I don't do any calculus when I'm catching a ball - I "just know" where to put my hands. Some people talk about "judgement". One supposes that my brain is doing the calculations sub- or un-consciously. I guess my brain is doing some work, but doubt that it is doing calculus calculations — Ludwig V

I agree! And yet the output is the same as if it had been doing calculus. That suggests something interesting (though I can't say exactly what...!)

Reminds me of Wittgenstein's 'Philosophical Investigations': 'Calculating prodigies who arrive at the correct result but can’t say how. Are we to say that they do not calculate?'

However I think it is more plausible to suppose that it is using some quick and dirty heuristic, which, no doubt, would give mathematicians a fit; but evolution only cares what works well enough. The same, I would think, for the dog. — Ludwig V

What's interesting here is that sometimes our 'subconscious' mental calculations are not quick and dirty – they are enormously precise and accurate. A good example might be professional snooker or pool players. They are capable of modelling physics interactions to extraordinary degrees of specificity. Their models are probably superior to purely mathematical models in terms of predictive accuracy. But they do not consciously perform calculations at all.

More realistic sounding to me is that dogs (and people) use a gaze heuristic.. — wonderer1

I'm not sure if you read the paper I attached, but the dog's actions cannot be explained by applying the gaze heuristic, because that heuristic deals with tracking moving objects. The dog is not tracking a moving object, but rather charting an optimal path to a fixed point over two varied surfaces (land and water). In order to work out that optimal path using mathematics, we need calculus. The dog finds the same path without resorting to calculus (we assume). But the gaze heuristic would not be of any assistance.

This interesting thread put me in mind of a fun paper I read many years ago, called 'Do Dogs Know Calculus?'

A mathematician shows that his dog, when fetching a ball thrown into water, appears to be calculating the optimal path from A to B as if using calculus. But, of course, calculus is computationally tricky even for most non-expert human beings. A dog cannot know calculus. Can he?!

I do want to comment on what I was saying about hinges in relation to Godel's proofs. All I was trying to say is that instead of looking at certain axioms within a particular system as something that can't be proven within the system, we could look at them as endpoints not needing proof or justification, like Witt's hinges. — Sam26

But we don't choose to 'look at axioms' as 'something that can't be proven within a system' – that is what axioms are (it is simply what the word 'axiom' means). The unprovable statements – or 'Godel sentences' – theorised in Godel's incompleteness theorems are not axioms.

Axioms are indeed something like Wittgenstein's 'hinges', in that we accept them without proof and they form the basis of a system of reasoning. But that has nothing to do with Godel or his theorems.

It also seems on the face of it very strange to describe 'hinges' as 'endpoints'. The whole idea of a 'hinge' is that it stays in place so something else can productively move or turn. If Wittgenstein had meant to conjure up the idea of an endpoint, he could surely have chosen a better metaphor than 'hinge'.

I think this idea has ramifications beyond epistemology. I think it solves the problem posed by Godel's two theorems. These hinge beliefs seem to exist in any system where proofs are required, whether epistemological or mathematical. This of course goes beyond anything Witt talked about in OC, but I think it has merit. — Sam26

I'm not sure what 'problem' you suggest is being solved here. What is the 'problem' posed by Godel's theorems? As I understand, the theorems are in fact quite useful and have practical applications in fields like computer science. No doubt, Godel's work poses problems for earlier mathematical projects like Hilbert's programme. But in contemporary mathematics, as far as I understand (not being a mathematician myself), Godel's work is not really a 'problem' to be 'solved'.

Further, the semantic counterpart to the unprovable statements in Godel's incompleteness theorems would not be anything like a 'hinge belief'. It would be something more like the liar's paradox – a self-referential statement that cannot be both true and provable at once. Godel himself used the example of the liar's paradox in the introductory section of his paper advancing the incompleteness theorems. Wittgenstein responded to that example directly in his 'Remarks on the Foundations of Mathematics'.

As my understanding goes, contemporary mathematicians generally do not consider Wittgenstein's reading of Godel useful. I am not a mathematician and cannot claim to understand the mathematical implications of Godel's work or the validity of Wittgenstein's response. But I am cautious of philosophical theories that claim to 'solve', refute, or have other decisive implications for complex theories in fields like physics or mathematics.

