What do Wittgenstein’s grammatical investigations reveal about the nature of psychological phenomena?

I. Introduction

In the Philosophical Investigations (2001) and elsewhere (Wittgenstein 1967, 1980, 1982),1 Ludwig Wittgenstein undertakes a detailed study of what he calls the ‘grammar’ of psychological concepts. This covers a wide range of phenomena, including ‘understanding’, ‘knowledge’, ‘sensations’, ‘emotions’, and so on — many, if not all, of which are often taken to refer to mental states or processes. In this essay I will show how, through his method of grammatical investigation, Wittgenstein challenges this preconception, which is present in much contemporary philosophy, psychology and science of the mind. In particular, I will concentrate upon a number of grammatical features of these concepts, namely: (i) the differences and ‘family resemblances’ between various psychological concepts, (ii) the asymmetry between their first and third person use, and (iii) the emptiness of the notion of a ‘private mental object’, which Wittgenstein claims arises from a mistaken application of the ‘picture’ of the inner and the outer. I will also consider various objections to Wittgenstein’s position, including materialism and behaviourism, before drawing some conclusions concerning the implications of his views for both philosophical and scientific investigation of the mind.

II. The Notion of a Grammatical Investigation

Throughout his later period, Wittgenstein emphasis the nature of his task, and that of philosophy in general, as being a ‘grammatical investigation’ (McGinn 1997: 12). The aim of such an investigation is not, as with conventional philosophical and scientific analyses, to ‘penetrate phenomena’
(pi §90), or reduce them to a set of necessary and sufficient conditions, but to ‘[clear] away misunderstandings’ ‘concerning the use of words’ (ibid). Wittgenstein’s goal is to identify and eliminate the root causes of philosophical confusion, which lies in our tendency to be ‘bewitched by language’ (pi §109) and ‘held captive’ by metaphorical ‘pictures’2 (pi §115) of how concepts operate, but that do not fit their actual use. Central to this technique is the abandonment of explanation in favour of description (pi §109), and a rejection of philosophical theorising and abstraction in general in favour of careful examination of particular cases and examples, and how they fit into ‘the stream of life’ (lw1 118). This approach, influenced as much by Goethe’s work on the morphology of plants (Goethe 1790) as by any philosophical tradition (Monk 1991: 303), is summed up in pi §66 with the instruction: ‘don’t think, but look!’.

On first sight, one might question the appropriateness of such a method for investigating psychological concepts, such as feelings, sensations, etc. After all, these are generally taken to be empirical phenomena, as studied by the a posteriori of the sciences of the mind, and not mere grammatical constructs (Goldfarb 1989). However, to simply assume this from the outset would be to commit exactly the sort of philosophical error that Wittgenstein’s method is intended to guard against. To take the structural similarity between the two sentences ‘I have a pain in my arm’ and ‘I have a handkerchief in my pocket’ as prima facie evidence of a deeper parallel between the two cases, i.e. that they describe physical possession of some kind of object is, according to Wittgenstein, to mistake the nature of the very phenomena that we seek to describe (‘[t]he decisive move in the conjuring trick’ which is ‘the very one that we thought quite innocent’ [pi §308]). Of course, it is conceivable that the notion of mental states and processes may have some basis in scientific fact. Even so, it is questionable whether these are the entities to which our psychological concepts refer, and to simply assume that this is the case is question-begging and potentially unsound. All that can be assumed from the outset is that we are dealing with a variety of distinct but related concepts, and not that these must as a matter of metaphysical necessity share any particular underlying nature or structure (as states or processes within the brain, for example). The main task of a grammatical investigation of psychological phenomena is therefore to understand the similarities and differences between these and other concepts (pi §130), and to remind us how they are used in practice (pi §117) in order to gain a clear, or ‘perspicuous’ (pi §122), view of language.

