But in Kant, Space and Time are a priori condition for our experience of the external world. He doesn't see them as illusion — Corvus

It wouldn't be an illusion if I saw an Ichthyocentaur, but to think that Ichthyocentaurs exist in the world would be an illusion.

I agree that for Kant, Space and Time are a priori condition for our experience of the external world, and doesn't see them as illusions.

However, there are different aspects to the meaning of "illusion". For example, if I walk outdoors and see an Ichthyocentaur walking along the road, one the one hand this is not an illusion as this is what in fact I see, but on the other hand, I may reason that because of its improbability, this is in fact an illusion .

My innate ability to see the colour red is a prior condition of my ability to experience an external world, but this does not mean that the colour red exists in the external world.

On the one hand the fact that I see the colour red is not an illusion, as I truly see the colour red, though on the other hand I can reason that as the colour red doesn't exist in a mind-independent world, my seeing the colour red is in fact an illusion.

Similarly, one the one hand the fact that I perceive things in time and space is not an illusion, as it is a fact that I do perceive things in time and space, but on the other hand, I can reason that what I perceive is not what exists in the world, and in this sense it is an illusion to think that what I perceive also exists in the world.

An appearance can never be an illusion, though one can reason that the appearance is an illusion.

What do the Indirect Realist say about A priori concepts and space and time? Can these be mind-independent? — Corvus

Does what we perceive as time and space exist outside our perception of it?

I can only see a red postbox because I was born with the innate ability to see wavelengths of between about 400nm to 700nm, meaning that I cannot see ultra-violet, as it has a wavelength lower than 400nm.

It is not so much that I have a priori knowledge of the colour red, but more that I have the a priori ability to see the colour red when looking at a wavelength of 650nm.

I can reason that time exists independently of the mind, but as I can only exist in one moment of time, I can only ever perceive one moment in time. This means that I can never perceive the passage of time, as I can never perceive two different moments in time at the same time.

So our perception of time is an illusion

I can reason that objects such as apples exist in a mind-independent world, but this depends on the ontological existence of spatial relations in a mind-independent world, such that the top of the apple is "above" the bottom of the apple. But the ontological existence in a mind-independent world of spatial relations is problematic, because, although matter may experience forces acting upon it, matter doesn't experience spatial relations acting upon it.

So our perception of space is also an illusion.

As an Indirect Realist, I am not saying that there isn't a cause in a mind-independent of our perceptions, but am saying that what we perceive to be in the world doesn't actually exist in the world. When I perceive the colour red, my reason tells me that there is something in the world that caused me to perceive the colour red, but what is in the world is not how I perceive the colour red. Similarly, when I perceive time and space, my reason tells me that there is something in the world that caused me to perceive time and space, but what is in the world is not how I perceive time and space.

I get the idea that Plato’s appeal to the ‘innate wisdom of the Soul’ can be explained naturalistically with reference to evolutionary psychology...But no other evolved species has the capacity for abstract reasoning and language in anything more than rudimentary forms....................So my rather more idealist stance is that the human being is able to transcend the biological. — Wayfarer

Trying to keep the post relevant to Kant through understanding the word "transcendence".

Why cannot abstract reasoning and language be explained within biology?

If abstract reasoning and language could be explained within biology, then it would not be necessary for any transcendence of the biological.

Biological processes are capable of many surprising things. Taking one example at random, the ScienceDaily has a 2009 article Scientists Show Bacteria Can 'Learn' And Plan Ahead

Bacteria can anticipate a future event and prepare for it, according to new research at the Weizmann Institute of Science. In a paper that appeared June 17 in Nature, Prof. Yitzhak Pilpel, doctoral student Amir Mitchell and research associate Dr. Orna Dahan of the Institute's Molecular Genetics Department, together with Prof. Martin Kupiec and Gal Romano of Tel Aviv University, examined microorganisms living in environments that change in predictable ways. Their findings show that these microorganisms' genetic networks are hard-wired to 'foresee' what comes next in the sequence of events and begin responding to the new state of affairs before its onset.

Other examples can be found showing simple mechanical structures looking surprisingly life-like.



The word "transcendental " has different senses

From the Merriam Webster dictionary, "transcend" as a transitive verb can mean
1a to rise above or go beyond the limits of
1b to triumph over the negative or restrictive aspects of
1c to be prior to, beyond, and above (the universe or material existence)
2 to outstrip or outdo in some attribute, quality, or power.

There seem to be two distinct uses. The first is that of being explainable, as in "Great leaders are expected to transcend the limitations of politics". The second is that of being unexplainable, as in "certain laws of human nature seem to transcend historical periods and hold true for all times and all places".

But the fact that something is unexplainable today does not mean that it will be forever unexplainable.

Today we may say that "language transcends biology" in the second sense of the word as unexplainable, but it may well be the case that in the future as we gain more knowledge we may say that "language transcends biology" in the first sense as explainable.

Similarly for Kant in 1781, he may be using the word "a priori" as "transcendental" in the second sense as unexplainable, but today, over 200 years later, with our knowledge of Innatism and Enactivism, we can use the word "a priori" as "transcendental" in the first sense as explainable.

Another case of linguistic aberration? — Corvus

Not really, it depends what the word "direct" is referring to.

The Phenomenological Direct Realist would say that they have both a direct perception (causally direct) and direct cognition of the postbox as it really is in a mind-independent world.

The Semantic Direct Realist would say that they have an indirect perception (causally indirect) but a direct cognition of the postbox as it really is in a mind-independent world.

The Indirect Realist would say that they have an indirect perception (causally indirect) and indirect cognition of the postbox as it really is in a mind-independent world.

I believe that Kant would say that he has both an indirect perception (causally indirect) and indirect cognition of the postbox as it really is in a mind-independent world, ie, the same as what an Indirect Realist would say.

I think your belief in the mind-independent nature of existence is innate. — Wayfarer

Yes, as with Chomsky, I believe in a certain amount of Innatism. As the Wikipedia article on Innatism writes:
In the philosophy of mind, innatism is the view that the mind is born with already-formed ideas, knowledge, and beliefs. The opposing doctrine, that the mind is a tabula rasa (blank slate) at birth and all knowledge is gained from experience and the senses, is called empiricism.

