Book Review: Philosophical Investigations by Wittgenstein

post by Chris_Leong · 2021-10-12T20:14:59.043Z · LW · GW · 9 comments


  Philosophical Investigations
    model of language
    and Training
    as Use
    as Anti-Philosopher
    Private Language Argument
    to Linguistic Freedom
    and Maths
    to Conceptual Engineering
  Should you read this book?

Ludwig Wittgenstein is often considered one of the greatest philosophers of the 20th century and is certainly one of its most fascinating figures. Here's some facts to illustrate:

I enjoyed reading this book as Wittgenstein is eminently quotable and he writes with crystal clear language. However, the book is incredibly challenging due to the lack of structure, his preference to be implicit rather than explicit and the challenge of understanding how any particular sentence fits into to the overall picture.

Here are some reasons why I consider this book of relevance to this community:

Please note that despite my best attempt to separate out what Wittgenstein was arguing and how I interpreted him, there will inevitably be areas where I end up reinterpreting without meaning to do so. I especially want to emphasise that the relevance sections I've added are just intended to provide one interpretation of how these ideas are relevant.


Given that a large part of the Philosophical Investigations criticises the positions he defended in Tractatus, we'll begin with a brief overview of earlier book. He even notes in the preface of the latter work that it will be hard to understand The Investigations except by contrast with the Tractatus. I haven't read Tractatus, the following is based on secondary material. 

Wittgenstein attempts to give an account of language - in particular, of what can and can't be said where said effectively means said with any real precision. He is trying to persuade us that there are certain things that we can't speak precisely about, and that we should therefore stop trying to philosophise about these ("Whereof one cannot speak, thereof one must be silent").

The account he provides of truth is known as the Picture Theory of Meaning. This asserts that a proposition is true when the picture representing that proposition corresponds to reality. Pictures consist of elements standing in relations with the elements representing real-world objects which stand in a particular state of affairs. In particular, Wittgenstein claims that we can't sensibly speak of things that can't be represented by these kinds of pictures.

This is not to imply that everything that can't be spoken of is unimportant or non-existent. In fact, he even suggests that these might be the most important things of all:

There are, indeed, things that cannot be put into words. They make themselves manifest. They are what is mystical.

Picture theory is normally taken to be assuming a Correspondence Theory of Truth where Correspondence Theory claims that a proposition is true when it corresponds in some way to how the external world is. One way to clarify the meaning of Correspondence Theory is to consider the most prominent alternative - Coherentism. Coherentism claims that insofar as there is such a thing truth to which we can aspire, it consists of ensuring that our propositions are coherent, rather than trying to make them correspond to some kind of external reality.

Wittgenstein's Picture Theory adopts a kind of logical atomism which Wikipedia describes as follows:

The world consists of ultimate logical "facts" (or "atoms") that cannot be broken down any further, each of which can be understood independently of other facts.

The Stanford Encylopedia of Philosophy contains more technical description.

These atomic propositions assert the existence of atomic states of affairs which are combinations of simple objects. Wittgenstein doesn't provide much clarity about what these simple objects or states of affair actually. This probably seems like a gaping hole to my readers.

However, A. C. Grayling suggests that having provided the general framework, Wittgenstein might have seen what was left as mere details to be filled in by others. For example, although we might have once been tempted to use atoms as simple objects, these days it would seem that quantum wavefunctions would be a better candidate. Arguably scientists are better positioned than philosophers to fill in the gap by drawing on the latest scientific theories.

Perhaps the biggest flaw of this account is that Picture Theory, as Wittgenstein has characterised it, cannot represent itself. This paradox is noted in the metaphor known as Wittgenstein's Ladder:

My propositions serve as elucidations in the following way: anyone who understands me eventually recognizes them as nonsensical, when he has used them—as steps—to climb beyond them. (He must, so to speak, throw away the ladder after he has climbed up it.). He must transcend these propositions, and then he will see the world aright

The standard reading of this is to take him as having utilised nonsense to demonstrate an ineffable truth that nevertheless remains after the nonsense of the surface-level statements has been exposed. Alternatively: the sentences are there as something to be worked through, rather than as literal assertions.

While this is far from a perfect analogy, the Sokal Hoax involved Alan Sokal submitting nonsense to a journal of cultural studies in order to critique postmodernism. For many people, this constituted an effective critique of postmodernism, despite the fact that he didn't address the issue head on. The submission being utter nonsense and everyone eventually knowing this, didn't prevent it from being persuasive.

(In contrast, the resolute reading asserts that when Wittgenstein asserts that his propositions are nonsense, he means precisely that. That is, that Tracatus is just plain nonsense, rather than some kind of elevated nonsense designed to reveal deep truths. And that end result is not some ineffable truth, but a realisation that Wittgenstein had embarked upon a fundamentally misguided project).

Tractatus isn't the focus of this review, so I'll stop here. However, I do want to note that I have posited my own solution [LW · GW] to the flaw that is picture theory's inability to picture itself.

Philosophical Investigations

Augustine model of language

The Philosophical Investigations starts with a passage from Augustine:

"When they (my elders) named some object, and accordingly moved towards something, I saw this and I grasped that the thing was called by the sound they uttered when they meant to point it out. Their intention was shewn by their bodily movements, as it were the natural language of all peoples: the expression of the face, the play of the eyes, the movement of other parts of the body, and the tone of voice which expresses our state of mind in seeking, having, rejecting, or avoiding something. Thus, as I heard words repeatedly used in their proper places in various sentences, I gradually learnt to understand what objects they signified; and after I had trained my mouth to form these signs, I used them to express my own desires."

 Wittgenstein summarises as providing a picture of language as follows:

The individual words in language name objects—sentences are combinations of such names. In this picture of language we find the roots of the following idea: Every word has a meaning.

