The idea of a private language was made famous in philosophy by Ludwig Wittgenstein, who in §243 of his book Philosophical Investigations explained it thus: “The words of this language are to refer to what can be known only to the speaker; to his immediate, private, sensations. So another cannot understand the language.” This is not intended to cover (easily imaginable) cases of recording one’s experiences in a personal code, for such a code, however obscure in fact, could in principle be deciphered. What Wittgenstein had in mind is a language conceived as necessarily comprehensible only to its single originator because the things which define its vocabulary are necessarily inaccessible to others.
Immediately after introducing the idea, Wittgenstein goes on to argue that there cannot be such a language. The importance of drawing philosophers’ attention to a largely unheard-of notion and then arguing that it is unrealizable lies in the fact that an unformulated reliance on the possibility of a private language is arguably essential to mainstream epistemology, philosophy of mind and metaphysics from Descartes to versions of the representational theory of mind which became prominent in late twentieth century cognitive science.
1. Overview: Wittgenstein’s Argument and its Interpretations
Wittgenstein’s main attack on the idea of a private language is contained in §§244–271 of Philosophical Investigations (though the ramifications of the matter are recognizably pursued until §315). These passages, especially those from §256 onwards, are now commonly known as ‘the private language argument’, despite the fact that he brings further considerations to bear on the topic in other places in his writings; and despite the fact that the broader context, of §§243–315, does not contain a singular critique of just one idea, namely, a private language—rather, the passages address many issues, such as privacy, identity, inner/outer relations, sensations as objects, and sensations as justification for sensation talk, amongst others.
Nevertheless, the main argument of §§244–271 is, apparently, readily summarized. The conclusion is that a language in principle unintelligible to anyone but its originating user is impossible. The reason for this is that such a so-called language would, necessarily, be unintelligible to its supposed originator too, for he would be unable to establish meanings for its putative signs.
We should, however, note that Wittgenstein himself never employs the phrase ‘private language argument’. And a few commentators (e.g., Baker 1998, Canfield 2001 pp. 377–9, Stroud 2000 p. 69) have questioned the very existence in the relevant passages of a unified structure properly identifiable as a sustained argument. This suggestion, however, depends for its plausibility on a tendentiously narrow notion of argument—roughly, as a kind of proof, with identifiable premisses and a firm conclusion, rather than the more general sense which would include the exposure of a confusion through a variety of reasoned twists and turns, of qualifications, weighings-up and re-thinkings—and is a reaction against some drastic and artificial reconstructions of the text by earlier writers. Nevertheless, there is a point to be made, and the summary above conceals, as we shall see, a very intricate discussion.
Even among those who accept that there is a reasonably self-contained and straightforward private language argument to be discussed, there has been fundamental and widespread disagreement over its details, its significance and even its intended conclusion, let alone over its soundness. The result is that every reading of the argument (including that which follows) is controversial. Some of this disagreement has arisen because of the notorious difficulty and occasional elusiveness of Wittgenstein’s own text (sometimes augmented by problems of translation). But much derives from the tendency of philosophers to read into the text their own preconceptions without making them explicit and asking themselves whether its author shared them. Some commentators, for instance, supposing it obvious that sensations are private, have interpreted the argument as intended to show they cannot be talked about; some, supposing the argument to be an obvious but unsustainable attempt to wrest special advantage from scepticism about memory, have maintained it to be unsound because it self-defeatingly implies the impossibility of public discourse as well as private; some have assumed it to be a direct attack on the problem of other minds; some have claimed it to commit Wittgenstein to behaviourism or verificationism; some have thought it to imply that language is, of necessity, not merely potentially but actually social (this has come to be called the ‘community view’ of the argument).
The early history of the secondary literature is largely one of disputation over these matters. Yet what these earlier commentators have in common is significant enough to outweigh their differences and make it possible to speak of them as largely sharing an Orthodox understanding of the argument. After the publication in 1982 of Saul Kripke’s definitely unorthodox book, however, in which he suggested that the argument poses a sceptical problem about the whole notion of meaning, public or private, disputation conducted by Orthodox rules of engagement was largely displaced by a debate on the issues arising from Kripke’s interpretation. (However, there is overlap: Kripke himself adheres to the community view of the argument’s implications, with the result that renewed attention has been paid to that issue, dispute over which began in 1954.) Both debates, though, show a tendency to proceed with only the most cursory attention to the original argument which started them off.