Such Innatism can be combined with the principle of Enactivism. As the Wikipedia article on Enactivism writes:
Enactivism is a position in cognitive science that argues that cognition arises through a dynamic interaction between an acting organism and its environment.

For me, Kant's references to the "a priori" are explained by what we know today as Innatism, a natural consequence of life's 3.7 billion years of evolution in a dynamic dance with the world of which it is a part.

As Bryan Magee wrote: "the inborn realism which arises from the original disposition of the intellect"

Yeah, whenever I read "Indirect X", I always get curious, "Indirect" from what, how and why? — Corvus

In this case, the prefix "in" means "not". Therefore, some people are direct realists, and some people are not-direct realists.

The problem is then knowing what "direct" refers to. Does it mean causally direct or cognitively direct?

The first of these is that if all the characteristics we are able to ascribe to phenomena are subject-dependent then there can be no object in any sense that we are capable of attaching to the word without the existence of a subject. Bryan Magee.

The earth, say, as it was before there was life, is a field of empirical enquiry in which we have come to know a great deal; its reality is no more being denied than is the reality of perceived objects in the same room. Bryan Magee. — Wayfarer

Neutral Monism denies the reality of the Earth

From the position of Neutral Monism, there is only one substance, elementary particles and elementary forces in space-time, and there is only one aspect of it, neither mental nor material, but rather, in some sense, neutral between the two.

From the position of Nominalism, universals and abstracts don't exist in the world.

From the position of Conceptualism, universals and abstracts don't exist outside the mind's perception of them.

From the position of Reductionism, complex systems are no more than the sum of their parts. For example, biological life can be explained in terms of its physical processes and the temperature of a gas can be explained by the average kinetic energy of its molecules in motion.

As regards the question, did the Earth exist before there was life, it depends on what one means by the Earth. In one sense it did exist and in another sense it absolutely didn't exist.

If the Earth is a concept in the human mind, amongst many other concepts such as apples, tables, angst, love, pain, fear, mountains, governments, then prior to the human mind, before there was life, then of course it didn't exist. How can a concept which depends for its existence on the human mind exist before there were human minds to have the concept.

If the Earth is a concept in the human mind, then from the viewpoint of today, I can say that "the Earth existed before there were human minds", as the Earth I am referring to is not something that existed prior to the human mind, but the Earth as it exists as a concept in my mind at this present moment in time.

If the Earth is not a concept in the human mind but exists independently of any human mind, then there are serious problems as to what exactly judges in the absence of any human mind when something is the Earth and when it is no longer the Earth, as the Earth is in a continual process of change. For example, the Earth formed about 4.54 billion years ago by accretion from the solar nebula, a mass of dust and gas left over from the formation of the Sun. What decided that 5 billion years ago the mass of dust and gas was not the Earth, but 4 billion years ago the mass of dust and gas was now the Earth. A human mind could make the judgement, but Bryan Magee is not saying that, he is inferring that in the absence of any human mind, something has judged at what moment in time a mass of gas and dust becomes the Earth.

I agree that if all the characteristics that we are able to ascribe to phenomena are subject dependent then there can be no object in any sense. I agree that if the subject is the human mind and the object is the Earth, if there is no human mind then there can be no Earth. But this ignores Neutral Monism, where if there is no subject, the human mind, there can still be an object, elementary particles and elementary forces existing in space and time.

Only thing about "Indirect Realism" is that, "Indirect" sounds a bit vague. Would it not be better called something like "Representational Realism"? Because appearance and sense-data represent the contents in the mind. — Corvus

Possibly. The Wikipedia article on Direct and Indirect Realism does give alternate names:
In the philosophy of perception and philosophy of mind, direct or naïve realism, as opposed to indirect or representational realism, are differing models that describe the nature of conscious experiences.

The problem is, is it possible to describe a theory about which millions of words have been written using just two words.

I think of "Indirect Realism" as a name rather than a description, as the Taj Mahal is the name of and not a description of a building. Similarly I think of "Transcendental Idealism" as a name rather than a description.

I challenge that claim. I see Kant as a qualified realist - he describes himself as being at the same time, an empirical realist but also a transcendental idealist, and says that these are not in conflict. I know that there are deflationary readings of Kant, which attempt to show that he was, at heart, a realist, but then, there are many different interpretations on this point. The key factor in all this is the Kant denies that space and time have mind-independent existence. — Wayfarer

It come down to definition.

Some believe that the world exists in a mind, such as Berkeley, and others believe that there is also a world that exists outside the mind, such as Kant.

I agree with the SEP article on Idealism that within modern philosophy there are sometimes taken to be two fundamental conceptions of idealism:
1) something mental (the mind, spirit, reason, will) is the ultimate foundation of all reality, or even exhaustive of reality, and
2) although the existence of something independent of the mind is conceded, everything that we can know about this mind-independent “reality” is held to be so permeated by the creative, formative, or constructive activities of the mind (of some kind or other) that all claims to knowledge must be considered, in some sense, to be a form of self-knowledge.

I agree with the SEP article of Realism that there are two general aspects to realism:
There are two general aspects to realism, illustrated by looking at realism about the everyday world of macroscopic objects and their properties. First, there is a claim about existence. Tables, rocks, the moon, and so on, all exist, as do the following facts: the table’s being square, the rock’s being made of granite, and the moon’s being spherical and yellow. The second aspect of realism about the everyday world of macroscopic objects and their properties concerns independence. The fact that the moon exists and is spherical is independent of anything anyone happens to say or think about the matter.

I agree that Kant is described as both an Empirical Realist and Transcendental Idealist. However, Kant did propose that the phrase "Transcendental Idealism" could be improved.
In the Introduction to the CPR by Paul Guyer and Allen Wood:
Specifically, he differentiated his position from Berkeleian idealism by arguing that he denied the real existence of space and time and the spatiotemporal properties of objects, but not the real existence of objects themselves distinct from our representations, and for this reason he proposed renaming his transcendental idealism with the more informative name of "formal" or "critical idealism," making it clear that his idealism concerned the form but not the existence of external objects.