Wittgenstein’s non-standard use of the word ‘grammar’ also requires some explanation, since it clearly does not refer to the system of verbs, nouns, and so on that normally go by this name. In pi §664, Wittgenstein states that ‘[i]n the use of words one might distinguish “surface grammar” from “[deep] grammar”’.3 Adopting this terminology, we might say that ‘surface grammar’ is constituted by those syntactic rules and relationships that are internal to language, such as the familiar verb-noun or subject-verb-object structure of English sentences. On this notion of grammar, the sentence ‘[c]olourless green ideas sleep furiously’ (Chomsky 1957: 15) would be considered perfectly grammatical. Wittgenstein’s notion of ‘deep grammar’, however, covers what traditional philosophy of language would call semantics and pragmatics, or the way that our use of language is embedded within our various ‘forms of life’ (pi §241). As such, deep grammar reaches ‘outside’ of language, connecting words with their uses — i.e. their meanings — as well as to non-linguistic practices such as physical gesture, tone of voice and facial expressions (pi §21, §433, §537). A consideration of the deep grammar of the above sentence reveals it to be nonsensical since it has no use (as opposed to it being false due to there being no ‘colourful green ideas’ that are ‘sleeping furiously’).4 By observing the subtle differences between how the different ‘regions’ of our language operate, a grammatical investigation can clarify the various types and uses of concepts, replacing the Fregean ‘model of “object and designation”’ (pi §293) with a much richer and more flexible conception of the role of language within human affairs.

III. The Psychological Language-Game

Having outlined Wittgenstein’s methodology, I will now examine how it is applied with regard to psychological phenomena. In Zettel §472, Wittgenstein sketches out a ‘[p]lan for the treatment of psychological concepts’. This identifies many of the main characteristics of concepts that we class as psychological, including:

‘Psychological verbs characterized by the fact that the third person of the present is to be verified by observation, the first person not’

‘The first person of the present akin to an expression’

‘All have genuine duration’

‘Possibility of … simultaneous occurrence’

‘All have degrees and qualitative mixtures’

‘Place of feeling in the body…’

(ibid.)

Before considering these points in greater detail below, it is worth noting that Wittgenstein is not attempting to lay out a schema as to how psychological concepts are to be defined, but rather offering a ‘synoptic view’ (z §464) of the many and varied ‘family resemblances’ (pi §66) that hold between them. These are, in Wittgenstein’s sense of the word, the criteria by which we identify concepts as psychological, rather than an exhaustive ‘taxonomy’, as might be provided under a behaviourist or materialist account (Hilmy 1995: 236).

In the Philosophical Investigations, Wittgenstein cites the concept of a ‘game’ as being paradigmatic of terms that are understood by all competent language users, and yet are seemingly impossible to define in terms of necessary and sufficient conditions (pi §66).5 Instead, the meaning of ‘game’ is determined by a complex series of similarities, interconnections and ‘family resemblances’ that hold between activities that we call games, along with the use of paradigm cases or samples — team sports, games of skill, games of chance, etc. — around which these relations are clustered (pi §16, §69). Similarly, psychological concepts do not form a unified and consistent genus, but are united by a complex and overlapping series of similarity relations that hold between them. The concept of ‘knowledge’, for example, exhibits a different grammar to that of ‘pain’, which is a sensation concept and so has duration, intensity and physical location (z §485). Pain is itself differentiated from other sensation concepts, such as feeling warm or cold, which have no particular ‘characteristic expression’ (z §483), and from joy, which is difficult (although not necessarily impossible) to locate at a particular point in the body (z §486). For Wittgenstein, it is these grammatical distinctions that unite or differentiate psychological concepts, both from each other and from other concepts, and not necessarily any commonality in their underlying physiology (although neither is such commonality ruled out). This is true even of sensory modalities, i.e. touch, taste, hearing, sight and smell, whose similarity is justified in terms of their ‘analogies and connections’ (z §474), and not just the ‘logical criterion’ that ‘they give us knowledge of the external world’ (z §477). By highlighting these distinctions, Wittgenstein forces us to attend to the details of the role that they play within the psychological ‘language-game’, weakening the grip of the idea that there must be something common that ‘lies behind’ all of these concepts in terms of them fitting into the familiar model of states and processes (Donagan 1968: 349). For Wittgenstein, what ‘lies behind’ is not a mental state or process, but the practice of using a concept in a particular way.