This rush to judgment about what is at stake, compounded by a widespread willingness to discuss commentators’ more accessible accounts of the text rather than confront its difficulties directly, has made it hard to recover the original from the accretion of more or less tendentious interpretation which has grown up around it. Such a recovery is one of the tasks attempted in this article. The criterion of success in this task which is employed here is one of coherence: a good account should accommodate all of Wittgenstein’s remarks in §§244–271, their (not necessarily linear) ordering as well as their content, and should make clear how these remarks fit with the context provided by the rest of the book. (One of the problems with many of the commentaries on this matter, especially the earlier ones, is that their writers have quarried the text for individual remarks which have then been re-woven into a set of views said to be Wittgenstein’s but whose relation to the original is tenuous. A striking example of this approach is Norman Malcolm’s famous and influential 1954 review of Philosophical Investigations, which was commonly taken as an accurate representation of Wittgenstein’s own thinking and formed the target of many “refutations”.)
1.1 Recent Developments and Their Consequences
Interpretation of Wittgenstein started to become even more complex at the close of the twentieth century, as commentators began to focus on broad questions of method. In both Tractatus Logico-Philosophicus and Philosophical Investigations there is a tension between some statements that seem to be stating controversial philosophical positions and others that seem to be saying that philosophy ought not to offer controversial theses but only work with what we already know by being competent language users embedded in human circumstances. In the latter book there are passages that seem to support an anti-philosophical position and others that seem to offer interesting new philosophical views in the process of criticizing more traditional philosophical doctrines such as foundationalism and Cartesianism. Along these lines, two overlapping distinctions concerning how to read Philosophical Investigations have arisen: the resolute–substantial distinction, and the Pyrrhonian–non-Pyrrhonian distinction. In general, the resolute and Pyrrhonian readings make Wittgenstein out to be an anti-philosopher, one who is not offering positive philosophical theses to replace false ones; rather, his goal is to show the nonsensical nature of traditional philosophical theorizing. It is this goal that is partly responsible for the unique style of Philosophical Investigations (its dialogical and, at least at times, anti-dogmatic, therapeutic character). On the substantial and non-Pyrrhonian readings, Wittgenstein is not only presenting a method for exposing the errors of traditional philosophers, but also showing how philosophy should rightly be done and thereby offering positive philosophical views, views which must often be inferred or reconstructed from an elusive text.
There is neither a single resolute/Pyrrhonian nor a single substantial/non-Pyrrhonian reading of Wittgenstein. Moreover, there is an important difference between the resolute–substantial and Pyrrhonian–non-Pyrrhonian distinctions. The former distinction arises from a continuing debate on how to read Tractatus Logico-Philosophicus, both on its own and in relation to Philosophical Investigations (see, e.g., Conant 2004 and Mulhall 2007), and is associated with the so-called New Wittgensteinians (see, e.g., Crary and Read 2000). The Pyrrhonian and non-Pyrrhonian discussion is to be found, for example, in Fogelin (1994), Sluga (2004), and Stern (2004, 2007), and concerns the ways in which Wittgenstein might be considered as writing in the tradition of the ancient Pyrrhonian sceptics, who were philosophically sceptical about the very possibility of philosophy (see Fogelin 1994, pp. 3ff and 205ff). These distinctions cut across the distinction between Orthodox and Kripkean non-orthodox readings of the text: both Orthodox and Kripkean non-orthodox interpreters have tended to offer substantial or non-Pyrrhonian readings of Wittgenstein—though the line may not always be clear and some (e.g., Hacker, 1990) move from a resolute/Pyrrhonian to a substantial/non-Pyrrhonian reading without remarking the fact.