The key factor that Kant denied that space and time have a mind-independent existence is similar to my position as an Indirect Realist in my belief that the colour red has no existence outside of my mind. If I see a red postbox, it is not the case that the postbox is red, but rather the postbox appears red in my mind. The fact that when I taste an apple as sweet does not mean that sweetness exists in a mind-independent world. The fact that I see a spatial relation between two objects, in that I see an apple above a table, does not mean that spatial relations ontologically exist in a mind-independent world.

To see something in the world does not of necessity mean that it exists in the world, as in bent sticks.
===============================================================================

I think that you need the concept of the thing in itself to stand in for what you understand as what is real, independently of any mind, as the mind-dependence of things is too radical a position for you to accept. — Wayfarer

I feel I went to sleep in Dublin and have been teletransported to Königsberg.

Concepts in the mind must refer to something. They cannot be empty terms.

We say that the concept in the mind of a thing-in-itself refers to a real thing existing in a mind-independent world.

But the problem is, things-in-themselves in a mind-independent world are by definition mind-independent.

But the concept in the mind of a thing-in-itself must refer to something. What do you think the concept in the mind of a thing-in-itself refers to?

Hence framing Kant as a Phenomenologist needs close investigation — Corvus

To my understanding, Kant cannot be described as a Phenomenologist, as phenomena are only one part of his "Transcendental Idealism".

As the IEP article Phenomenology writes:

Phenomenology, then, is the study of things as they appear (phenomena).

Kant endorsed “transcendental idealism,” distinguishing between phenomena (things as they appear) and noumena (things as they are in themselves)

On Kant’s view, the I is purely formal, playing a role in structuring experience but not itself given in experience. On Husserl’s view, the I plays this structuring role, but is also given in inner experience.
===============================================================================

Would it be the ground for making Kant an Indirect Realist? — Corvus

:up: I would argue that Kant is in today's terms definitely an "Indirect Realist".

Do the Phenomenalists claim to know the real world perceived as the appearance? Or is it unknown existence? — Corvus

It's a complicated topic that I only vaguely comprehend, and can only understand using simple analogies. For example, if I put my hand on a radiator and feel intense heat, my moving my hand has been determined by my immediate experience, not by any consideration about the cause of my experience. At a later time, I can contemplate about possible reasons why the radiator was hot, but thoughts about the cause didn't determine my action, my experience determined my action .

Husserl seems central to Phenomenology. From SEP Phenomenology:
Still, the discipline of phenomenology, its roots tracing back through the centuries, came to full flower in Husserl.

Husserl's concept of "bracketing" seems important to Husserl. From Wikipedia Bracketing (phenomenology)
The preliminary step in the philosophical movement of phenomenology is describing an act of suspending judgment about the natural world to instead focus on analysis of experience.

As Husserl built on Kant's Transcendental Idealism, I imagine the Phenomenologist immediately experiences Appearance and only transcendently knows the world outside of experience. From Wikipedia Bracketing (phenomenology)
Edmund Husserl, building on Kant’s ideas, first proposed bracketing in 1913, to help better understand another’s phenomena.
===============================================================================

What would be the differences between Appearance of the postbox, and Sense-Data of the postbox? — Corvus

Speaking as an Indirect Realist, I would say that Appearance and Sense-data are synonyms, where both are figures of speech, and are two different ways of looking at the same thing.

This would be in opposition to the Direct Realist, who would say neither exist, in that when looking at a postbox we are looking directly at the postbox and not at some intermediary thing. IE, we are directly looking at the postbox, not a representation of the postbox.

Would I be right in saying that you see Kant as regarding the ding an sich as the real object, from which apparent objects are merely derivative? — Wayfarer

Was Kant a Realist?

Kant was not an Idealist but a Realist, in that Things-in-Themselves in the world are the grounds for the Appearances in our minds.

Although we cannot cognize about the Thing-in-Itself, we can still think about them.
CPR Preface Bxxvi "even if we cannot cognize these same objects as things in themselves, we at least must be able to think them as things in themselves.

GJ Mattey in his lecture notes wrote about Kant's acceptance of the existence of an external world.

In Remarks II and III of Part One, Kant confronted the issue directly, and dangerously. Genuine idealists hold that the only real beings are thinking beings, everything else being representations in the thinking beings. Kant, on the other hand, denies this thesis. Appearances are appearances of things in themselves, so that what we call bodies exist not merely as representations (as stressed in the Fourth Paralogism), but as things in themselves. "I grant by all means that there are bodies without us, that is, things which, though quite unknown to us as to what they are in themselves, we yet know by the representations which their influence on our sensibility procures us. These representations we call 'bodies,' a term signifying merely the appearance of the thing which is unknown to us, but not therefore less actual. Can this be termed idealism? It is the very contrary" (Ak. 290). A vital feature of this claim is that the unknown thing is said to "influence" our sensibility, and as such, we can only postulate it as a cause. But then it seems that we are back to the original problem, i.e., the dubiousness of causal inference. Kant might respond that what is dubious in causal inference is not that there is a cause, but what the cause is. And he has admitted that the cause of our representations of bodies is unknown. "Neither the transcendental object which underlies outer appearances nor that which underlies inner intuition, is in itself either matter or a thinking being, but a ground (to us unknown) of the appearances which supply to us the empirical concept of the former as well as of the latter mode of existence" (A379-80). Unfortunately, Kant had also claimed that the concept of causality can be justifiably applied only to objects of experience, as the condition of rule-governed change of the states of empirical objects. Thus his appeal to the unknown cause of our representations falls victim to his limitation of the use of our understanding to experience.
===============================================================================

Does he say in so many words that the ding an sich is the cause of the appearance? — Wayfarer

Does Kant's Category of Causation apply to Things-in-Themselves?

Kant writes in Prolegomena to any Future Metaphysics 1783 that the category of cause and effect can be applied to things-in-themselves.
"And we indeed, rightly considering objects of sense as mere appearances, confess thereby that they are based upon a thing in itself, though we know not this thing as it is in itself, but only know its appearances, viz., the way in which our senses are affected by this unknown something."