Wittgenstein's Picture Theory adopted this kind of approach in that elementary propositions make claims about the relations of elementary objects. Wittgenstein is now explicitly rejecting this theory of language with his first critique being that Augustine doesn't "speak of their being any difference between kinds of word", explaining:

If you describe the learning of language in this way you are, I believe, thinking primarily of nouns like "table", "chair", "bread", and of people's names, and only secondarily of the names of certain actions and properties; and of the remaining kinds of word as something that will take care of itself.

Wittgenstein later suggest that we are fooled into believing words function in roughly the same manner by their "uniform appearance". He uses the analogy of a toolbox, where even though we might class all the contents as tools, the actual tools might be completely unalike. Another image he uses is that of handles on a locomotive which might all like identical, but actually move in quite different ways depending on what they control.

He writes:

When we say: "Every word in language signifies something" we have so far said nothing whatever; unless we have explained exactly what distinction we wish to make.

Wittgenstein introduces the term "Ostensive Teaching of Words" to describe teaching by saying a word whilst simultaneously pointing or otherwise directing the attention of the learner to the relevant object.

Wittgenstein criticises the claim that we learn language through ostensive teaching on the basis that it is only capable of teaching us to associate objects with words and that we need training in order to learn how we're actually supposed to respond to words. For example, imagine a parent shows a child picture of someone striking another person and says the word "punch". If the child responds by punching the parent because they believe that's what they are supposed to do, the parent may very well respond with a timeout or a spanking to teach the child that they performed an unwanted action. Even if we say that the naive child understood the word "punch", its clear that they didn't understand the meaning of the utterance in that context.

Another criticism he makes is that it is very difficult to teach words like "there" and "this" ostensively. Perhaps you could point to an object then take your other hand and alternate between pointing at your first finger and the object. However, this is kind of awkward and no-one does this.

Relevance: The Augustine model of language and obstensive teaching incline us towards a model where the meaning of words is represented by propositions as propositions focus on objects as the bearers of properties or as the subjects or agents of actions. Wittgenstein undermines these models of teaching/language in favour of the importance of training in learning and a model of language as use.

Explanation and Training

Wittgenstein doesn't believe that explanation is a sufficient tool for teaching people language. After all, we cannot understand an explanation unless we already understand its terms and how to interpret it. That is, explanation always seems to stand in need of further explanation:

Does the sign-post leave no doubt open about the way I have to go? ... But where is it said which way I am to follow it; whether in the direction of its ringer or (e.g.) in the opposite one?—And if there were, not a single sign-post, but a chain of adjacent ones or of chalk marks on the ground—is there only one way of interpreting them?

At this point we might wonder how we are able to talk at all. Wittgenstein's solution is to deny the need to explain everything:

Explanations come to an end somewhere


As though an explanation as it were hung in the air unless supported by another one.

At some level, we just do things because we've been trained to, not because it was explained to us. For example, a child might learn to say water whenever they are thirsty because this results in them recieving the water, leading their brain to send pleasure signals. This is probably instinctual at first and it is likely only later that we developed consciousness awareness of what it is that we are doing.

Relevance: If we learn language via training, then this will naturally incline us more towards his theory of language as use

His views on epistemology follow the exact same pattern: we can't have a reason for everything, so at some level, we just do things.


Wittgenstein considers an example where a builder shouts "Slab!" to get an assistant to bring them a slab. We might be tempted to say that "Slab!" is a shortening of "Get me a slab", but Wittgenstein points out that it makes equally as much sense to say "Get me a slab" is a lengthening of "Slab!".

He acknowledges that it might make sense to say that "Slab!" means "Bring me a slab" in contrast to statements such as "Get him a slab" or "Find a slab!", but he rejects going so far as to claim that's the definition of "Slab!" is something along these lines. Part of his argument is to deny that when we say "Slab!" we necessarily form in our minds a full expression like "Bring me a slab". Indeed, if we make extensive use of this expression, I would expect "Slab!" to become a single unit of thought.

For Wittgenstein this isn't just a curious fact about what goes through our heads when we invoke expressions like "Slab!". Rather, it is a point against any theory that claims that such expressions really represent something else, including the theory that the something else is a proposition.

Here's another example. Suppose someone says, "Leave!". Picture theory might reinterpret this as a logical proposition identifying the worlds where I leave. But surely, I'm not meant to only picture leaving, but to actually leave. An alternative characterisation of picture theory would interpret this by producing a picture of my brain where I have some kind of desire to leave. But this doesn't fully capture the meaning of "Leave!" as people can say things even when they don't desire them. Perhaps I really want you to stay, but I know it would be best for you to leave. Or perhaps, I don't know what I want, and I told you to leave in response to being overwhelmed.

Later Wittgenstein writes that people who are confused about language will be inclined to ask:

"What is a question?" —Is it the statement that I do not know such-and-such, or the statement that I wish the other person would tell me . . . .? Or is it the description of my mental state of uncertainty?"

All three examples appear to lack a straightforward translation into propositions; at least without being reductive. Instead, these words seem to represent actions and they are better understood as an attempt to achieve a result.

Relevance: These considerations further lay the ground for Wittgenstein's theory of language as use by demonstraing the limit of modelling language as propositions.

Language as Use

Reframing all language in terms of logical propositions is particularly tempting to those with rationalist inclinations, but we've already seen in the last section that it isn't as straightforward as we might imagine. 

We noted that if someone says "Leave!" they don't want you to just form a picture of yourself leaving in your head, but to actually actually leave. That is, we can conceive of an agent that has a mere propositional understanding in that they can form a picture of the desired action, but without knowing what they are supposed to do with it. For example, are they supposed to leave, to pretend to leave, say they are thinking of leaving or to do the opposite and not leave?