This concept of a ‘language-game’ (Sprachspiel, pi §7) is referred to throughout Wittgenstein’s later philosophy and combines the family-resemblance structure of a game with Wittgenstein’s distinctive notion of grammar as an integral part of the ‘forms of life’ from which language takes its meaning. Thus a single sentence, such as ‘I am in pain’, may be used in many different ways: as an expression of pain substituted for an inarticulate cry (pi §244); to report a symptom — to a doctor, for example (Donagan op. cit. 326–7); as a form of pretence, as when lying to someone in order to elicit sympathy; and so on. Each of these constitutes a different, but interrelated, language-game within which the concept of ‘pain’ plays a part. As such, not just the meaning of the word but its context must be taken into account in order to determine the role that it plays within the language-game — and in many cases its meaning will depend upon its context.6 Some commentators (e.g. Mounce 2002: 77) have accused Wittgenstein of over- or misapplying the notion of a game, since not all concepts conform to this model. However, it is clear that Wittgenstein’s game analogy is not intended to be taken as a comprehensive model of how concepts operate, since natural language does not on his account have the ‘formal unity’ of a logical calculus (pi §107, §81).7 Rather, Wittgenstein is offering an alternate picture of how certain concept words function, and thus an antidote to the ‘crystalline purity’ (pi §108) of logic, through which many philosophers (notably Russell) have approached the philosophy of language.

IV. Mental States and Processes

In order to demonstrate the application of Wittgenstein’s method to the investigation of psychological phenomena, I will consider two examples: (i) understanding, which is often characterised as a kind of mental state or process, and (ii) pain, which is typically thought to refer to a specific bodily state, such as C-fibres firing (Kripke 1980: 98). Underlying both of these characterisations is the notion that thoughts, feelings, sensations, and so on, take place in a hidden ‘inner realm’ that is separate and distinct from the ‘external world’ of physical objects. This conceptual divide, which continues to exert considerable influence upon both the philosophy and science of mind, may be traced back at least to Descartes (1641), where it emerges in the form of the familiar mind–body problem. Wittgenstein seeks to ‘dissolve’ both this problem and the dualism to which it gives rise not by rehabilitating mental phenomena within the physical world, as per physicalism or materialism, but by questioning the aptness of the ‘picture’ of the ‘inner’ and the ‘outer’ phenomena in relation to psychological concepts (McGinn ibid. 27–9).

Wittgenstein first raises the question of understanding with reference to the primitive language-game of the builders in pi §2, asking ‘am I to say that [ostensive definition] effects an understanding of the word?’ (pi §6; my italics). The suggestion that understanding is not a mental process, but tied to the performance (or disposition to perform) an appropriate action is later taken up in the discussion of rule following in pi §§138–55. Here, Wittgenstein considers whether understanding could be something that occurs ‘in a flash’ (pi §138), such as when we suddenly grasp the meaning of a word, for example. Whilst the description accurately captures the phenomenology of the experience (at least in certain cases), Wittgenstein questions what precisely is it that comes before our minds in such a situation. It cannot be the use of the word, since this is extended in time, and not momentary (ibid.). And if the use of words is determined by their meaning, then how can what we grasp ‘in a flash’ ‘fit a use’ (pi §139), since the grammar of mental states is not something that can ‘fit or fail to fit’ in this way (ibid.)? The idea that a certain picture, application or interpretation of the word comes to mind is similarly problematic. Whilst understanding may often be accompanied by a picture or particular interpretation — a formula, for example — this cannot in itself constitute the understanding, since a picture can support many different applications (pi §141). Conversely, the picture or formula may be absent in another case where a person understands by different means, or where understanding is not accompanied by any picture or formula and yet they are still able to perform the appropriate action or use the word correctly (pi §151).

Here, Wittgenstein shifts away from considering the ‘hidden’ aspects of understanding to what is publicly displayed and accessible: the criteria of understanding (pi §143, 146). We say that someone has understood a word when they go on to use it in the usual way — i.e. in accordance with a practice. In cases where they, despite having felt that they understood, misuse the word (again, relative to our own practices and expectations) then we are ‘tempted to say that [they have] understood wrong’ (pi §143). Even when a person does go on to do what was expected, we may later find that they diverge from this norm, and so we would say that they had not understood after all (pi §145). Thus, it is always possible that what we took to be understanding might turn out otherwise, and vice versa, so attributions of understanding — like those of knowledge, whose grammar is similar (pi §150) — are always potentially defeasible.