It is true that the Categories in general apply only to Appearances, the Phenomena, but it can be argued that the Category of Cause is a special case and does also apply transcendentally to the Thing-in-Itself, the Noumena.

Claude Piche in his article Kant and the Problem of Affection makes this point, where he concludes:

The contribution of this paper is that I have tried to make sense of the thing in itself as the "transcendental ground" of appearances. Rather than simply consider the thing in itself as a "necessary" concept, as in Allison's view, my purpose is to demonstrate that for Kant the actuality of the thing in itself as the cause of appearances must be necessarily posited. The thing in itself is not merely an epistemic condition that we must "think"; it is a critical-metaphysical assumption that must be made, one that becomes part of philosophical knowledge. The critical philosopher knows that there is something beyond the appearances. But in this case, there is nothing dogmatic about such an assumption since it is required by the transcendental explanation of our knowledge itself. I have tried to argue that there is a legitimate philosophical use of the category of causality which links affection to the thing in itself, as long as the constraints implied by such a concept (Le., heterogeneity and indeterminateness of the correlate) are respected, even at this higher level of argumentation. The normative constraints of such a transcendental discourse cannot be empirical, nor can they be the product of pure invention. The self-referentiality of philosophy, as it has been sketched here, entails that the transcendental use of a category is permissible strictly in view of the explanation of the only way in which experience is rendered possible.
===============================================================================

Kant's philosophy implies that while there is something that exists independently of our perception (the thing-in-itself), our understanding of it is always mediated by our cognitive faculties. — Wayfarer

How can we talk about Things-in-Themselves if we are unable to cognize about Things-in-Themselves?

Kant wrote in the Preface that even though we cannot cognize about a Thing-in-itself , we can still think about possible Things-in-Themselves as long as we are able to justify our reasoning:
Bxxvi "even if we cannot cognize these same objects as things in themselves, we at least must be able to think them as things in themselves.

We can't talk about something that we don't even know exists, meaning that when we do talk about something either we believe it exists, believe it could possibly exist or know it exists.

As we do talk about things-in-themselves, this means that we either believe they exist, believe they could possibly exist or know they exist.

How can we believe that something exists, believe that it could possibly exist or know it exists without first cognizing about the subject of our belief or knowing?

Phenomenology is not directly concerned with what is or is not real as it is a proposed method of exploring experience. — I like sushi

Yes, that's true, for the Phenomenologist, the real world is external to our consciousness, according to the SEP article on Phenomenology:
In its root meaning, then, phenomenology is the study of phenomena: literally, appearances as opposed to reality.
Realistic phenomenology studies the structure of consciousness and intentionality, assuming it occurs in a real world that is largely external to consciousness and not somehow brought into being by consciousness.

On the other hand, the only world the phenomenologist knows is the world as it exists within these experiences, and these experiences are real to them. Could one perhaps say that the world as they experience it is real to them?

So then which world is real, Appearance or Thing-in-itself? Or are they the same world? — Corvus

However, Appearance has hint of being the mental representation. Appearance is not the world either, is it? — Corvus

Suppose someone sees a red postbox.

If they were a Phenomenalist, the Appearance is the real world.

If they were an Indirect Realist, they would say that although the postbox appears red, the postbox as a Thing-in-Itself is not necessarily red. For the Indirect Realist, although the Appearance is real, the real world is the unknown Thing-in-Itself that is the cause of the Appearance.

If they were a Direct Realist, they would say that because the postbox appears red then the postbox as a Thing-in-Itself is red. For the Direct Realist, as the Appearance is directly of the thing-in-itself, not only is the real world the thing-in-itself, but they have direct knowledge of the real world through its Appearance.

As far as I know, Kant's position can be described as that of an Indirect Realist.

I see Mary in the office, being professional, managing the office, arriving on time, smartly dressed and courteous to her workmates. I see Mary on the weekend, drinking in the bar, late leaving the house, dressed sloppily, shouting at the noisy neighbour and forgetting to buy soap at the supermarket. Which is the "real" Mary?

Wittgenstein wrote in PI 404 "Though someone else sees who is in pain from the groaning" . There is the public and objective behaviour of pain, the groaning, the Appearance, describable in words and there is the private and subjective feeling of pain, the Thing-in-Itself, indescribable in words. Which is the "real" pain, the Appearance of pain or pain as a Thing-in-itself?

An Astronomer looking into the distant sky sees galaxy HD1. The Astronomer is only seeing the Appearance of HD1, a few photons of light entering their telescope that left the galaxy 13.5 billion years ago, yet HD1 as a Thing-in-Itself has the mass of possibly 1.5 trillion solar masses. Which is the "real" HD1, the Appearance of HD1 in the Astronomer's telescope or HD1 as a Thing-in-itself?

In the 1960's and 70's was developed the "dual aspect" view of the relationship between Appearance and Thing-in-Itself. In numerous passages Kant describes the appearance and thing-in-itself distinction, not as a distinction between two different objects, but as two ways of considering the same object.

Kant wrote in the Preface that even though we cannot cognize about a Thing-in-itself , we can still think about possible Things-in-Themselves as long as we are able to justify our reasoning:
Bxxvi "even if we cannot cognize these same objects as things in themselves, we at least must be able to think them as things in themselves.

Some believe in an Epistemological dual aspect, in that we can consider objects as objects of appearance or we can consider objects as things in-themselves. Others believe in a Metaphysical dual aspect, in that objects of appearance are bearers of empirical relational properties, while objects as things-in-themselves are bearers of non-empirical intrinsic properties.

The Merriam Webster Dictionary list several meanings of the word "real" as an adjective, so which meaning of the word" real" is the real one?

(SEP - Kant's Transcendental Idealism)

You can say what you like, but depending on the ground of the determinations by which you say anything at all, re: how you understand things in general, and in particular from transcendental philosophy, you cannot say “the window was broken by a thing-in-itself”. — Mww

It is interesting question why on seeing a broken window I instinctively believe that something broke it, even though I may never know exactly what. Why do I have a primitive belief that if something happens there must have been a reason? Why does my belief in cause and effect seem innate?