Compare with the following quote from The Investigations:

Imagine a picture representing a boxer in a particular stance. Now, this picture can be used to tell someone how he should stand, should hold himself; or how he should not hold himself; or how a particular man did stand in such-and-such a place; and so on

Perhaps the image of the boxer seems a little silly, but I was trying to illustrate a deeper point. Wittgenstein asks whether this kind of propositional understanding is the meaning of expressions and for him it is clear that it is not. While being able to bring to mind appropriate images undoubtedly assists in achieving our purposes, it seems that we use words because we want to actually achieve something in the world. Further, this example illustrates one reason why we might want to follow Wittgenstein and conceive of learning language as training, rather than ostensive teaching.

It's worth noting that Wittgenstein doesn't ideologically insist that language is use in all cases, just that it is use in most cases. We haven't covered the concept of language-games yet, but I would argue that the natural development of Wittgenstein's ideas would be to allow meaning as use to play a larger or a smaller role depending on the particular language-game in question.

I think Wittgenstein wants to analyse meaning at the level of linguistic act rather than individual words, although I'm not confident in this interpretation.

Relevance: Rationalists have a tendency to insist on using words rather literally. This certainly has advantages - sticking to this rule reduces our ability to frame situations in accordance with our biases and can help train precise thought. On the other hand, if we accept Wittgenstein's argument that language is primarily about use there's a sense in which this would be attempting to use language in a way contrary to its nature. This isn't an essentialist claim - it's simply a claim that it's often easier to go with the flow such as moving things downhill rather than uphill or driving the "right" way down a street. So this would be an argument for using language in a more "normie" way.

Additionally, I see language as use as broadly analogous to the economic concept of revealed preferences. When economists talk about revealed preferences, on the most part they aren't actually claiming that doing something necessarily means that there's a sense in which we prefer it, rather that given our tendency to be unreflective and to deceive ourselves and others, in many cases it is better to look at what we do rather than what we say. Language as use seems to be making a similar move in terms of language.

Arguably, if we attempt to understand language by asking people what words mean people will just concoct some kind of hand-wavey explaination would provide a misleading picture of how the word is actually used. We can see this by noting the difficulty of defining words we use all the time. Given this, the language as use approach seems highly fruitful.

Family Resemblances

Wittgenstein uses this term to describe phenomena that "have no
one thing in common... but that they are related to one another in many different ways". For example, we can imagine all members of a family appearing similar despite there being no one single feature that every member has. To be clear, most of the members of the family might have the same eyes, same hair and same facial structure, but for each such feature there would be at least one person who is the exception.

This broadly corresponds to Elizer's Yudkowsky's description of The Cluster Structure of Thingspace [LW · GW]. Eliezer's definition is more amenable to mathematical formalisation, but there are slight differences between the kinds of sets that are defined by having N out of M attributes and those sets that are formed via some kind of distance metric.

If you are worried that the concept of family resemblances is kind of vague, I would suggest that Wittgenstein has a strong defence for not having specified them more precisely. This defence is that family resemblances are themselves family resemblances, which by their nature are not very amenable to precise definition.

Note that Wittgenstein doesn't claim concepts are always family resemblances, for example, he acknowledges that we can provide "rigid limits" for what falls within a particular class. Instead, the point is that often our regular use of language often does not draw boundaries nearly so cleanly.

Even though both Wittgenstein and rationalists embrace similar ideas here, there is a stark difference in behaviour. Rationalists understand that there is often no set of necessary and sufficient conditions that captures precisely what we mean by a word, yet often adopt such definitions anyway due to pragmatism. On the other hand Wittgenstein responds by mostly eschewing explicit definitions and instead leans towards listing examples (See Intension and Extension in Logic and Semantics).

Relevance: Understanding this concept helps avoid pointless linguistic disputes or falling into dysfunctional versions of conceptual analysis [LW · GW].


Language-games are another one of the most famous concepts that Wittgenstein introduced. Since Wittgenstein considers these to be a family resemblance, he doesn't provide an explicit definition, but instead explains by way of examples:

Review the multiplicity of language-games in the following examples, and in others:

  • Giving orders, and obeying them
  • Describing the appearance of an object, or giving its measurements
  • Constructing an object from a description (a drawing)
  • Reporting an event
  • Speculating about an event
  • Forming and testing a hypothesis
  • Presenting the results of an experiment in tables and diagrams
  • Making up a story; and reading it
  • Play-acting
  • Singing catches
  • Guessing riddles
  • Making a joke; telling it
  • Solving a problem in practical arithmetic
  • Translating from one language into another
  • Asking, thanking, cursing, greeting, praying.

Roughly, I interpret language-games as referring to a particular activity or purpose for which language is used and which follows its own distinctive rules. I consider it valid to consider a use of language part of a number of different language-games depending on how we want to frame it.

The Stanford Encyclopedia of Philosophy describes language-games as follows:

Language-games are, first, a part of a broader context termed by Wittgenstein a form of life. Secondly, the concept of language-games points at the rule-governed character of language. This does not entail strict and definite systems of rules for each and every language-game, but points to the conventional nature of this sort of human activity. Still, just as we cannot give a final, essential definition of ‘game’, so we cannot find “what is common to all these activities and what makes them into language or parts of language”

Regarding the first point, Wittgenstein seems to believe that it is impossible to understand a language-game outside of the context in which it is practised - "If a lion could speak, we could not understand him".

Consider the biblical injunction to "turn the other cheek". This is typically understood as suggesting that the most virtuous path is not fighting back against (perhaps figurative) violence, but instead allowing further injury.

On the other hand, Walter Wink has interpreted this as suggesting nonviolent resistance to attempts by their social superiors to humiliate them. One way to humilate someone was to give them with a backhands slap to their cheek. However, by turning their face, it would be impossible for them to be backhand slapped with their right hand as their nose would be blocking their cheek. Cultural tradition forbade the use of the left hand except for unclean tasks and a punch would be seen as a sign of equality.