The above considerations call into question the notion of understanding as a mental process or state, since processes and states can always be said to occur at a particular time and place and in a particular manner; e.g. the process of making tea, or the state of sleep. This is not obviously true of understanding, which cannot be said to start and stop along with the actions that it precipitates (pi §148). Also, as Wittgenstein points out, we have no ‘knowledge of the construction of the apparatus’ (pi §149) — i.e. the mind or soul — within which the process or state is supposed to take place, and yet this criteria for the use of state and process concepts does not appear to be present in (or relevant to) the case of ‘understanding’ (pi §153). What this shows is that the grammar of ‘understanding’ does not fit that of an inner state or process, but rather describes a set of circumstances to which we attach significance (pi §155). Whilst the criteria for attributing understanding may include the feeling of being able ‘to go on’ (pi §151), a flash of insight, or the presence of a formula or mental picture, there are possible circumstances in which each of these is lacking and yet we would still say that understanding was present. When we say ‘I thought I understood, but I was mistaken’, the decisive factor in determining whether understanding was in fact present is not to be found ‘in the head’ in the form of a state or process, but in the world in the form of the distinctive pattern of circumstances that constitute understanding.8 These are entirely public and not hidden from view in some inner realm, as we might otherwise suppose.

In Zettel §§608–11, Wittgenstein goes on to question the assumption that psychological concepts can necessarily be correlated with any kind of brain process. In z §608, he observes that in some cases, the relevant facts for the attribution of psychological phenomena may lie in the history of a subject, as opposed to their current physiological or neurological state. As such, it would be impossible to simply ‘read off’ (ibid.) their psychological state from their physical brain or body. A materialist might counter this with the suggestion that psychological concepts supervene upon a wider range of facts than just the subject’s current physiological state, thus taking into account historical and other contextually relevant facts. However, the range of facts that these concepts would need to supervene upon would be very wide indeed, extending to the linguistic practices of the speaker and their community, as well as to the ‘fact’ that the subject is capable of advanced cognitive feats — i.e. that it is a living being (cf. pi §250, §284; z §§520–1). Furthermore, as Goldfarb (1989: 641–2) suggests, even if we were to discover some neurological state that was correlated with, for example, the subject’s understanding of the word ‘manatee’, then it would be impossible for us to identify this with the relevant psychological phenomena due to the potentially infinite number of factors (contextual, historical, ruling out special cases such as lying, and so on) that would also need to be taken into account. Conversely, if the criteria for understanding were present without the neurological state, then we would still be inclined to say that the subject understood, thus demonstrating the inadequacy of the proposed identity relation. On this view, the relevant facts are just not amenable to ‘the models we have of states and processes in physical science’ (ibid. 642; cf. pi §308), and so no reductive account of psychological concepts — let alone a physiologically reductive one — can be given. This makes a materialist explanation of our everyday use of psychological concepts highly implausible due to the extreme complexity of such an account, even if were theoretically possible.

V. Privacy and Pretence

The grammar of ‘understanding’, which is a primarily cognitive and dispositional concept, may be contrasted with that of ‘pain’, which is primarily sensory and occurrent. The concept of pain covers a wide range of cases, including various kinds of bodily sensations and emotions, and is associated with certain characteristic forms of expression — crying out, flinching, etc. (z §483). Unlike understanding, pain is always located in a particular region of the body (z §482) and has both intensity and duration (z §472). Wittgenstein’s ‘[p]lan for the treatment of psychological concepts’ also notes the asymmetry between first and third person uses of sensation concepts. In the first person case, the use of such concepts is described as being ‘akin to an expression’, whilst in the third person, such concepts may be used to provide ‘information’ (ibid.). Wittgenstein’s notion of an ‘expression’ may be understood as a way of expressing pain — the verbal equivalent of a cry, for example (pi §244). On this view, the sentence ‘I am in pain’ may be a more articulate substitute for other more primitive forms of ‘pain-behaviour’, such as crying (ibid.), and is no more descriptive of a mental state than the word ‘ouch’. The same sentence may also be used to report symptoms, or tell a lie (pi 161e), as described above, each of which has its own distinctive context and criteria of application. Even the third person sentence ‘she is in pain’ need not be read as an ascription of a mental state since we might also use this as a description of pain-behaviour; e.g. when someone cries out unexpectedly, or to report a fact about another person, such as a doctor reporting a patient’s symptoms to a colleague. Together, these form an entire family of language-games involving the use of the word ‘pain’, the substantial nature of which has yet to be determined.