Some (Fogelin, Stern, and Mulhall, for example) have come to question whether it makes sense to suppose that either one or the other, resolute/Pyrrhonian or substantial/non-Pyrrhonian, must be the correct way to read Wittgenstein. Fogelin and Stern see the tension in the text of Philosophical Investigations as the expression of a tension, indeed a struggle, within its author, between his wanting to uncover the ‘disguised nonsense’ of philosophical theses and his being tempted and drawn into still other philosophical positions on the nature of language, reference, private experience, and philosophy itself. In what is surely a reference to §133c—which reads: ‘The real discovery is the one that makes me capable of stopping doing philosophy when I want to.—The one that gives philosophy peace, so that it is no longer tormented by questions which bring itself in question’—Wittgenstein is reported by Rush Rhees to have said ‘In my book I say that I am able to leave off with a problem in philosophy when I want to. But that’s a lie; I can’t’ (Rhees, 1984, p. 219 n. 7). According to Stern, the Wittgenstein of the Philosophical Investigations is more Pyrrhonian than not, while understanding all too acutely the attraction of philosophy and the difficulty of giving it up. One’s stance on these matters affects how one reads the private language sections, in particular by raising the question whether Wittgenstein intends to argue that the positive claim of the possibility of a private language is false, or is some kind of nonsense.
1.2 Are Claims Affirming the Possibility of a Private Language False or Nonsense?
If someone were to insist that a private language is possible, one way to argue against him would be by employing the method of reductio ad absurdum: assume that it is true that a private language is possible, show that that assumption leads to certain absurdities or a contradiction, and then conclude that it is actually false that a private language is possible. This is the way in which the argument was typically understood. But this understanding has come into question. In contrast to his earlier commentaries, for example, Gordon Baker has since called into question whether the private language sections should not be read as attempting to show that the notion of a private language is intelligible but false, but rather that it is nonsense masquerading as an important possibility (Baker, 1998).
There is, however, in Wittgenstein’s thinking an inclination to think of contradiction in terms of the disintegration of sense, so that even argument by reductio might be understood not in terms of falsehood. (The appearance of this inclination in Tractatus Logico-Philosophicus, for example, is well mapped by Fogelin [1976, Ch. IV].) And it is characteristic of Wittgenstein to talk of philosophical error in terms of nonsense. In §119 of Philosophical Investigations he wrote, e.g., ‘The results of philosophy are the uncovering of one or another piece of plain nonsense and of bumps that the understanding has got by running its head against the limits of language. These bumps make us see the value of the discovery.’ And in §464: ‘My aim is: to teach you to pass from a piece of disguised nonsense to something that is patent nonsense.’ In the discussion of the possibility of a private language it may well at first seem as though we understand the possibility under consideration. After all we seem to understand the question in §256, ‘Now, what about the language which describes my inner experiences and which only I myself can understand?’ But is Wittgenstein suggesting we only seem to understand this question?
The matter may not be clear. Shortly after the main private language sections, the following remark occurs as part of a dialogue, ‘It comes to this: only of a living human being and what resembles (behaves like) a living human being can one say: it has sensations; it sees; is blind; hears; is deaf; is conscious or unconscious’ (§281). The dialogue continues in §282:
“But in a fairy tale the pot too can see and hear!” (Certainly; but it can also talk.)
“But the fairy tale only invents what is not the case: it does not talk nonsense.”—It is not as simple as that. Is it false or nonsensical to say that a pot talks? Have we a clear picture of the circumstances in which we should say of a pot that it talked? (Even a nonsense-poem is not nonsense in the same way as the babbling of a child.)
Here the question of how the Investigations is to be read intrudes. For example, part of the distinction between what Mulhall calls resolute and substantial readings of Wittgenstein concerns the sense in which Wittgenstein aimed to ‘overcome our attraction to the idea that there is something that we cannot do in philosophy’ (Mulhall, 2007, p. 8; cf. Philosophical Investigations §374). Mulhall claims that that idea goes against the moral of Investigations §500: ‘When a sentence is called senseless, it is not as it were its sense that is senseless. But a combination of words is being excluded from the language, withdrawn from circulation.’ Further, this substantial reading attributes to Wittgenstein an implicit philosophical theory of meaning, ‘of the (now grammatical) conditions of sense—quite as if our everyday abilities to distinguish sense from nonsense require at the very least a philosophical grounding or foundation (perhaps a criterial semantics, or a theory of language-games, or an anthropology of the human life form’ (Mulhall, 2007, p. 9). By contrast, on a resolute reading of Philosophical Investigations, Wittgenstein’s appeal to the notion of a grammatical investigation involves the deployment of ‘our everyday capacity to distinguish sense from nonsense in a philosophical context, and hence as depriving itself of any claim to expertise or authority that exceeds that form of practical ability—an ability that can equally well be laid claim to by any competent speaker, and hence by any philosophical interlocutor’ (ibid., p. 10). Further, the resolute reading is especially firm in rejecting the idea that there is something determinate that we cannot do, the idea that there is something, namely, a private language, that cannot be achieved; there is not a limitation on language. Rather, the idea is simply nonsense, or as Mulhall later puts it (ibid. p. 18): no sense can be given to the idea of a philosophically substantial private language.