Regardless of whether of not this theory turns out to be correct, it demonstrates potentially how difficult it can be to understand a statement outside of its cultural context; the seeming impossibility of severing certain expressions from the form of life.

When he says that language-games having rules, he doesn't mean everything is precisely specified - indeed that would be contrary to his concept of family resemblances. Further he allows these rules cannot have exceptions; these exceptions often need rules in order to subvert them. His point seems to be that without rules language wouldn't be usable for communiation.

Another aspect of the metaphor of language-games that resonates with me is the idea that we can also create new language-games. When a new situations arises, a new language-game can be created to handle it. This turns language into a realm of creativity.

Relevance: We've covered a lot of different aspects of language-games, but the most important aspect of it for me is as an exhortation to take seriously the diversity of different ways that language can be used and to be very skeptical about any attempts at universal statements.

For example:

Wittgenstein as Anti-Philosopher

In both the the Tractatus and Investigations, Wittgenstein was highly critical of philosophy. In Tractaus, his critique was that philosophers attempted to debate or argue for theses that didn't correspond to a picture of the world. In Philosophical Investigations, Wittgenstein's critique is words are used outside of the language-games in which they make sense - or that "language goes on holiday".

The results is abstract questions which aren't grounded in anything and which don't have any consequences outside of philosophical spectulation. Wittgenstein uses the following as examples of words abused by philosophy: "knowledge", "being", "object", "I", "proposition", "name".

For Wittgenstein, the consequence is that the vast majority of philosophical questions aren't real questions, but simply nonsense. These questions aren't resolved (ie. answered), but dissolved. He sees his task as "to show the fly the way out of the fly bottle"; this it to help philosophers escape problems that they created for themselves.

As an example, many philosophers have deeply pondered the question, "What is Being?". For Wittgenstein, this question wouldn't make sense. Wittgenstein suggests that what we mean by Being is "existence and non-existence of connexions between elements". For example, if we say that there happens to be a complete set of playing cards on my desk, I mean that there are elements representing one of each kind of card which are connected by all being located next to each other. And if I say that there happens to be a suitable candiate I may mean that there's a single person who has the skill, determinination and experience to handle the role; that is that these attributes are connected by all being contained in the one person.

For Wittgenstein it doesn't really make sense to talk about individual elements existing in any non-trivial sense. He writes: "If this thing did not exist, we could not use it in our language-game". That is, saying that a simple element exists says nothing beyond the fact that this element is part of our language-game. In his mind, asking what it means for a simple element to exist is confused because the notion of existence doesn't have any non-trivial meaning outside of checking whether there is a thing for which the claimed connections hold.

This is further clarified by the following analogy: Wittgenstein suggests that it doesn't really make sense to say that the "standard meter in Paris" is either one meter long or not. The former is a tauntology so it doesn't really say anything of any significance and the later is false.

I'm not completely convinced by charactersation of Being as necessarily concerning connections, but I still think he has a point. When we ask questions like, "What is Being?" we seem to be using this word differently from how we use it everyday life.

For example, if we ask "What does it mean for an animal to be a orangutan?" we probably don't actually care about whether the orangutan is ultimately built up from atoms or quantum wave-functions as opposed to wanting to know how to differentiate it from a gorilla.

Here the language-game consists of trying to differentiate one kind of object from another. And if we try to extend this to differentiate objects that are from objects aren't, it's unclear whether this makes sense, as perhaps there is nothing to compare to. Now, we could try extending the definition from another language-game, but we shouldn't be surprised if we run into the same issue.

Relevance: The general lesson I take from this is to be very careful about trying to use a term outside of the language-game or games that it originates from. Ignore this and our terms risk becoming ungrounded.

Take for example the Sleeping Beauty Problem. This has led to endless debate between the thirders and halvers, but perhaps the issue is that probability is a concept defined for situations where an event can only ever be counted exactly once. Once we leave that region of problem-space it's hardly surprising that the concept of probability starts to come apart. Merely asking, "What is probability?" in the abstract isn't very helpful. Instead we have to pay attention to the language-games that people might want to play in these unusual situations.


Wittgenstein's concept of knowledge is deeply bound up with his concept of language -. Wittgenstein thinks it was a mistake for philosophy to attempt to produce absolute knowledge and that we should only try to produce certainty in terms of what we mean by certainty within our ordinary, everyday language-games.

I can be as certain of someone else's sensations as of any fact. But this does not make the propositions "He is much depressed", "25 x 25 = 625" and "I am sixty years old" into similar instruments. The explanation suggests itself that the certainty is of a different kind"

For Wittgenstein, these are different language-games with different notions of certainty. Different language-games include different methods of either proving or attempting to disprove claims; and claims that pass muster according to these standards are classed as "certain". We might complain that this isn't true certainty as these methods will only reveal the truth under certain assumptions. Wittgenstein's addresses these kinds of doubts when he writes "what we do in our language-game always tests on a tacit presupposition" and "doubting has an end". In other words, this is the best that we can do and seeking absolute certainty like Decartes is foolishness only philosophers engage in.

Wittgenstein goes further and questions whether we really doubt:

But that is not to say that we are in doubt because it is possible for us to imagine a doubt. I can easily imagine someone always doubting before he opened his front door whether an abyss did not yawn behind it, and making sure about it before he went through the door (and he might on some occasion prove to be right)—but that does not make me doubt in the same case

And also whether we can doubt:

But, if you are certain, isn't it that you are shutting your eyes in face of doubt?"—They are shut.


If I see someone writhing in pain with evident cause I do not think: all the same, his feelings are hidden from me

In other words, let's be honest here and not pretend that we doubt things that we don't. Let's accept that there are things that we can't help to believe.