The asymmetry between first and third person use of psychological concepts arises due to the possibility of doubt, which may be present in the third person case, but not in the first person, since one cannot legitimately doubt whether one is in pain, regardless of how (or whether) one expresses it (pi §288). Furthermore, Wittgenstein rejects the idea that one has knowledge (pi §246) of one’s own pain, since in order for the concept of ‘knowledge’ to apply it must be possible that we could conceivably not know; i.e. there must be the possibility for discovery or doubt (pi §251). This does not apply to the first person use of the word ‘pain’ — ‘except perhaps as a joke’ (pi §246) — since it makes no sense to say ‘I am unsure if I am in pain’, or ‘I thought I was in pain, but I was mistaken’, in the way that I can be mistaken about the weather, for example (pi §288). Such statements are, in Wittgenstein’s sense of the word, grammatically incorrect (although such cases must be clearly distinguished from those in which one masks or ignores one’s pain). Conversely, I can know that another person is in pain precisely because it is possible for me to doubt it — although even this may be difficult to do ‘in a real case’ (cf. pi §303). Furthermore, in the third person case, it is possible that someone might intentionally set out to deceive others by enacting characteristic forms of pain-behaviour. This may range from a straightforward lie (‘That hurts!’) to an elaborate exhibition designed to fool the observer into thinking that the subject is in pain. However, on Wittgenstein’s account, ‘[l]ying is a language-game that must be learned like any other’ (pi §249). In particular, this cannot be taken as evidence for a private mental state or process in the case of genuine pain since the language-game of pretence is possible in most (if not all) human interactions. Indeed, without the possibility of concealing or feigning our thoughts, sensations and emotions, we would scarcely be tempted to think of them as inner states or processes at all (z  557).

The ‘surface grammar’ of sentences like ‘I have pain’, coupled with the possibility for error or pretence, tempts us to think of pain in terms of privileged knowledge of one’s ‘inner state’, as if ‘pain’ were the name of some kind of private mental object (pi §244, §257). On this account, someone who is feigning pain is thought of as exhibiting all of its outward signs (i.e. pain-behaviour) whilst lacking the requisite ‘inner state’ for genuine pain. Wittgenstein challenges this use of the object–designation model by drawing our attention to the distinctive grammar of the word ‘pain’ compared to that of non-mental states and processes. For example, the ‘criterion of identity’ (pi §253) for pain is such that I can have the same pain as you (indigestion, for example), and yet it would make no sense to say that you have my pain (ibid.). Moreover, we cannot learn pain through ostensive definition — the model of learning exemplified by Aquinas’s recollections in pi §1 — since we cannot ‘point’ to pain, but only to pain-behaviour. In order for a child to acquire the concept of pain, it must therefore master the language-game of which it forms a part, as opposed to learning what ‘pain’ refers to, since there is no such public referent. We should be equally careful of attributing any prior familiarly with a private mental object that is called ‘pain’, since in the absence of this concept and the grammatical distinctions that it entails, there is nothing to unite the various bodily processes and states under this banner.

