidegger, Coping, and Cognitive Science (eds M. Wrathall and J. Malpas), pp. 313-349 .Cambridge, Mass.: MIT Press

Dreyfus, H.L. (2014) Overcoming the Myth of the Mental: How Philosophers Can Profit from the Phenomenology of Everyday Expertise in Dreyfus, H. L., & Wrathall, M.A. (2014) Skillful Coping: Essays on the Phenomenology of Everyday Perception and Action, Oxford: Oxford University Press

Dreyfus, H. L., & Dreyfus, S. E. (1977). Uses and abuses of multi-attribute and multi-aspect model of decision making. Unpublished manuscript, Department of Industrial Engineering and Operations Research, University of California at Berkeley.

Dreyfus, H. L., & Dreyfus, S. E. (1986). Mind over machine: The power of human intuition and expertise in the age of the computer. Oxford: Basil Blackwell

Dreyfus, S. E. (2004) The Five-Stage Model of Adult Skill Acquisition, Bulletin of Science, Technology & Society, 24: 177-181

McDowell, J. (2009) The engaged intellect. Cambridge, MA: Harvard University Press

Polanyi, M. 1962. Personal knowledge. Chicago: University of Chicago Press

Polanyi, M. 1967. The tacit dimension. Chicago: University of Chicago Press.

Sellars, W. (1991) Science, Perception and Reality. Atascadero: Ridgeview Publishing

Wittgenstein, L. 2009. Philosophical investigations. Oxford: Blackwell

World Health Organization (1992) The ICD- 10 Classification of Mental and Behavioural Disorders: Clinical Descriptions and Diagnostic Guidelines. Geneva: World Health Organization.

Wrathall, M.A. (2014) Introduction: Hubert Dreyfus and the Phenomenology of Human Intelligence in Dreyfus, H. L., & Wrathall, M.A. (2014) Skillful Coping: Essays on the Phenomenology of Everyday Perception and Action, Oxford: Oxford University Press: 1-22