Elsewhere he writes: "What has to be accepted, the given, is—so one could say—forms of life." We can compare this to David Hume's injection to, "be a philosopher; but, amidst all your philosophy, be still a man.” Hume was a famous skeptic who doubted everything from causation to induction. Nonetheless, there was there was David Hume the philosopher and David Hume the billard player. When it was time to play billards, he simply put aside his skepticism that we had any reason to believe that the balls would move the same way that they had in the past. Wittgenstein also emphasised being human, however for him the only reason to be a philosopher is to avoid being fooled by philosophy.

We can also interpret Wittgenstein as making a similar move to Decartes' "I think therefore I am". Any question or statement can be seen as presupposing the existence of the language-game in which it makes sense. So perhaps being too skeptical ends up being self-defeating?

One of his key epistemological claims is that it only makes sense to talk about knowledge when there is some method of falsification or verification. For Wittgenstein, knowledge refers to beliefs that have passed some kind of test, with the appropriate kind of test depending on the language-game the belief comes from. If there is no test that we can apply, then we can't play any language-games related to knowledge, at least in any non-trivial sense. He uses this argument to try to demonstrate that we can't have knowledge of private sensations.

Wittgenstein presents these methods of falsification or verification as being intersubjective rather than objective. That is, the important element is that other people should be able to tell whether or not we are playing the language-game correctly. Without this ability, we wouldn't be able to inculcate people in this language-game.

My main objection to this definition of knowledge is that it carves the joints of the world in a strange way. The existence of some method of verification seems like a somewhat arbitrary criterion as it's not clear that we should put more belief in claims that are unlikely in our prior that have passed some weak level of verification vs. claims that seem extremely likely in our prior, but without any method of verification beyond it appearing as such. Perhaps Wittgenstein could respond that his notion of knowledge isn't supposed to always result in claims designated as knowledge having more certainty than those not so designated. This could be reasonable, but it would significantly lower the stakes of being classed as knowledge or not.

Relevance: Pragmatically, it makes a lot of sense to utilise different definitions of what does or doesn't count as knowledge depending on the use case and the level of certainty required. Naturally, these vary by language-game. On the other hand, if we adopt such a pragmatic definition, we need to be aware of the inconsistencies this introduces for what counts as knowledge.

His claim that we don't doubt certain things is a little black and white for me, but I think he is right to criticise the broadly Cartesian model where we doubt everything and refuse to adopt any belief unless it is proven (I would be surprised if this was an accurate model of Decartes' epistemology, as I understood him as merely proposing it as a useful thought experiment).

Not only does is it unable to get us anywhere (we can't get anything from nothing), it fails to acknowledge that there are limitations to how much we can doubt. Yet this model is incredibly tempting because you might think that we believe has no bearing on what we ought to believe.

However, Frank Ramsey demonstrates how an awareness of this limitations can aid our understanding of epistemology when he writes:

We are all convinced by inductive arguments and our conviction is reasonable because the world is so constituted that inductive arguments lead on the whole to true opinions. We are not, therefore, able to help trusting induction, nor if we could help it do we see any reason why we should.

Engaging with our inability to hold other beliefs makes his argument stronger. And this single counter-example is sufficient by itself to demonstrate that a great deal is lost by never straying outside of the Cartesian model.


Throughout the book, Wittgenstein seems somewhat ambivalent on the existence of external reality. While reading this book, I spent a lot of time struggling to identify his position. I think a good entry point is to consider his position on internal feelings:

The thing in the box has no place in the language-game at all; not even as a something: for the box might even be empty.—No, one can 'divide through' by the thing in the box; it cancels out, whatever it is.

That is, for the purpose of understanding language, it doesn't really matter whether there is anything outside of the language-game. He's not saying that there is nothing outside of it - just that it is irrelevant for the language game. This is not the same as claiming that things outside the language-game are unimportant. In our summary of Tracatus, we already observed that he implied that these might be the most important things of all.

There are, indeed, things that cannot be put into words. They make themselves manifest. They are what is mystical.

On the other, this seems like it might be in tension with his suggestion that disputes between "Idealists, Sophists and Realists" are merely linguistic. The way I understand this is that all three may prefer to use different language in a way that doesn't really affect the language-games we play. That is, a realist might say "Bananas are very satisfying", an idealist my say, "The perception of eating a banana is accompanied by the perception of satisfaction" and the Sophist "My perception of eating a banana is satisfying for me".

Relevance: I also think it's quite reasonable to allow that there might be things that we can't know or observe that would nonetheless be important. (I've argued as such in The Universe Doesn't Have to Play Nice [LW · GW]). Unlike Wittgenstein I'd take this as supporting the notion that the differences between idealism and realism are significant. At the same time, I have sometimes observed people defend a philosophical position by policing grammar. For example, I've seen people who seem to be allergic to any mention of "objective reality", yet make no objection as long as you avoid the certain keywords.

Suppose I ask about how to grow coconuts. Someone who's an idealist may assert that there's no such thing as coconuts, only the perception of coconuts. Even if I consider this a plausible metaphysical theory, I'm going to get annoyed at the person for not answering my question. In this case, as far as I am concerned, the possibility of an external reality is irrelevant. It is a nothing that just cancels out.

Internal Experiences

Just as Wittgenstein tends to be somewhat ambivalent about the existence of the external world, he is tends to be ambivalent about the existence of interal experiences.

Nonetheless, in response to a demand to admit that there is a difference between "pain-behaviour accompanied by pain and pain-behaviour without any pain" he writes:

Admit it? What greater difference could there be?

To the claim that an inner process must take place:

What gives the impression that we want to deny anything?

Again, his position seems to be that the possible existence of inner processes has no impact on how the relevant language-games work.