Because the authors were not talking about gloves with palms and backs. They were specifically providing examples of gloves that had no distinct indicators that they were for left or right hands. Think of disposable plastic gloves that medical providers use if that helps. — Philosophim

That makes perfect sense – sorry for misunderstanding. But in the case of those sorts of gloves, there are no ‘left’ or ‘right’ gloves, any more than there are ‘left’ or ‘right’ socks. I don’t see why we need to imagine the glove floating in an empty container. Nor would the addition of a human spectator answer the question of whether it is a left or right glove – it is neither.

Ok, so the glove can fit a right hand or left hand — Philosophim

I'm not sure I follow. As Banno says:

If the gloves have palm and back, then you can certainly tell which is left and which is right. — Banno

Gloves look very different depending on which hand they are supposed to fit.

If the question is whether 'left' and 'right' exist independently of any specific spatial observation point, I can't imagine how they could. What would anything be 'left' or 'right' of? They are relational terms. But I sense I'm misunderstanding a deeper philosophical question.

As it happens, I am one of those unfortunate souls who often gets confused between left and right. But, of course, I never confuse 'up' with 'down' or 'backwards' with 'forwards'. (Not that I'm suggesting those directions are any more independent of an observer! Just an observation).

Yeah, to some extent the hinge is just the stuff we agree on, but there is an extra step such that the hinge is the stuff about which we cannot sensibly disagree... — Banno

I think this is a good point. There is something more to 'hinges' than just 'the presuppositions we agree to adopt'. And it has to do with whether disagreement could be meaningful within the terms of our game. But I think beyond that, 'hinges' have been over-theorised in comparison to their importance in the broader line of inquiry in 'On Certainty'.

What you say here is very clear and succinctly put. It makes sense to me that an adverb functions differently from a noun phrase and raises different questions.

The problem with Ayer's direct/indirect seeing is not that he is stating something self-evident, but that he is saying something obscure. — SophistiCat

Thank you – you've really helped to clarify this problem for me. And as I suspect there was nothing in here that needed clarifying from your point of view, I'm grateful to you for taking the time to explain!

An important difference between Gödel and Wittgenstein is that for the latter the synonymous concepts of hinge propositions, forms of life and language games are neither true nor false. They are outside all schemes of verification, since such schemes presuppose them. — Joshs

Axioms in a formal logic system are also outside all schemes of verification, because they are presupposed and form the basis on which those schemes proceed. Whether or not axioms are 'true' is, as I understand, an open question in the philosophy of mathematics. From this thread, I gather that the truth-value of 'hinge-propositions' is an open question in philosophy too.

Again, I fail to see a distinction between the 'hinge-propositions' that are being discussed here and the simple concept of axioms – claims we accept without proof in order to begin reasoning in the first place. But I also admit I do not recognise Wittgenstein as having theorised anything called a 'hinge-proposition' in 'On Certainty'. I accept that he used a door hinge as a metaphor for the way we reason, in sections 341 and 343 and again in 655. But the metaphor was not very thoroughly pursued in any of these cases, and did not strike me as particularly crucial to his line of inquiry.

Of course, the academic consensus would strongly suggest I'm wrong – that 'hinge-propositions' do indeed form a key part of Wittgenstein's argument in 'On Certainty'. I just can't seem to make that out in the text itself.

Thanks for this.

My point is that if we think of the propositions in Godel’s theorem (the ones that cannot be proven within the system) in the same way Wittgenstein thinks of hinge propositions (basic beliefs), viz., that hinges are outside our epistemological framework, then there is no requirement to prove the propositions within the system. We could think of Godel’s unprovable statements as hinge-like. So, Godel’s unprovable statements are necessary for the formal system to operate, just as hinges are necessary for our epistemic practices. — Sam26

But again, this formulation of 'unprovable statements' that are 'necessary for the formal system to operate' makes them sound more like axioms. How do they differ from axioms?

As far as I can see, there has never been a 'requirement to prove the propositions' that 'are necessary for the formal system to operate' either in Godel or elsewhere – those propositions are axiomatic and Godel did not try to prove them or to show that they could or could not be proven.