Though Mulhall claims that the private language sections can justifiably be read either resolutely or substantially—because ‘each reading can … point to an aspect of the text that it fully acknowledges, and whose proper acknowledgment by the other is at the very least an issue for it, it would seem profitless to insist that one reading is essentially faithful to Wittgenstein’s text and the other intrinsically faithless’ (ibid., p. 20)—it is plain that he thinks the resolute reading is to be preferred. However, we may not need to choose. We might view the private language sections as Wittgenstein’s asking, ‘Do we have a clear picture of the circumstances in which we should say that someone spoke a private language?’ The line of reasoning that follows §243 can be read as various attempts to achieve a clear picture of what it might mean to speak a private language, where the attempts ultimately fail, with the result that what at first sight seemed intelligible (‘a language which describes my inner experiences and which only I myself can understand’) turns out not to be intelligible after all. And in so far as we cannot make intelligible the circumstances in which there could be a private language, we should say that the idea of a private language is nonsense. However, as we saw above, in §282 Wittgenstein indicates that the border between nonsense and falsehood is itself unclear; and moreover, in trying to make sense of the possibility of a private language, we may find, in different parts of the chain of reasoning, suggestions of falsehood as well as of nonsensicality.
2. The Significance of the Issue
The issue’s significance can be seen by considering how the argument is embedded in the structure of Philosophical Investigations. Immediately prior to the introduction of the argument (§§241f), Wittgenstein suggests that the existence of the rules governing the use of language and making communication possible depends on agreement in human behaviour—such as the uniformity in normal human reaction which makes it possible to train most children to look at something by pointing at it. (Unlike cats, which react in a seemingly random variety of ways to pointing.) One function of the private language argument is to show that not only actual languages but the very possibility of language and concept formation depends on the possibility of such agreement.
Another, related, function is to oppose the idea that metaphysical absolutes are within our reach, that we can find at least part of the world as it really is in the sense that any other way of conceiving that part must be wrong (cf. Philosophical Investigations p. 230). Philosophers are especially tempted to suppose that numbers and sensations are examples of such absolutes, self-identifying objects which themselves force upon us the rules for the use of their names. Wittgenstein discusses numbers in earlier sections on rules (185–242). Some of his points have analogues in his discussion of sensations, for there is a common underlying confusion about how the act of meaning determines the future application of a formula or name. In the case of numbers, one temptation is to confuse the mathematical sense of ‘determine’ in which, say, the formula y = 2x determines the numerical value of y for a given value of x (in contrast with y > 2x, which does not) with a causal sense in which a certain training in mathematics determines that normal people will always write the same value for y given both the first formula and a value for x—in contrast with creatures for which such training might produce a variety of outcomes (cf. §189). This confusion produces the illusion that the result of an actual properly conducted calculation is the inevitable outcome of the mathematical determining, as though the formula’s meaning itself were shaping the course of events.
In the case of sensations, the parallel temptation is to suppose that they are self-intimating. Itching, for example, seems like this: one just feels what it is directly; if one then gives the sensation a name, the rules for that name’s subsequent use are already determined by the sensation itself. Wittgenstein tries to show that this impression is illusory, that even itching derives its identity only from a sharable practice of expression, reaction and use of language. If itching were a metaphysical absolute, forcing its identity upon me in the way described, then the possibility of such a shared practice would be irrelevant to the concept of itching: the nature of itching would be revealed to me in a single mental act of naming it (the kind of mental act which Russell called ‘acquaintance’); all subsequent facts concerning the use of the name would be irrelevant to how that name was meant; and the name could be private. The private language argument is intended to show that such subsequent facts could not be irrelevant, that no names could be private, and that the notion of having the true identity of a sensation revealed in a single act of acquaintance is a confusion.