Wittgestein famously considers the possibility that "only I can know whether I am really in pain" declaring that "in one way this is wrong and in another way it is nonsense". He argues that in the regular, everyday use of the term "know" other can know that we are in pain from how we are acting. And, he argues that on the contrary, if we take pain to be an internal experience, we can't know that we're in pain as there wouldn't be any criteria to distinguish between thinking and knowing.

He boosts these arguments by reminding us of the inherent slipperness of memory. Even if I think my experience of smelling lavander matches when I smelled it in the past, I might be misremembering. Further, I don't really have any criterion about whether two experiences match apart from the fact that they appear this way to me.

When reading The Investigations, I often struggled to try to figure out why he didn't consider himself a behaviourist. In response to, "Are you not really a behaviourist in disguise? Aren't you at bottom really saying that everything except human behaviour is fiction", he responds, "If I do speak of a fiction, then it is of a grammatical fiction"

My interpretation is that rather than claiming internal sensations are a myth, he is claiming the talk of internal sensations is a myth, in terms of being a surface-level appearence. For example, he suggests that "There has just taken place in me the mental process of remembering" can be understood as just another way of saying, "I have just remembered". That is, he tends towards interpreting talk about internal processes figuratively, but whilst  denying literal interpretations which involve "the yet uncomprehended process in the yet unexplored medium".

He makes a number of arguments for inner experiences not being a necessary component for a use of  language to have a particular meaning or for us to have a particular understanding. One is that if he introspects, sometimes these experiences are there, but sometimes they are not. Another is that if we learned that someone had the same feeling when using "if" and "but" we might think it unusual, but we wouldn't claim they didn't understand how to use the words.

I see these as reasonable objections to attempts to ground meaning in emotions, however he seems to have been assuming that these processes must be conscious, which is definitely questionable. I often felt that he was adopting positions that would be much less tenable today given the advance of neuroscience. However, he addresses this kind of argument by imagining that his blood pressure rises whenever he has a particular sensation:

So I shall be able to say that my blood-pressure is rising without using any apparatus. This is a useful result. And now it seems quite indifferent whether I have recognized the sensation right or not.

So maybe Wittgenstein would argue that neuroscience expands the scope of language insofar as language is understood as an intersubjective, error-correcting system of communication and co-ordination.

Relevance: Even though "He is in pain" nominally claims that someone is undergoing a particular experience, that need to be the intent. Someone may not, for example, believe that humans are nothing but machines and disbelieve the notion of subjective experience, yet they may make that statement so that the person is administered pain-killers so that they shut up. Alternatively, we can imagine someone who isn't really sure about whether or not qualia exists, but who figures that they may as well proceed on the basis that there is qualia because that is the most natural thing to do.

As another example, suppose someone says, "I'm thirsty". Nominally, it asserts that the are experiencing a sensation (that of thirst). But perhaps they just want you to pour them a beer. Even we shouldn't follow Wittgenstein by explaining "I'm thirsty" exclusively in terms of its role in the language-game, we shouldn't exclusively focus on subjective experience either. I'd suggest that we should take an intermediate position instead.

In this section we discussed how The Investigations serves as a reminder not to take things too literally. This is a trap that rationalists often fall into, my past self included.

The Private Language Argument

The Stanford Encyclopedia of Philosophy (SEP) describes the private language argument as claiming the impossiblity of a language that is "in principle unintelligible to anyone but its originating user".

Attempting is discuss this argument is extraordinarily difficult. As SEP says, "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"

A significant part of the debate seems to concern whether Wittgenstein is claiming that there is something we cannot do (ie. produce a private language) or whether he is claiming that the concept of "private language" is nonsense. However, I don't see a need to focus too much on this distinction, so we'll move on. 

SEP also suggests that Wittgenstein might be responding to Bertrand Russell's ‘The Philosophy of Logical Atomism’:

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.

... 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.

Bertrand Russell hoped that it might be possible to construct a logically perfect language. This would be build it up from simple objects of sense-datum rather than external, physical objects presumbaly because of the inherent uncertainty in deriving what actually exists from sense data.

Note that Bertrand Russell conceded that his position meant other people wouldn't understand the proposition that he meant by "This is white" and that the meaning of that proposition would change from moment to moment.

Compare this to Wittgenstein's beetle-in-a-box thought experiment:

Now someone tells me that he knows what pain is only from his own case!——Suppose everyone had a box with something in it: we call it a "beetle". No one can look into anyone else's box, and everyone says he knows what a beetle is only by looking at his beetle.—Here it would be quite possible for everyone to have something different in his box. One might even imagine such a thing constantly changing.—But suppose the word "beetle" had a use in these people's language?—If so it would not be used as the name of a thing. The thing in the box has no place in the language-game at all; not even as a something: for the box might even be empty.—No, one can 'divide through' by the thing in the box; it cancels out, whatever it is.

There seems to be very little difference between their positions. I suppose, as they say: one man's modus ponens is another man's modus tollens, although perhaps Russell would dispute that the "thing-in the-box" has no role in the language-game. After all, even if we can't be sure that our sensations are the same as that of other people, searching for a sensation seems to be part of how we understand when to use these terms.

For example, when learning to taste wine I might take a sip, but miss a flavour because I'm distracted by other flavours and then only notice the flavour I was supposed to note upon taking another sip. If repeated attempts at tasting the flavour failed to detect it, I might wonder if there was something unusual about my taste receptors or whether I just wasn't paying close enough attention during the tasting. Wittgenstein would undoubtedly describe this process as a language-game without any reference to this private sensation, but I would see this as a reductive account that has leaves out a core part of the phenomenon.

Wittgenstein's definition of knowledge is key to his argument for private languages being impossible. If we accept his argument that we can't have knowledge of internal sensations, then anything that private language could communicate would be of dubious authenticity. I've already explained my skepticism of his epistemology which leads me to also be skeptical of the private language argument.