Godel showed that there would always be true but unprovable statements within any axiomatic logic system. If these statements are incorporated into the system as axioms (which are precisely those statements that are accepted as true without being proven), either those new axioms will contradict the existing ones, or they will result in the emergence of further true but unprovable statements. No system can ever fully incorporate all these true statements as axioms and remain consistent.

Again, I'm not a mathematician. But what you describe as 'hinge-propositions' sound a lot more like axioms (which form the basis of reasoning) than true but unprovable statements (which are not axiomatic).

I’m assuming you understand Wittgenstein’s point about hinges in OC. — Sam26

Thank you, but that's probably too charitable an assumption! To be honest, after reading 'On Certainty', I was surprised to find such widespread discussion of 'hinge-propositions' in the secondary literature. Wittgenstein only mentions hinges briefly and never seems to use the phrase 'hinge-propositions' at all (at least not in the Anscombe/Wright translation, unless I'm mistaken).

In section 655 he writes:

The mathematical proposition has, as it were officially, been given the stamp of incontestability. i.e.: "Dispute about other things; this is immovable – it is a hinge on which your dispute can turn."

He's talking about the proposition 12x12=144 here, which can be derived from basic axioms of arithmetic. I don't see how this relates to Godel's theorems but, again, no doubt there is much I don't understand here.

eta: I realise I've taken the above quotation out of context. But it comes from a section where Wittgenstein is teasing out certain epistemic similarities between mathematical propositions and empirical propositions. From 651:

... one cannot contrast mathematical certainty with the relative uncertainty of empirical propositions. For the mathematical proposition has been obtained by a series of actions that are in no way different from the actions of the rest of our lives, and are in the same degree liable to forgetfulness, oversight and illusion.

And 653:

If the proposition 12x12=144 is exempt from doubt, then so too must non-mathematical propositions be.

That's the context in which I understand the idea of 'incontestable', 'fossilised' or 'hinge-like' propositions in 'OC'.

The foundational axioms act as hinges in the Wittgensteinian sense. This would eliminate Godel’s requirement for the axioms to be proved within the system. — Sam26

I confess I don't have a background in mathematics, but I'm not sure I follow you here. As far as my understanding goes, Godel's incompleteness theorems do not show that a formal system of logic cannot prove its own axioms. That axioms cannot be proven by deductions from axioms is a foundational principle of mathematics and logic, and did not originate with Godel.

The incompleteness theorems show that formal systems of logic always produce truths that are not provable using only the axioms of the system. Even if those truths are adopted as axioms, further unprovable truths will still exist, generating an infinite list of axioms. If a given axiom ever makes that list 'complete', then the list can no longer be 'consistent', in the technical mathematical sense of those terms.

The truth-value of axioms in themselves is a question in the philosophy of mathematics (and philosophy generally). But your treatment of Wittgenstein's 'hinge-propositions' here effectively equates them with axioms – which is to say, claims that are accepted without being proven and on the basis of which formal logical reasoning depends. That is the basis of all formal reasoning, as far as I know, and not original to Wittgenstein or Godel.

Am I missing something? If Witt had meant that hinge-propositions were just like axioms, he would have said so. He had a good knowledge of mathematics, as I understand. But perhaps you are a mathematician too and you can explain where I'm going wrong here! Thanks in advance.

Ok, so is there any evidence that Austin explicitly accepted the Contrast Theory of Meaning? — Banno

I feel we're talking past each other now. As I have said many times, I am not attributing the theory to any particular philosopher. I'm interested in whether or not the theory holds, in itself. From my post above:

You are concerned with defending the ordinary language philosophers from the allegation that they ever propounded this theory, and I accept and understand that. But I think there is some value in taking the theory on its own merits and trying to assess whether it stands. — cherryorchard

If you are only interested in arguing that Austin (or Wittgenstein, or anyone else) never advanced this theory, I have already accepted as much. I just want to discuss the theory as it has been described.

Sorry, I didn't see this second reply.