It is a matter of debate whether the Kant's Category of Causality applies only to Appearances or also to Things-in-Themselves.

First, Kant was not a Phenomenologist, in that he believed there are objects outside the mind and second, he made use of the Principle of Sufficient Reason, where any change in time of an object of experience must conform to causal law.

Kant does say in A20/B34 that an object may be understood in two ways, as an Appearance and as a Thing-in-Itself.
The effect of an object on the capacity for representation, insofar as we are affected by it, is sensation." That intuition which is related to the object through sensation is called empirical. The undetermined object of an empirical intuition is called appearance.

In numerous passages, Kant does describe the Appearance and Thing-in-Itself distinction, but it can be argued not as a distinction between two different objects but as two ways of considering the same object, inferring what is called the Dual Aspect View.

The Dual Aspect view of Kant, developed in the 1960's and 70's attempted to overcome the Phenomenalist problem with Affection, and argued that the Phenomenologists had mistakenly assumed that appearance and things-in-themselves are ontologically distinct kinds of objects.

Kant wrote in the Preface that the same object can be considered as it appears to us or as it is in itself.
The same objects can be considered from two different sides, on the one side as objects of the senses and the understanding for experience, and on the other side as objects that are merely thought at most for isolated reason striving beyond the bounds of experience. (Bxviii–Bxix, note) the reservation must well be noted that even if we cannot cognize these same objects as things in themselves, we are at least able to think of them as things in themselves. (Bxxvi)

There are passages in the Fourth Paralogism where the Thing-in-Itself is declared the cause of Appearance
A380 The transcendental object that grounds both outer appearances and inner intuition is neither matter nor a thinking being in itself, but rather an unknown ground of those appearances that supply us with our empirical concepts of the former as well as the latter.

Kant also writes in Prolegomena to any Future Metaphysics 1783 that the category of cause and effect can be applied to things-in-themselves.
"And we indeed, rightly considering objects of sense as mere appearances, confess thereby that they are based upon a thing in itself, though we know not this thing as it is in itself, but only know its appearances, viz., the way in which our senses are affected by this unknown something."

Kant can be argued to be avoiding an ontological distinction between Appearance and Things-in-Themselves in favour of a distinction between the form of an Appearance, in other words its phenomenology, and the content of an Appearance, in other words things-in-themselves. The consequence is that it is not the case that Causality can only be applied to Appearance, but can in fact be applied to the content of the Appearance as it affects the form of the Appearance. Kant claims that only the form of experience is mind-dependent, not its matter, as the matter of experience depends on a source outside the mind. Kant may be read as arguing that the sensory content is affected by the matter of mind-independent objects, things-in-themselves, while the form of experience is determined by the mind alone. Kant makes the point that the sensory content is not generated by the mind, but is generated by affection with mind-independent objects, things-in-themselves, which are then structured by the categories.
Kant wrote: the Critique posits this ground of the matter of sensory representations not once again in things, as objects of the senses, but in something super-sensible, which grounds the latter, and of which we can have no cognition. (Discovery, Ak. 8:205)

As Kant was not a phenomenologist, and believed in both Appearance and Things-in-Themselves, where the Things-in-Themselves are the cause of the Appearance, the Category of Causality cannot apply just to the Appearance but must also apply to the cause of that Appearance, ie the Things-in-Themselves.

Wikipedia - Thing-in-Itself
Claude Pichet - Kant and the problem of affection
https://hume.ucdavis.edu/kant/CAUSE.HTM
YouTube - Kant's Categories - Daniel Bonevac

Here is the summary from ChatGPT on the problems of OLP. — Corvus

:up:

I think someone on this forum mentioned some time ago that they chose to distinguish between ‘real’ and ‘exist’ in terms that a unicorn can ‘exist’ but it cannot be ‘real’. The ‘thing-in-itself’ is neither of these as it is just an empty term that can neither be conjured by imagination nor experienced in reality. — I like sushi

If I see a broken window, as nothing happens without a reason, I know that at a prior time something broke it. I may never know what broke the window, in that it could have been a bird or a stone, but I know something did. I can name this unknown thing "something", enabling me to say "the window was broken by something".

It is also the case that this word "something" can be replaced by other words such as "thing-in-itself" without affecting the function of the sentence. So I can equally say "the window was broken by a thing-in-itself".

So what is this "something" or "thing-in-itself" referring to? In language are many words that don't refer to one particular concrete thing but do refer to abstract concepts. For example, in the expression "I can imagine a house", the word "house" is not referring to one particular concrete thing but rather is referring to the abstract concept of a house. Similarly, in the expression "I can imagine a thing-in-itself", the word "thing-in-itself" is not referring to one particular concrete thing but rather is referring to the abstract concept of a thing-in-itself.

I can imagine a thing-in-itself as I can imagine a house, not as one particular concrete thing but as an abstract concept. As a "house" isn't an empty term then neither is a "thing-in-itself" an empty term.

Would you not agree that figures of speech can be confusing, and is illogical? — Corvus

Yes, figures of speech can be confusing, but as figures of speech are an inherent part of language, figures of speech and the confusion they bring is unavoidable.

For example, when you wrote in your OP: To see what other folks think about this issue, I have opened this thread asking what is your reason to believe in the world, when you are not perceiving it?, the phrases "to see what other folks think" and "I have opened this thread" are definitely figures of speech. I would argue that words such as "world" and "perceiving" are also figures of speech.

As regards language being logical, there have been attempts to found language on logic, but seemingly unsuccessful. For example, Frege. As the Britannica article on Frege's Revolution notes about Frege, Frege attacked Locke's idea that ideas exist independently of words. Frege proposed that the meaning of a sentence, the thought it expresses, is a function of the structure, the syntax, of the sentence. The thought it expresses is not determined by the speaker or hearer of the sentence, but is determined by the logical structure of the sentence, where an individual word has meaning because of its context within the sentence of which it is a part.