Relevance: His private language argument is probably the aspect of his philosophy that I am most critical of. Nonetheless, I think there is an important insight here. We shouldn't just take statements at face value, but rather we should always keep in mind the language-game that is being played and what function the particular use of language serves. In the section on Subjective Experiences we discussed how talk of internal feelings is sometimes just the surface-level discussion.

The episode of In Our Time that focused on Wittgenstein containing an interesting reframing of his private language argument. We often see language as something in which we dress our pre-existing thoughts in order to express them to others. However, participating in language-games with others is a key part of how we acquire the concepts and distinctions we make use of during thinking. Given this, we would expect that an individual who spend their whole live isolated from others would, at best, only be able to produce a severely impoverished form of thought and hence language.

I've previously used the term linguistic freedom [LW · GW] to describe the freedom that we have to define or redefine words to suit our purposes. This is related to the idea that the Map is Not the Territory [? · GW] as once we have realised that we construct the map, it is natural to assert the freedom to draw the map differently in order to better suit our purposes. At a number of points, Wittgenstein seems to argue for this kind of linguistic freedom:

What about the colour samples that A shews to B: are they part of the language? Well, it is as you please.


But how we group words into kinds will depend on the aim of the classification,—and on our own inclination

Logic and Maths

Wittgenstein criticises the idea that logical statements are true a priori:

We want to say that there can't be any vagueness in logic. The idea now absorbs us, that the ideal 'must' be found in reality. Meanwhile we do not as yet see how it occurs there, nor do we understand the nature of this "must". We think it must be in reality; for we think we already see it there.

In other words, don't just assert that logical statements "must" be true without understanding why you think they must be true.

But: if anyone believes that certain concepts are absolutely the correct ones, and that having different ones would mean not realizing something that we realize—then let him imagine certain very general facts of nature to be different from what we are used to, and the formation of concepts different from the usual ones will become intelligible to him

Perhaps we lean towards classical logical because we exist at the macro scale, but if we were to exist at the quantum scale we'd free notions of logic that allow things to be both true and false.

Of course, in one sense mathematics is a branch of knowledge,— but still it is also an activity. And 'false moves' can only exist as the exception. For if what we now call by that name became the rule, the game in which they were false moves would have been abrogated.

We consider it a mistake to say that 2+2=5. However, let's suppose we ended up adopting this rule. Presumbably that's because we've discovered facts about the world indicate that this system of maths is more applicable than ours. Then it wouldn't be completely accurate to say that 2+2=4 was wrong. It was correct within the language-game that we were playing. What happened instead is that we decided to play a different language-game - one where 2+2=5.

For the crystalline purity of logic was, of course, not a result of investigation: it was a requirement

We think logic must necessarily be true because we cannot think of any examples where it is false. But of course, if we could have thought of any counter-examples, then we wouldn't have constructed the rules of logic this way.

I think the Liar's Paradox is instructive here. It's very common to think that statements that aren't nonsensical must be true or false. However, the Liar's paradox explodes this. Has this caused anyone to abandon logic?

Of course not! Everyone just updates their schema by excluding Liar sentences from this requirement. And then they make further adjustments in reponse to the extended Liar's paradox. This is much more what we'd expect from a system of ad-hoc patches than a priori knowledge. And perhaps we can't think of any counter-examples to logic because if we could then logic would have already been adjusted to be compatible with this.

Mathematicians do not in general quarrel over the result of a calculation. (This is an important fact.)—If it were otherwise, if for instance one mathematician was convinced that a figure had altered unperceived, or that his or someone else's memory had been deceived, and so on—then our concept of 'mathematical certainty' would not exist.

Mathematical "certainty" doesn't exist absolutely, but only under certain conditions.

Relevance: Wittgenstein has influenced me towards adopting a more grounded and embedded notion of what maths and logic are. I used to be quite tempted by Mathematical Platonism, but Wittgenstein argues rather persuasively against maths and logic consisting of a priori truths.

Conceptual engineering [LW · GW] is the idea that instead of asking what a word means, we should be constructing words that serve particular purposes. It is often contrasted to conceptual analysis to attempt to find necessary and sufficient conditions for being a part of a particular class and in particular tries to avoid the existence of any counterexamples.

I suspect that if analytical philosophy had placed more emphasise on Wittgenstein that they wouldn't have fallen into the trap of counter-example philosophy that arose from conceptual analysis. LukeProg describes the problem as follows:

The trouble is that philosophers often take this "what we mean by" question so seriously that thousands of pages of debate concern which definition to use rather than which facts are true and what to anticipate.

While as far as I know, Wittgenstein doesn't explicitly argue precisely for conceptual engineering, it seems to arise naturally from his philosophy. Firstly, his model of words as family resemblances suggest that it'll be impossible to find necessary and sufficient conditions that avoid all counterexamples. Secondly, his model of language as use seems to suggest that what is important about words is the purpose that they serve. Thirdly, his argument for language-games and a kind of linguistic freedom seems to suggest that we have the ability to collectively define and redefine conventions about how words are used in order to make them more convenient for us. Lastly, Wittgenstein even compares the different functions of words to the different tools in a toolbox.

Should you read this book?

I am a huge fan and would strongly recommend it, but be aware that the text is deceptively difficult to make your way through. It is best read slowly. My reasons for recommending this are as follows:


Comments sorted by top scores.

comment by Astor · 2021-10-13T18:06:39.164Z · LW(p) · GW(p)

I don't know if Wittgenstein was the originator of this concept, but he seems to have made it more prominent.

I suppose the pragmatic maxim is also related to this. I always wondered, if Wittgenstein read Peirce's argument in regard to metaphysics.

I really like your review, but I have to admit that I do not like Wittgenstein's concepts. I am simply not sure how to use them in any meaningful way. Unfortunately this has not changed after reading your text.