It does not pay to assume that a word must have an opposite, or one opposite

By my reading, what Austin is saying here is that a word need not have an antithesis that is summed up neatly in an opposite word. And 'shoe' is a good example – we don't have or need a single word that means 'non-shoe'. The word 'shoe' does all the work itself. But it still depends on the category of 'things that aren't shoes' in order to be a meaningful word. If it did not exclude non-shoes, it would not be doing the work of the word 'shoe'.

Seems to me that there is a difference between holding that every use of a word is dependent on a contrast and holding that this use of a word is dependent on a contrast. — Banno

I understand that's your position. I suppose I could reply that Wittgenstein and Austin selected specific words for discussion because they felt that those specific words were being misused for philosophical purposes without a meaningful antithesis. Again, from 'On Certainty': 'If you tried to doubt everything you would not get as far as doubting anything.'

But the same argument could apply to words generally. The word 'shoe', for instance, obviously gets its meaning from the fact that it refers only to things that are shoes, and not to things that aren't. 'If you tried to call everything a shoe, you would not get as far as calling anything a shoe'. But there was no need for Wittgenstein to say so, because nobody was going around calling everything a shoe for philosophical reasons.

I am not attributing this theory to any one philosopher in particular, but I am interested in whether or not it holds. Gellner's critiques of the theory don't make sense to me, and I'm trying to work out whether that's my problem or his. You are concerned with defending the ordinary language philosophers from the allegation that they ever propounded this theory, and I accept and understand that. But I think there is some value in taking the theory on its own merits and trying to assess whether it stands.

Can anyone think of any word that is meaningful without a contrast? I haven't seen an example yet.

Thank you for the response.

These strike me as good points and good philosophizing. — Leontiskos

That's very kind. At the start of the thread, I felt I was making a bit of a fool of myself. So I'm glad to know I'm not talking total nonsense!

Perhaps, but there are probably more contemporary and focused treatments of the subjects that interest you. With that said, Aristotle is great once you get the hang of him. — Leontiskos

If you can think of any particularly interesting contemporary accounts of these questions, I'd be very happy to look them up.

I'll maintain that it is up to Gellner to show that they held such a view, rather than up to us to show that they didn't. — Banno

I have provided a few specific examples where Austin and Wittgenstein argued that an absence of contrast (or antithesis) rendered a word meaningless. Ludwig V also cited Ryle's example of the counterfeit coins.

Of course, these examples are specific to particular words, and not expressed in terms of a general theory. Still, it's hard to imagine what sort of word this logic would not apply to – a word that would be meaningful even while lacking any contrast. Can you think of one?

I sense you may reply that the onus is not on you to think of an example that violates the 'contrast theory', but on Gellner to prove that the theory was ever actually proposed by the philosophers he is criticising. Fair enough, but the initial aim of my post was to consider his critique of the theory as he expressed it.

Thanks for the response!

I'm sorry. I can't work out exactly what you mean. Can you give an example - or two? — Ludwig V

Again, I'm sorry for being unclear. I'm talking about statements like 'all x are y' or 'x is always y' – claims about x that admit of no exception. My first example was 'we only ever see indirectly' – a claim that 'seeing' is always, with no exception, indirect. And my second example was the one you raised: 'all bachelors are unmarried'. These are both claims that admit of no exception. But to me, one of them seems like nonsense and the other one seems meaningful (in a limited way). I'm trying to work out why that is.

Austin gives an example I think is helpful. But I can't remember the details, so I'll adapt it. Air traffic control radar shows a blip on the screen, with the flight number attached on a little label. The controller says "I can see flight 417", and so he does, but the visitor who peers anxiously out of the window is puzzled. The controller can see flight 417 indirectly. The visitor thinks the controller meant directly. Clearly, seeing flight 417 through the window is seeing it directly (despite the fact that it is through the window). Suppose the visitor gets out a pair of binoculars, sweeps them round a bit and says "Aha! There it is!". Does the visitor see flight 417 directly?
The last point - the unanswerable, doubtful case is quite important to me. There's no point in pretending that this stuff is cut and dried.
Now think about why you gave the answer you did give to each case. I think you'll find you understand how directly and indirectly could be applied in this case. I agree I don't think it would help anyone who doesn't already know what "see" means, but it does help us, in our situation, so that's all right.
Austin does raise the question why anyone would worry about the difference in normal life - did you feel the same when you read the example? He's sort of saying that, despite the example, he's not at all sure that "direct" and "indirect" to "see". — Ludwig V

I'm not sure I understand this. Seeing something represented on a monitor may be a way of seeing it 'indirectly'. Seeing something in a mirror is another example – e.g., 'From where I was sitting, I couldn't see the door directly, but I could see it in the mirror.' That sounds like ordinary language to me.