The suggestion that a language could be private in the way described appears most openly in the second of Bertrand Russell’s published lectures ‘The Philosophy of Logical Atomism’, where Russell says:
In a logically perfect language, there will be one word and no more for every simple object, and everything that is not simple will be expressed by a combination of words, by a combination derived, of course, from the words for the simple things that enter in, one word for each simple component. A language of that sort will be completely analytic, and will show at a glance the logical structure of the facts asserted or denied. … A logically perfect language, if it could be constructed, would not only be intolerably prolix, but, as regards its vocabulary, would be very largely private to one speaker. That is to say, all the names that it would use would be private to that speaker and could not enter into the language of another speaker.
… A name, in the narrow logical sense of a word whose meaning is a particular, can only be applied to a particular with which the speaker is acquainted, because you cannot name anything you are not acquainted with.
… One can use ‘this’ as a name to stand for a particular with which one is acquainted at the moment. We say ‘This is white’. … But if you try to apprehend the proposition that I am expressing when I say ‘This is white’, you cannot do it. If you mean this piece of chalk as a physical object, then you are not using a proper name. It is only when you use ‘this’ quite strictly, to stand for an actual object of sense [i.e., a sense-datum], that it is really a proper name. And in that it has a very odd property for a proper name, namely that it seldom means the same thing two moments running and does not mean the same thing to the speaker and to the hearer.
… [I]n order to understand a name for a particular, the only thing necessary is to be acquainted with that particular. When you are acquainted with that particular, you have a full, adequate and complete understanding of the name, and no further information is required.
Although Wittgenstein does not explicitly say so, it is likely that this is the inspiration of his argument: his writing is marked in many places by criticism of Russell, both explicit and otherwise.
But the idea of a private language is more usually hidden: the confusions supposed to belong to it allegedly underlie a range of articulated philosophical notions and theories, without themselves being so articulated. The argument is thus perhaps most profitably read as targeting, not any particular theory, but rather the motivation for considering a range of apparently independent or even competing theories along with their associated tasks, problems and solutions.
For example, a still very common idea, often attributed to John Locke and openly embraced by Jerry Fodor in the nineteen seventies, is that interpersonal spoken communication works by speakers’ translation of their internal mental vocabularies into sounds followed by hearers’ re-translation into their own internal vocabularies. Again, Descartes considered himself able to talk to himself about his experiences while claiming to be justified in saying that he does not know (or not until he has produced a reassuring philosophical argument) anything at all about an external world conceived as something independent of them. And he and others have thought: while I may make mistakes about the external world, I can infallibly avoid error if I confine my judgments to my immediate sensations. (Compare The Principles of Philosophy, I, 9.) Again, many philosophers, including John Stuart Mill, have supposed there to be a problem of other minds, according to which I may reasonably doubt the legitimacy of applying, say, sensation-words to beings other than myself.
In each of these examples, the implication is that the internal vehicle of my musings could in principle be private (as Kenny [1966, p. 369] showed, this vehicle does not have to be a language for the argument to apply to it): for these problems and theories even to make sense, sharability must be irrelevant to meaning and it must be at least conceivable that my knowledge, even my understanding, is necessarily confined to my own case. The implication is of course often denied. The terms of Fodor’s language of thought, for example, are supposed to be able to refer to public objects. But the question is, on what basis does this ability rest? However this question should be answered, Fodor himself was concerned enough about Wittgenstein’s argument to try to show both that it did not apply to his views and—apparently superfluously—that it is not a good argument anyway (Fodor pp. 68–73). The matter is clearer with Descartes (compare Kenny 1966): for his sceptical question to be raised without being immediately self-defeating, he must hold it possible to identify his experiences inwardly—where ‘inwardly’ means without relying on resources supplied by his essential embodiment in a world whose existence is independent of his own mind and accessible to others (e.g., such resources as the concepts acquired in a normal upbringing). The question which accordingly looms large in the private language argument is: How is this identification of one’s experiences to be achieved?