For example, for me, J. L. Austin explained the whole "language as use" philosophy way better in "How To Do Things With Words" and in most cases I refer to the concept of Sprachdynamik as the principle theory of language change and development, rather than mentioning "language-games". Language-games reinforce the elusiveness of concepts, words and language as a whole. But if you want to use language to do something you have to hold onto at least some meanings.

This contrasts your last section and I do not know how you arrived at your conclusions. Your arguments seem to refer to the elusiveness as a possible building block for ones own definitions. But this seems to be exactly what analytical philosophers try to achieve, or not? They try to find the best possible definition which can be applied to hopefully all but practically most situations. The mentioned difference between conceptual engineering and analysis does not convince me.

Family resemblances also seem to be only useful in denying problems: I cannot find a simple definition for some widely used word therefore it must be a family resemblance and not further be investigated. I am not so sure.

In his argument against private languages I cannot even understand what he means by the word language. His example for a private language is something that is fully untranslatable like the sensations of emotions. But what exactly does it mean to speak of sensations as a private language? What?

This is really unsatisfying. So for me, Wittgenstein is just one of the lesser concept manufacturers, who had luck in getting referenced over and over again. But don't take my word on this! Maybe other people have more luck with these concepts!

Replies from: Chris_Leong
comment by Chris_Leong · 2021-10-14T02:36:35.599Z · LW(p) · GW(p)

Hmm... I can't seem to find an English description of Sprachdynamik.

"They try to find the best possible definition which can be applied to hopefully all but practically most situations" - I guess that often this activity proceeds without a proper understanding of the limitations. For example, if concepts are family resmblences, then we shouldn't be surprised if any definition has a counter-example.

"In his argument against private languages I cannot even understand what he means by the word language" - I understand him as claiming that we can't set up an reliable, intersubjective system of discussing these internal experiences as other people can't perform the error checking function that they can in normal language.

Replies from: Astor
comment by Astor · 2021-10-14T11:27:59.051Z · LW(p) · GW(p)

It is a shame that the book about Sprachdynamik is not translated into other languages. It is also an introduction to the modern Regionalsprachenforschung (science of regional and minority languages). But it is mostly about the concept that there is a synchronization effort between the competency of performing utterances (not just words, but grammar and speech patterns too) on different layers. The micro layer focuses on individual adjustments to the utterances you are hearing and reading each day. The meso layer is about recurring events like work or peer groups. And the macro layer focuses on culture defining moments like the publication of the bible. Here is a research paper (unfortunately in German, but you could translate it via Google Translate, if you want to go deeper) that uses Sprachdynamik to analyze the German minority language in Hungary by the Goethe institute. Unfortunately, I am not so well read on the international discourse. But for me it is a sufficient theory of language change and development.

I thought the analysis is the part about finding out the limitations of concepts. Of course, it can be useful to be careful with your definitions and expect that you do not find anything. But I am not so sure, if this contrasts all of analytical philosophy because you have philosophers like Popper or Russel who try to be very careful in applying their concepts. And many philosophers are very self-critical in their efforts.

I understand him as claiming that we can't set up an reliable, intersubjective system of discussing these internal experiences as other people can't perform the error checking function that they can in normal language.

I really like this description, this is a possible stepping stone for the introduction of the mind-body problem. But there is also the possibility of him denying these sensations in their entirety because they cannot be translated and do not have a function. For me, this is the part of having a box with no beetle at all: "it cancels out, whatever it is" (which would be a linguistic interpretation of monism). Is this a possible or an accurate interpretation of his thought experiment? I do not know because for him linguistic definitions seem to be unreachable. This is the unsatifying part for me. I am not sure, if I am getting it and I do not want to imply that I am. So I do not try to challenge these concepts. I can only say that I do not like them because they do not offer me more insights with the interpretation I have of them.

Replies from: Chris_Leong
comment by Chris_Leong · 2021-10-14T12:38:40.598Z · LW(p) · GW(p)

Thanks for the description

Is this a possible or an accurate interpretation of his thought experiment?

As far as I could tell from reading the book, Wittgenstein was trying to avoid taking a stance on whether or not these internal sensations exist or not. However, he strongly emphasised that he wasn't claiming they don't exist.

Replies from: Astor
comment by Astor · 2021-10-14T14:50:42.237Z · LW(p) · GW(p)

Possibly. Is this your interpretation of the paragraphs 304 and 307? But which arguments can he use to assert that, if he argued previously for not knowing definitively? I really enjoy your takes on this. I hope this is also kind of fruitful for your endeavors.

Replies from: Chris_Leong
comment by Chris_Leong · 2021-10-14T15:11:44.056Z · LW(p) · GW(p)

It's my overall impression. He revisits the topic a lot.

But which arguments can he use to assert that, if he argued previously for not knowing definitively?

I don't think he took a position. I just meant that he puts more emphasis on avoiding people mistakenly thinking he is claiming internal experience don't exist than he does on avoiding people mistakenly thinking that he is claiming they do exist. Presumably because he was more often attacked for the former.

Replies from: Astor
comment by Astor · 2021-10-14T15:19:14.880Z · LW(p) · GW(p)

I see, thank you for that and thank you for the conversation.

comment by Samuel Shadrach (samuel-shadrach) · 2021-10-13T04:57:07.760Z · LW(p) · GW(p)

Thanks for the review!

Quick feedback, it's a bit long, I only read half, I'm sure I'm not the only one.

But otherwise definitely a good review.

Replies from: Chris_Leong
comment by Chris_Leong · 2021-10-13T05:47:34.589Z · LW(p) · GW(p)

Thanks! Yeah, it's definitely really long and if I had more time it would have been even longer!

I guess if I'd written a shorter review I would have either skipped key aspects of his work, had less space in which to help clarify his frames or not been able to explain why his ideas are relevant to rationalists.

I have a bit of duplication, but figuring out how to remove that would be challenging.