'I couldn't see the airplane directly but I could see it with my binoculars' does not strike me as a familiar use of the word 'directly'. If you wanted to explain that you could only see the plane with binoculars, you might say something like: 'it wasn't visible with the naked eye'. The word 'directly' wouldn't ordinarily be used like that. But I suppose if someone was just chatting and not being mindful of how they expressed themselves, they might say 'I couldn't see it directly'.

All that said, I'm not sure where this gets us. The fact that we can think of uses for the words 'directly' and 'indirectly' as applicable to 'seeing' doesn't seem to clarify whether it's meaningful to say something like 'we only ever see indirectly'. I suppose elucidating the specific usage suggests that 'directly' and 'indirectly' only work in contrast to one another. But it doesn't prove as much. Or does it?

Take any analytic statement, "All bachelors are unmarried" is a nice stock example. It is not possible for any bachelor to be married. It is contrast free. Ryle's examples below don't apply and Gellner has a case for saying that this is an example of a contrast-free statement, and, in a sense, it is. But that isn't paying attention to the kind of statement it is, and to the point that of course there are some people who are not bachelors. It's just that there are no married bachelors. — Ludwig V

This touches on what I tried to articulate earlier in the thread (with my very silly analogy about the coffee machine). Sometimes, universal statements about a particular term are meaningful. But why is that so?

Maybe it's because the sentence 'all bachelors are unmarried' is a way of defining the term 'bachelor'. We can think of people who aren't bachelors, and people who aren't unmarried, so these terms make sense. And by conjoining them, we learn something about what the word 'bachelor' means. (In fact, 'bachelors are unmarried' does sound like something you might really say to someone who wasn't sure what the word 'bachelor' meant – a child or a language learner, e.g.).

'We only ever see things indirectly' doesn't offer a definition of the term 'seeing'. And while the word 'indirectly' does have a hypothetical antithesis ('directly'), it's very hard to see how that might apply to anything in this specific case. Someone who wasn't sure what the word 'see' meant would not be helped along if we told them 'we only ever see things indirectly'.

Only in the second instance do we run up against the lack of a meaningful contrast. 'Seeing directly' rears its head whether we like it or not. The spectre of a married bachelor doesn't really haunt us in the same way, does it? Bachelors can get married, and then they stop being bachelors and become married men. But seeing can't stop being indirect and then become something else.

I'm not sure this deals conclusively with the problem, though...

In any case, thank you for the quotation from Ryle! I will look up that book.

Thanks for this reply.

(The Contrast Theory when made explicit leads to a neat paradox; on its own grounds, a language should sometimes be usable without contrast, so that "contrast" may have a contrast.)
That's a kind of argument that's very popular with philosophers, because it is a slam-dunk. Unfortunately, such arguments are usually mistake, because they have over-simplified the issue. — Ludwig V

I'm interested that you call Gellner's 'paradox' argument a 'slam-dunk'. I confess I can't make sense of what he means at all. 'Words function through contrast with an antithesis' seems like a perfectly valid and meaningful theory of how words function. There are no words in the theory that lack an antithesis. But Gellner seems to suggest here that the theory requires not only that words have antitheses, but also that all theories have meaningful exceptions. Why should it require that? I can't see how it follows logically.