However, Frege's logical language is contrasted with ordinary language, which as the Britannica article on the Ideal Language wrote about an ideal language:
In analytic philosophy, a language that is precise, free of ambiguity, and clear in structure, on the model of symbolic logic, as contrasted with ordinary language, which is vague, misleading, and sometimes contradictory.

The fact that a word such as "world" has created so much discussion and disagreement is because it is a figure of speech, and as a figure of speech is open to multiple interpretations.

But could you not say that your perception is caused by your sense-data? i.e. the sense perception of the external world? — Corvus

I know that at this moment in time I perceive a world in my mind, and assuming that nothing happens without a reason, there must have been a prior cause for such a perception.

This prior cause was either i) external to my mind or ii) internal to my mind. But because there is no information within an effect as to its cause, it is logically impossible to know whether the cause of my perception of a world in my mind was either external or internal to my mind.

If the prior cause of my perception of a world in my mind was external to my mind, then we can say that the information from whatever was external to my mind passed through my sense-data, where sense-data can be thought of as an interface between my mind and whatever is external to my mind.

However, perception, world, internal, external and sense-data should all be thought of as figures of speech rather than literally existing, and as figures of speech only exist in the mind as concepts.

If the prior cause of my perception of a world in my mind was external to my mind, though this is logically impossible to know, then yes, there would be a causal chain going back in time of which sense-data would be one link in the chain.

I have opened this thread asking what is your reason to believe in the world, when you are not receiving it? — Corvus

My perception of a world in my mind is the effect of some prior cause, on the assumption that my perception hasn't spontaneously caused itself.

This prior cause was either i) external to my mind or ii) internal to my mind.

As there is no information within an effect as to its cause, it is therefore logically impossible to know the cause of an effect just from the effect itself. This means that it is also logically impossible to know whether the cause of my perception of a world in my mind was either external or internal to my mind.

As it is logically impossible to know whether anything exists external to my mind, it also follows that it is logically impossible to know whether or not anything that may exist external to my mind continues to exist when I stop perceiving a world in my mind.

If I come to you with a piece of paper with evidence saying that what is written on the paper outlines some ‘object’ beyond of sensory appreciation, and this paper has nothing written only it, would you accept this as evidence of some object wholly beyond our ken. — I like sushi

The piece of paper you are shown is evidence that the piece of paper exists.

As the piece of paper hasn't existed since the beginning of time, we know that something created it, even though we may not know what created it. The piece of paper is evidence that something existed at a prior time even though what that something was may be unknown to us.

IE, the piece of paper is evidence of something that existed at a prior time that may well be wholly beyond our ken.

@Antony Nickles @Ludwig V

I appreciate your considered replies, and because of them have learnt a lot about the philosophy of Austin over the past few weeks, but am leaving the Thread for the reason I gave in response to @Banno.

Thank you for that, Russell, since it shows so clearly that you are not paying attention, but making shite up. — Banno

I don't need playground bullying, so I'm leaving the Thread.

What the dictionary says is not (to coin a phrase) definitive. — Ludwig V

Yes, as Barbossa said about the Pirate's Code, they are more guidelines than actual rules. But in the absence of rules, guidelines are better than nothing.

The two most important ones, in my book are "to perceive by the eye: to perceive the meaning or importance of". I think the latter is metaphorical. — Ludwig V

Perhaps "to perceive by the eye" is also metaphorical, in that is it the eye that is doing the perceiving or the person who is using their eye.

Ayer maintains that "see" has two meanings, both of which are covered by "perceive by the eye". — Ludwig V

Is this likely? There were dictionaries during his lifetime.

Austin is specifically not claiming we see directly or indirectly (bottom of p. 3), but that the whole thing is made up, including the picture of “material objects”, metaphysics’ “reality”, etc. — Antony Nickles

Austin is conflating sense and reference

Austin is inferring that both the Indirect Realist who argues that there is a difference between sense-data and material object and the Direct Realist who argues there are is no sense-data but only material object hold positions that are spurious:
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 antithesis. The question, do we perceive material things or sense-data, no doubt looks very simple-too simple-but is entirely misleading ( cp. Thales' similarly vast and oversimple question, what the world is made of). One of the most important points to grasp is that these two terms, 'sense-data' and 'material things', live by taking in each other's washing-what is spurious is not one term of the pair, but the antithesis itself. There is no one kind of thing that we 'perceive' but many different kinds.

Austin describes Ayer's position, which is as an Indirect Realist:
The general doctrine, generally stated, goes like this: we never see or otherwise perceive (or 'sense'), or anyhow we never directly perceive or sense, material objects (or material things), but only sense-data (or our own ideas, impressions, sensa, sense-perceptions, percepts, &c.).

Consider the dichotomies i) far and near and ii) sense-data and material objects.

Expressions such as "far and near" have a sense and a reference. As regards reference, far could refer to something at a distance 100m and near could refer to something at a distance of 1m. As the distances 100m and 1m are not opposites, as a reference, far and near are neither mutually exclusive nor contradictory. However, as regards sense, far and near are mutually exclusive and contradictory.

Similarly, the expression "sense-data and material object" also has a sense and a reference. As regards sense, they are mutually exclusive and contradictory. As regards reference, sense-data could refer to an effect such as photons entering the eye, and material object could refer to a cause, such as photons being emitted by a material object, and as a reference are not mutually exclusive nor contradictory.

The Indirect Realist is considering the pair sense-data and material object in two distinct ways. In one way as sense, which is a linguistic dichotomy, and in another way as reference, which is not a metaphysical dichotomy.

However, Austin's argument is flawed, as he infers that because there is no metaphysical dichotomy, then there cannot be a linguistic dichotomy, which is an invalid argument.

It depends what you mean by "understand". — Ludwig V

On the one hand, I would start by looking at the Merriam Webster definition of "understand"

On the other hand, an animal such as a dog has a non-verbal instinctive understanding not to put their paw into an open fire

IE sentient beings can have both a verbal understanding of the word "understanding" and a non-verbal understanding of the concept understanding.
===============================================================================

So far as I know, no-one suggests that photons are the sense-data for the eyes. That would be an entirely different matter. For example, it would be very strange to say that what we see is photons. — Ludwig V

Figures of speech are inherently strange

I agree, it is a very strange thing for the Indirect Realist to say what we see is sense-data. But then it is also a very strange thing for the Direct Realist to say that what we see are material objects.