The above emphasis upon outwardly visible behaviour and ‘criteria’ as opposed to inner states has led some philosophers to read Wittgenstein as denying the existence of such states altogether, or as defining ‘pain’ in terms of pain-behaviour, or dispositions towards it (cf. Donagan op. cit. 335). When Wittgenstein’s interlocutor raises the issue of behaviourism in pi §305 and §307 in the context of a discussion about remembering, Wittgenstein responds that ‘[w]hat we deny is that the picture of the inner process gives us the correct idea of the use of the word “to remember”’ (pi §305; my italics), and ‘[i]f I do speak of a fiction, then it is of a grammatical fiction’ (pi §307; original italics). The ‘grammatical fiction’ to which Wittgenstein refers is the notion that the word ‘pain’ need refer to an actual state or process in order to fulfil its role in the language-game. This is merely the application of a picture whose grammar has been shown not to fit our actual use of language. As Wittgenstein’s ‘beetle in a box’ analogy concludes, the object (i.e. the mental state) ‘drops out of consideration as irrelevant’ (pi §293) since it does not matter what each person has ‘in their box’ (i.e. their mind) in order for them to participate in the language-game. Indeed, the box may even be empty provided that the word continues to be used in the correct way — i.e. according to accepted practice. On this reading, Wittgenstein does not in any way deny the existence of mental processes, which he agrees are ‘not a nothing’ (pi §304), but rather is claiming that they are not required in order to play the language-game — i.e. they ‘are not a something’ either (ibid.). The only reason that we feel them to be necessary is because of our prior commitment to the ‘picture’ of inner states and processes to which we take our psychological concepts to refer. Once we set this picture aside, we find that all that is required for the practice of talking about ‘pain’ to function is the concept of pain (pi §301), and that even the language of ‘states and processes’ is inappropriate, since we have little or no conception of the underlying mechanisms to which the metaphor alludes (cf. pi §149).

VI. Conclusion

Wittgenstein’s grammatical investigation reveals a number of important features of psychological phenomena. Firstly, the relevant concepts exhibit a complex series of ‘family resemblances’, both within and between the various subcategories of knowledge, sensations, emotions, and so on, as opposed to comprising a single unified genus. Secondly, our use of these concepts does not entail the existence of any particular mental states and processes to which they correspond (although Wittgenstein does deny that such states and processes exist). Finally, the notion of a ‘private object’, to which we sometimes take our cognitive and sensation concepts to refer, does no work within the ‘language-game’ that comprises our everyday use of these concepts. Rather, it is ‘forced upon us’ by the application of certain ‘pictures’ of the way that language and psychological concepts are thought to operate. Chief among these are the ‘model of an “object and designation”’ (pi §293) and the picture of the ‘inner’ and the ‘outer’, which we mistakenly take to be supported by the asymmetry between first and third person uses of psychological concepts, and the possibility of pretence.

Perhaps some of the anxiety that we feel about these conclusions may be relieved when we consider that they do not rule out the existence of a purely causal link between mental states or processes and our behaviour (although this is not the relation of an object to its referent). Such states and processes undoubtedly play a major role in guiding and shaping both our actions and the constantly evolving ‘forms of life’ within which our language-games take place. Without them, we would have little or no cause to use such expressions as ‘understanding’ or ‘pain’, but this does not entitle us to infer that they are the entities to which our psychological concepts refer. In this respect, Wittgenstein draws a clear line between the purely physical, or causal, concerns of the sciences of the mind on the one hand, and the purely conceptual — i.e. grammatical — concerns of philosophy on the other. This dramatically reduces the extent to which the results of any a posteriori scientific investigation of mental phenomena can bear upon our understanding of psychological concepts, since there is no longer a clear point of contact or correspondence between the two.

——————

1 Hereafter abbreviated as pi, z, rp and lw, respectively.

2 The term ‘picture’ refers to the models, metaphors and assumptions that lie behind and guide our use of language, such as the model of an ‘object’ and its ‘designation’ (pi §293) or the notion of ‘inner’ and ‘outer’ phenomena. For Wittgenstein, such pictures are prior to language use, although in many cases, they — or the temptations to adopt them — are themselves are embedded within language (cf. pi §115). This underlines the need for careful cross-referencing and examination of multiple cases in order to prevent linguistic habits and prejudices from obscuring genuine grammatical distinctions.

3 Anscombe’s translation of Tiefengrammatik as ‘depth grammar’ is somewhat eccentric since this is the antonym of Oberflächengrammatik, making ‘deep grammar’ the more natural choice.

4 Of course, even this sentence could be given a use under certain circumstances.

5 Although an arbitrary definition of the term can always be stipulated (pi §68).

6 Meaning is, for Wittgenstein, defined by use ‘in a large class of cases’ (pi §43).

7 The view to which Wittgenstein (1922) was committed in the Tractatus.

8 This is comparable to Putnam’s (1975) ‘Twin Earth’ thought experiments in which the meaning of a term is shown to vary according to external factors, except that here the relevant factors are distributed in both time and space.

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