Another possibility is that he is picking up on an argument of, I think, Ryle, that it is not possible for all coins to be fake. If there is no such thing as a real coin, there is nothing to fake and so "fake" has no meaning. As I remember it, this was intended to apply to sense-datum theory, because that theory essentially claims that my belief that everything that I see is a three-dimensional object located in space-time is an illusion. In this case, at least, "fake" or "unreal" are defined in relation to "genuine" or "real", so there is a contrast here. — Ludwig V

This is interesting, thank you. I haven't read Ryle – do you remember where this idea comes up in his work? It strikes me as reminiscent of passage 345 in Wittgenstein's 'Philosophical Investigations':

“If it is possible for someone to make a false move in some game, then it might be possible for everybody to make nothing but false moves in every game.”—Thus we are under a temptation to misunderstand the logic of our expressions here, to give an incorrect account of the use of our words.
Orders are sometimes not obeyed. But what would it be like if no orders were ever obeyed? The concept ‘order’ would have lost its purpose.

I think this is the sort of thing Gellner is objecting to in 'Words and Things' (as opposed to, for instance, logical positivism). But I think Wittgenstein's point here is coherent and convincing, whereas I can't understand what Gellner means at all.

Thanks for this reply – again, very helpful.

What the proponent of indirectness might say is that when we "drive" our body we are doing so directly, and in comparison to this driving a car is indirect. — Leontiskos

I think this would be toying with language a little too freely. In English at least, we don't 'drive' our bodies, we 'move' them. And in fact, we usually don't even 'move our bodies' – we just 'move'. The body is the subject, not the object. 'Driving' always applies to our movement of things other than ourselves ('driving cattle', 'driving him away', etc.).

Now I sound like I'm doing an impression of JL Austin. But whatever about 'driving', I do think words like 'see', 'sense', and 'perceive' require a lot of specificity and care to avoid descending into nonsense.

Usually when this topic comes up on these forums the proponent of indirectness ends up being pushed in the direction which says that we directly see our sensations and impressions, and then we infer from those sensations something about the external world. It would be a bit like if you received an encrypted message, and once you decrypted it you would possess information about the external world. As far as I can see, the correct response to this idea is that sight does not involve anything like this inferential process, and that to go further and talk about subconscious inference places us in very dubious waters. — Leontiskos

Yes, this is the argument I've encountered – and I've also seen its proponents claim that this is the model of perception best supported by scientific research. I have to say, I find this theory more perplexing than wrong. I don't think I really understand what it means. But I can't tell whether that's because there is something not-quite-meaningful lurking inside it, or I'm just failing to understand what it says.

We all understand and accept that different creatures with visual organs perceive the world differently. Only certain wavelengths of light are perceptible to human eyes, etc. So of course there is no 'one' objectively correct way of seeing the world. And sometimes we are subject to illusions, delusions, hallucinations, and so on. But I don't understand the leap from these clearly acceptable claims to the claim that we don't see material things at all. Where does the 'sense-data' come from, if not from the world outside? And if it does come from the world outside, what are we arguing about? The work we have to do to interpret it once it arrives? But that seems to me like a completely different question.

From your posts, I'm starting to think that what I really need to do is read Aristotle's Metaphysics...

I sense that your discussion has taken a different line from the rest of the thread, but I feel I should chime in here to say that I don't think Austin made any specific claims about realism (direct or indirect) in 'Sense and Sensibilia'. In fact, here is a quote from the first section:

I am not, then––and this is a point to be clear about from the beginning––going to maintain that we ought to be 'realists', to embrace, that is, the doctrine that we do perceive material things (or objects). This doctrine would be no less scholastic and erroneous than its anthesis.

Austin's argument is about what he sees as the misuse of particular words in philosophy. He is not making (or does not see himself as making) arguments about 'realism' (naive, indirect, or otherwise) per se.

I have no academic background in philosophy, so I defer to those who know better, but I don't think proponents of the sense-data theory are necessarily solipsists. Bertrand Russell and GE Moore were among the philosophers who advocated the sense-data theory, and they did not argue in favour of solipsism.

In fact, some version of the sense-data theory seems to be the majority position in contemporary philosophy. (Please correct me if I'm wrong!) But the argument in this thread is not about the existence of external reality as such. It is about whether the 'contrast theory of meaning' is, as Ernest Gellner suggests, a fallacy – whether we can meaningfully make such statements as 'we only ever see things indirectly' or 'we can never be certain of anything'. I don't think my hypothetical friend is necessarily disappearing into solipsism when he takes Gellner's side against JL Austin (and me).