But such is the strange nature of a language that is fundamentally metaphorical, where the figure of speech is foundational to language. For example, as discussed by George Lakoff and Mark Johnson in their book Metaphors We Live By.

As an Indirect Realist, I can say "I see sense-data" meaning "I perceive by the eye sense-data" and I can say "I see a material object" meaning "I imagine the possibility of a material object".

However, the figure of speech is foundational to language, meaning that the expressions "I perceive by the eye", "sense-data", "I imagine the possibility" and "material object" are all figures of speech and therefore not to be taken literally.

As "I see your inner pain" is a figure of speech, "I see sense-data" is also a figure of speech, and neither are intended literally.
===============================================================================

Now we need to work out what it means to buy something indirectly. — Ludwig V

How about:
I bought the table directly from the manufacturer through their outlet shop.
I bought the table indirectly from the manufacturer through their internet site
===============================================================================

So how does this work in the case of "directly see the car that ran over my foot"? — Ludwig V

How about:
I directly saw the car that ran over my foot.
I indirectly saw the car that ran over my foot through a reflection in a shop window
===============================================================================

OLP is not about definitions................... asking ourselves in just what circumstances we would say which, and why. Consider, then: (1) He looks guilty. (2) He appears guilty. (3) He seems guilty. — Antony Nickles

OLP couldn't exist without definitions

A definition is foundational to OLP.

We hear a scream outdoors and our dog enters the room. Consider a fourth possible expression "he x guilty". We have to decide which of the four words "looks", "appears", "seems" or "x" is the most appropriate within the given context. Our task is impossible if we don't know what "x" means, and to discover what "x" means we have to go to the dictionary for a definition.

Without the words "looks", "appears", "seems" or "x" having previously been defined, it would be impossible for us to determine which was the correct word to use in the given context.
===============================================================================

So it’s not that philosophy should “use” ordinary usage. It looks at ordinary usages in individual cases to inform philosophical claims because what we are interested in about a subject — Antony Nickles

The expression "Ordinary Language Philosopher" is ambiguous.

Austin thought that the best way to analyse philosophical problems was by analysing language. He thought that most philosophical problems are caused by the ambiguous use of language, and many philosophical problems would disappear if language was used more rigorously.

I agree that Austin's first step in undertaking philosophy was to analyse language as it is ordinary used by the competent speaker.

However, the expression "Ordinary Language Philosopher" is ambiguous.

Does it mean either 1) the OLP uses ordinary language when analysing ordinary language or 2) the OLP analyses ordinary language but doesn't use ordinary language?

and the point about that particular case is that no clear meaning has been assigned to "direct". — Ludwig V

Though the Merriam Webster dictionary does narrow down the definition of "direct" when used as an adverb to:
a) from point to point without deviation, by the shortest way - flew direct to Miami
b) from the source without interruption or diversion - the writer must take his material direct from life
c) without an intervening agency - buy direct from the manufacturer

When I look into the night sky and see the planet Mars, I am able to see Mars because of the photons of light entering my eye. These photons had previously travelled the 380m km through empty space after leaving the planet.

So when I say "I directly see Mars", as there is no information within these photons that their source was Mars, I am using the word "directly" in a figurative rather than literal sense.
===============================================================================

But if we try to understand that non-verbal reality we find ourselves unable to do so. — Ludwig V

Until whilst walking through a town someone driving in a car runs over my foot.
===============================================================================

A microscope will discover many things, but never a star. — Ludwig V

Yes, stalemate. Ayer's method pre-determines what he will discover and Austin's method pre-determines what he will discover.

This is perhaps why on the Forum for a Thread to come to an agreed conclusion is probably as rare as hen's teeth.

As Austin wrote:
In these lectures I am going to discuss some current doctrines (perhaps, by now, not so current as they once were) about sense-perception. We shall not, I fear, get so far as to decide about the truth or falsity of these doctrines; but in fact that is a question that really can't be decided, since it turns out that they all bite off more than they can chew.

Perhaps the moral is that one doctrine cannot criticise another doctrine based on its own particular foundational beliefs.

As the sense-data theory cannot show that OLP is invalid, OLP cannot show that the sense-data theory is invalid.

Well OLP is not a movement, nor a belief-system, it’s a method, but Austin is not abandoning either truth, as I discuss here nor is OLP giving up on the essence of things, as I argued in the last paragraph here. — Antony Nickles

The following is my understanding, but am ready to be persuaded otherwise.

Is Austin really an OLP?

I see a bent stick and know that my perception could have been caused by either i) seeing a bent stick or ii) seeing a straight stick in water. I see an ellipse and know that my perception could have been caused by either i) seeing an ellipse head on or ii) seeing a circle at an angle.

The Merriam Webster dictionary definition of the word "see" includes i) to perceive by the eye and ii) to imagine the possibility.

Ayer, as an Indirect Realist, is using the word "see" in both ways. He is seeing as in perceiving by the eye a bent stick and is also seeing as in imagining the possible cause as either i) a straight stick in water or ii) a bent stick.

In Ayer's terms, seeing as in perceiving by the eye an effect can be called sense-data and seeing as in imagining the possibility can be called the material object.

But Austin in Sense and Sensibilia is saying that Ayer is wrong, in that we don't see sense-data but do see the material object.

My only conclusion from this is that Austin is saying that using the word "see" as to perceive by the eye is invalid and using the word "see" to imagine the possibility is valid. But this position is against the meaning of the word "see" as set out in the Merriam Webster dictionary as ordinarily used by competent speakers of the language .

As OLP is the position that philosophy should be carried out using words as ordinarily used by competent speakers of the language, and Austin appears not to be following the tenets of OLP, as shown by the Merriam Webster Dictionary example, this suggests that in fact he cannot be described as an OLP.