However, it cannot be emphasized too strongly that the significance of the private language argument does not rest on the scholarly detail of whether this or that thinker can be correctly described as committed to the idea. The target is a way of thinking which generates philosophical theories, not the theories themselves.
3. The Private Language Argument Expounded
As already noted, the private language sections of Philosophical Investigations are usually held to begin at §243 (though we shall see that Wittgenstein relies on points made much earlier in the book). The methodological issues canvassed above arise at the outset, in the interpretation of §243’s crucial second paragraph.
On a substantial/non-Pyrrhonian reading, Wittgenstein begins to clarify what kind of philosophically important notion of private language is to be examined, i.e., one that is necessarily private and which refers to one’s immediate private sensations. In the remarks that follow, Wittgenstein argues that the idea of such a private language is nonsensical or incoherent because it is a violation of grammar (i.e., Wittgenstein draws on his substantive views on meaning).
On a resolute/Pyrrhonian reading, it is emphasized that the reader is asked in the first sentence of the second paragraph whether one can actually imagine a language for one’s inner experiences, for private use. Wittgenstein at this point reminds the interlocutor that we already use ordinary language for that. But the interlocutor quickly replies in the last three lines of §243 that what he is asking is whether we can imagine a private language that refers to what only the speaker can know. In the following sections, Wittgenstein examines ‘whether there is a way of meaning the words of the penultimate sentence
There is, however, reason to believe that this assumption is false, for investigation of Wittgenstein’s notions of essential, possible and lifelong Crusoe shows that admission of the first claim does not commit him to the denial of the second. To take the first notion: on Wittgenstein’s view, while chess is essentially a game for two players, this does not exclude the possibility of playing it against oneself provided such solitary games are not regarded as paradigm instances of chess. Similarly, he can claim that language is essentially social, but still allow the possibility of exceptions provided these are peripheral cases. The issue is complex, and its pursuit would lead away from the current article’s purpose of articulating the central text. For a detailed account, the reader is referred to Canfield  (to which this section is indebted, and which also contains a useful bibliography of the debate over the community view), and to Hacker .
The secondary literature on this topic is enormous. The following list is highly selective, and entries are included by meeting at least one of the following criteria: good representative of a standard reading of the argument; influential source, primary or secondary; useful collection of items meeting one or other of the previous two criteria; useful survey; item making recent and significant progress in the understanding and assessment of the argument; source drawn on in the writing of this article; item mentioned in the main text of this article.
Baker, G.P., 1998, ‘The private language argument’, Language & Communication, 18: 325–56.
Baker, G.P. & Hacker, P.M.S., 1990, ‘Malcolm on language and rules’, Philosophy, 65: 167–79.
Boghossian, P.A., 1989, ‘The rule-following considerations’, Mind, 98: 507–49.
Candlish, S., 1997, ‘Wittgensteins Privatsprachenargumentation’, in Eike von Savigny (ed.), Wittgensteins Philosophische Untersuchungen, Berlin: Akademie Verlag: 143–65.
Canfield, J.V. (ed.), 1986, The Philosophy of Wittgenstein, Volume 9: The Private Language Argument, New York: Garland.
––– (ed.), 1986, The Philosophy of Wittgenstein (Volume 10: Logical Necessity and Rules), New York: Garland.
–––, 1996, ‘The community view’, The Philosophical Review, 105: 469–88.
–––, 2001, ‘Private language: the diary case’ Australasian Journal of Philosophy, 79: 377–94.
Conant, J., 2004, ‘Why worry about the Tractatus?’, in B. Stocker (ed.), Post-Analytic Tractatus, Aldershot: Ashgate: 167–92.
Cook, J.W., 1969, ‘Human beings’, in P. Winch, (ed.), Studies in the Philosophy of Wittgenstein, London: Routledge & Kegan Paul.
Crary, A. & Read, R. (eds.), 2000, The New Wittgenstein, London and New York: Routledge.
Fodor, J., 1975, The Language of Thought, New York: Crowell.