Could you explain what he means by speaking so severely or loosely that there is no real negation? — frank

Thanks for the input. This section in Gellner's book is very brief (only a few pages long) and it's not always quite clear what he means. The example I've been using is a claim made by proponents of the 'sense-data' theory like AJ Ayer. To be very succinct (and therefore maybe inaccurate!) Ayer claims that we never see any material objects directly; we only ever see our own 'sense-data'. For Austin (one of the ordinary language philosophers Gellner is writing about), this is an example of a claim 'so loose, that [...] everything must fall under it. The term then loses any contrast; it is then used "without antithesis".' There would no longer be any such thing as 'seeing directly' – it wouldn't even be possible to imagine what that might be – so to claim that we 'only see indirectly' would be meaningless.

Gellner is trying to argue against Austin (and implicitly for Ayer) in this section about the 'contrast theory'. I'm just trying to get to grips with what exactly his argument is, and why it's wrong.



Leontiskos, thank you for such an excellent summary of my question (and this thread generally). And I apologise for making such a summary necessary – I suspect I haven't been as clear as I wanted to be.

The genus of (1) can be construed as actions, the set which includes things like feeling (pain) and seeing (objects). Within that broad genus one can distinguish feeling from seeing, and argue that to feel is more direct than to see. Whether they are right or wrong remains to be seen, but their distinction is not prima facie irrational. The coherence of the argument depends on the idea that the directness of feeling can be compared to the directness of seeing. — Leontiskos

This is the crux of the matter for me. When I read 'Sense and Sensibilia', I feel that Austin has put the issue to bed altogether. But when I try to imagine myself defending his argument against a sceptic, I do run into this problem.

It seems to me pure nonsense to say 'we only ever see indirectly', because it draws on the image of 'direct seeing' only to deny that such a thing exists. It's a little like saying 'we only ever drive cars indirectly, because we use the pedals and the steering wheel' – that is what driving a car consists of. 'Indirect' (or indeed 'direct') doesn't enter into it, unless there are two varieties of driving (real or imagined) that can actually be classified using those words.

But let's say I have a friend who is a sense-data proponent. He says that his terminology is perfectly meaningful. There are direct experiences (mental and physical sensations, feelings, thoughts) and indirect experiences of the outer world (sights, smells) that come to us through 'sense-data'. He says this contrast between direct and indirect makes those words perfectly valid and useful. I don't agree with him. But I still feel I'm losing the argument.

(Oh, and just for future reference, though I realise it's hardly relevant to our discussion – I am a 'she' rather than a 'he'!)

... For instance, is 'we only ever hear sounds' a meaningful statement? We can't imagine any other way of hearing (or at least I can't). But intuitively, I don't find this statement to be meaningless. Of course, there are things we don't hear and things that aren't sounds. But couldn't a sense-data proponent say there are things we don't see and things that aren't indirect? Just no such thing as direct seeing – as there is no such thing as hearing smells.

Again, I think I am wrong here. I just want to be clear with myself on where I am going wrong.

Thanks for this response – it's extremely helpful.

For me this all goes back to Aristotle's idea that a definition or understanding requires a genus and a specific difference. "Coffee machine" is "A machine" (genus) "that makes coffee" (specific difference). In order to understand a term we must understand how it is alike other things (genus) and how it is unlike the things it is alike (specific difference). — Leontiskos

I suppose what I'm struggling to understand is how exactly we know which sort of term is a 'genus' and which isn't. 'Coffee machine' is quite obviously just a specific example of a 'machine' (so I apologise for the inanity of my example). But then, 'seeing' is perhaps just a specific example of 'perception' or even 'experience', or at least some people could plausibly think so. Sense-data theorists might say something like 'we can feel pain directly, but we can't see material objects directly' – and thus hold that their claim 'we never see directly' still has meaning, because 'seeing' is contrasted with other kinds of 'experience' like feeling pain.

I think the issue is in the particular conjunction of terms. The word 'seeing' has meaningful contrasts, as does a word like 'directly' and a word like 'never'. But the combination of these terms together in the claim 'we never see anything directly' is meaningless because it eliminates the possibility of any contrast. That makes complete sense to me – I'm just still struggling to pinpoint why. Is it because 'seeing' is sui generis, and nothing else is really 'like' it? But is that a subjective judgement?

No, I think you were right the first time when you pointed out that the contrast theory of meaning does not require that the opposite trait be exemplified for the exact same object under discussion. A meaningful word should pick out a particular instance or species (a "non-empty proper subset," as mathematicians would say) from the universe of discourse. In this case, the universe of discourse would include all kinds of machines (or all kinds of things), and we can readily come up with examples of machines or things that do not make coffee. — SophistiCat

Thanks for this! I thought I was right the first time too... It intuitively makes sense to me that 'we can never see material things directly' is not a meaningful claim. And I found Austin's discussion of this sort of claim in 'Sense and Sensibilia' very persuasive. It was only afterwards that I started worrying I hadn't really understood what he was saying.

It's not that I think anyone on this thread is wrong and Gellner is right. I found Gellner's argument unconvincing. I'm just trying to understand why 'we never see material things directly' is qualitatively different from a claim like 'we only ever digest what we consume'. It is hard to imagine any other kind of digestion, but that doesn't make that particular statement meaningless. Whereas 'we never see material things directly' seems to be haunted by the ghost of 'direct seeing'.

Some examples might be helpful here. Can it be shown that Gellner addressed Ordinary Language Philosophy, rather than his own caricature of it? — Banno

I did raise that possibility myself in the very next section of the post you quote from.

I also find the argument, as stated by Gellner, to be convincing in itself, so I don't think Gellner is misrepresenting his opponents' views. (But I may be wrong). — cherryorchard

If you think I am indeed wrong, and that Gellner is misrepresenting his opponents, I would love to know how – it would help very much to clarify the muddle I've got myself into.

For my own part, I think Gellner's account of the 'contrast theory' bears a fair resemblance to passages like the following, from Austin's 'Sense and Sensibilia':

… it is essential to realise that here the notion of perceiving indirectly wears the trousers—‘directly’ takes whatever sense it has from the contrast with its opposite

Or even passages like this from Wittgenstein's 'On Certainty':

If you tried to doubt everything you would not get as far as doubting anything. The game of doubting itself presupposes certainty.

In this thread I've mostly been using the example of 'seeing directly' to consider Gellner's argument. But it would, I think, also be possible to consider how the argument applies to Wittgenstein's 'game of doubting' in 'On Certainty'.

Again, I should say that I do think Gellner is wrong. I'm just asking for help in getting my own thoughts straight on exactly why he's wrong. And I appreciate the contributions of everyone who has taken the time to reply!

Thanks for this. I understand Gellner's critique of ordinary language philosophy is wide-ranging and not limited to identifying a few 'fallacies' (of which my post only addresses one). The quotations you select point to more interesting areas of argument (in my opinion) against ordinary language philosophy as a whole – which isn't to say I agree, but I can see there is a good deal of argumentative value there.

But I am stuck on the 'contrast theory' section because I suspect there's something I don't understand about it. Per my reading, Austin spends quite a lot of time in 'Sense and Sensibilia' explaining that there is no point in claiming that we only ever see things indirectly, just precisely because, if that is the case, we no longer have any idea what seeing directly would even mean. There would no longer be any such thing as 'seeing directly'. And thus (Austin argues) the term 'seeing indirectly' when used in this way appears to mean something but actually doesn't. (Wittgenstein might call it 'disguised nonsense').

But maybe Gellner is right that this doesn't hold. If a child asks me what my coffee machine is for, I will explain that it makes coffee. And this explanation strikes me as perfectly valid, even though it is not possible to imagine any other kind of coffee machine. We simply have no concept of what such a machine would be like. That doesn't mean my explanation was wrong, does it? Or that I was using language incorrectly?

Are the sense-data theorists just using the word 'indirectly' to help us to define the way we perceive things? And if something is part of a definition, maybe the contrast rule doesn't apply? We expect definitions to exhaust the conceivable meaning of a term, don't we? So that it's hard to imagine the antithesis, etc.

I feel I am going wrong here somewhere – both when I try to argue against Gellner and when I try to agree with him. But I don't see quite where I am going wrong.