Fogelin, R.J., 1976, Wittgenstein, London: Routledge, Ch. XIII.
–––, 1994, Pyrrhonian Reflections on Knowledge and Justification, New York and Oxford: Oxford University Press.
Hacker, P.M.S., 1990, Wittgenstein: Meaning and Mind, Volume 3 of an Analytical Commentary on the Philosophical Investigations, Oxford: Blackwell.
–––, 2010, ‘Robinson Crusoe Sails Again: The Interpretative Relevance of Wittgenstein’s Nachlass’, in N. Venturhina (ed.), Wittgenstein After His Nachlass, Basingstoke and New York: Palgrave Macmillan.
Jones, O.R. (ed.), 1971, The Private Language Argument, London: Macmillan.
Kenny, A., 1966, ‘Cartesian privacy’, in G. Pitcher (ed.), Wittgenstein: The Philosophical Investigations, London: Macmillan, 1968.
–––, 1973, Wittgenstein, London: Allen Lane, Ch. 10.
Kripke, S., 1982, Wittgenstein on Rules and Private Language, Oxford: Blackwell.
Malcolm, N., 1954, ‘Wittgenstein’s Philosophical Investigations’, The Philosophical Review, 63: 530–59.
–––, 1989, ‘Wittgenstein on language and rules’, Philosophy, 64: 5–28.
McDowell, J., 1989, ‘One Strand in the Private Language Argument’, Grazer Philosophische Studien, 33/34: 285–303.
Mulhall, S., 2007, Wittgenstein’s Private Language: Grammar, Nonsense, and Imagination in Philosophical Investigations, §§ 243–315, Oxford: Clarendon Press.
Nielsen, K.S., 2008, The Evolution of the Private Language Argument, Aldershot: Ashgate.
Pears, D., 1988, The False Prison (Volume Two), Oxford: Clarendon Press, Chs. 13–15.
Rhees, R. (ed.), 1984, Recollections of Wittgenstein, revised edition, New York: Oxford University Press. Originally published as Ludwig Wittgenstein: Personal Recollections, Oxford: Blackwell, 1981.
Russell, B., 1918, ‘The philosophy of logical atomism’, in The Collected Papers of Bertrand Russell (Volume 8: The Philosophy of Logical Atomism and Other Essays 1914–19), London: George Allen and Unwin, 1986.
Sluga, H., 2004, ‘Wittgenstein and Pyrrhonism’, in W. Sinnott-Armstrong (ed.), Pyrrhonian Skepticism, Oxford and New York: Oxford University Press, 99–117.
Stern, D.G., 2004, Wittgenstein’s Philosophical Investigations: an introduction, Cambridge: Cambridge University Press.
–––, 2007, ‘The uses of Wittgenstein’s beetle: Philosophical Investigations §293 and its interpreters’, in G. Kahane, E., Kanterian, and O. Kuusela (eds.), Wittgenstein and his Interpreters: Essays in Memory of Gordon Baker, Malden: Blackwell: 248–68.
–––, 2010, ‘Another strand in the private language argument’, in A. Ahmed (ed.), Wittgenstein’s Philosophical Investigations: A Critical Guide, Cambridge and New York: Cambridge University Press, 178–96.
–––., 2011, ‘Private language’, in O. Kuusela and M. McGinn (eds.), The Oxford Handbook of Wittgenstein, Oxford: Oxford University Press: 333–50.
Stroud, B., 2000, Meaning, Understanding, and Practice, Oxford: Oxford University Press, Essays 5, 6 and 13.
Tang, H., 2014, ‘“It is not a something, but not a nothing either” – McDowell on Wittgenstein’, Synthese, 191: 557–67.
Winch, P., 1983, ‘Facts and superfacts’, The Philosophical Quarterly, 33: 398–404; revised and reprinted in P. Winch, Trying to Make Sense, Oxford: Blackwell, 1987, 54–63.
Wittgenstein, L., 1953, Philosophical Investigations, translated by G. E. M. Anscombe, Oxford: Blackwell, 3rd edition, 1967.
–––, 1934–6, ‘Notes for lectures on “private experience” and “sense-data”’, The Philosophical Review, 77 (1968): 275–320. (Also included in Jones 1971.)