Well OLP is not a movement, nor a belief-system, it’s a method, — Antony Nickles

The particular method used to obtain an object will pre-determine any object discovered

According to the IEP article Ordinary Language Philosophy -
Ordinary Language philosophy, sometimes referred to as ‘Oxford’ philosophy, is a kind of ‘linguistic’ philosophy. Linguistic philosophy may be characterized as the view that a focus on language is key to both the content and method proper to the discipline of philosophy as a whole (and so is distinct from the Philosophy of Language).

According to the Merriam Webster Dictionary, "method" can typically mean a procedure or process for attaining an object: such as a way, technique, or process of or for doing something.

OLP is clearly not a just a method of philosophy, as its chosen method of focusing on language will inevitable pre-determine any conclusions it reaches.

OLP is the belief-system that philosophical enquiry must focus on language.

A method of philosophy that focuses on language will necessarily come to different conclusions to a method of philosophy that doesn't focus on language.
===============================================================================

but Austin is not abandoning either truth, as I discuss here nor is OLP giving up on the essence of things, as I argued in the last paragraph here. — Antony Nickles

As you said "because the truth will “turn on… the circumstances in which it is uttered.”(p.111)"

True. If I said to someone "you are truly hot", this would have several possible meanings dependent upon context. Some literal and some figurative.

As you said "But Austin also shows how “reality”...............is a manufactured idea".

True. The concept of "reality" is manufactured within language.

OLP proposes to try to reach an unbiased take on each example — Antony Nickles

OLP cannot be unbiased about sense-data as the Christian cannot be unbiased about Atheism

OLP is a movement that believes philosophy must lose its grand metaphysical aspirations in asking such questions "what is truth" and "what is essence" in favour of a philosophy based on ordinary language used by competent speakers of that language. Philosophers should instead ask what does it mean to say that "is it true that it is raining in Paris" and "this perfume has a fine essence".

Any movement that believes that philosophy must lose its grand metaphysical aspirations is obviously biased against philosophers who have grand metaphysical aspirations.
===============================================================================

I am not talking about the “metaphysical problem” (whether it exists in or out of language, or can or can not be discussed), but the metaphysician’s use of words (knowledge, intent, real, direct, etc.) in comparison to our ordinary use of those words, which reveals how and why metaphysics wants to remove context and generalize only one type of case. — Antony Nickles

The metaphysician interested in the sense-data problem removes linguistic context because the metaphysical question "do I directly see sense-data or do I directly see an object" is independent of language

Yes, OLP believed that philosophy should lose its grand metaphysical aspirations and stop trying to understand words in terms of the universal and abstract, such as "what is truth", but concentrate on understanding words as they are used in ordinary language by any competent speaker, such as "is it true that it is raining in Paris".

This approach follows from Frege's Context Principle, In his book The Foundations of Arithmetic he changed the metaphysical question "what are numbers" into the linguistic question what does it mean to say "the number of horses is four"

The Indirect Realist is asking the metaphysical question "do I directly see sense-data or do I directly see an object". Metaphysical because such a question cannot be answered by the sensations alone but only from reasoning about the sensations.

It is true that the metaphysician interested in sense-data wants to remove context, as such a metaphysical question is independent of language, and context is an inherent part of language.

It is not true that the metaphysician interested in sense-data is wanting to generalize only one type of case. They are interested in the specific and particular case "do I directly see sense-data or do I directly see an object".

(Wikipedia - The Foundations of Arithmetic)

Moore...................Wittgenstein..................but the lessons from these examples are not a substitute for the foundation that metaphysics wants — Antony Nickles

True, but they are a foundation for what Ordinary Language Philosophy wants
===============================================================================

OLP is examining what anyone would say in a particular situation, in order to find unbiased philosophical data, not as proof of a position — Antony Nickles

OLP as any method cannot avoid but being biased

OLP is a method, and as with any method, is only able to discover those things that it is structurally capable of discovering. By that I mean, if given a problem, whether scientific or philosophical, the method I choose in order to solve that problem determines any solution that I may discover. For example, I may want to discover the nature of reality, and my chosen method is visual observation. However, the reality I discover will be only be that part of reality accessible to vision. I will be missing that part of reality only accessible to touch, hearing, etc .

As no method is unbiased, using OLP as a method to investigate the philosophical nature of reality will inevitably come up with a biased answer, an answer biased by the very method being used. OLP is one method amongst many, including Analytic, Logical Positivism, Phenomenology, Scepticism, Common Sense, Verifications, Continental, Aristotelianism, etc, where each will give a different answer biased by the inherent nature of the method itself.

OLP by its very nature of having a specific method can only result in biased conclusions. It is inevitable.
===============================================================================

Austin is also looking at the metaphysical use of words (attempting to give them as much sense as he can — Antony Nickles

I would think that the metaphysical use of words is a logical impossibility.

Words can be used to describe Ayer's metaphysical problem with sense-data. For example, I can say: "when looking at a red postbox, for the Direct Realist the postbox is literally red and for the Indirect Realist the postbox appears red, not that the postbox is literally red".

Ayer's metaphysical problem with sense-data is independent of language and would still happen in a world without language, in that language is not an aspect of the metaphysical situation. When a person looks at a red postbox, is the postbox literally red, or does the person have a private mental sensation of the colour red?

On the one hand, the metaphysical problem of sense-data is independent of language, yet on the other hand, the metaphysical problem of sense-data can be discussed within language. Wittgenstein gave a solution to this conundrum in Philosophical Investigations 293 using the beetle in the box analogy, where we can talk about pain yet cannot describe pain. The private sensation of pain, the beetle in the box, drops out of consideration within the language game. The word "pain" in language is not describing an unknown cause, pain, but is describing the known effect of an unknown cause, ie, pain behaviour.

Similarly, Austin might talk about "the metaphysics of do we directly see sense-data or directly see the object", but this expression is not describing an unknown cause, whether sense-data or an object, but is describing the known effect of an unknown cause, ie, seeing something.

But if the argument is that God exists and that argument is absurd, until there is another argument, there is no basis for asserting that God exists. No? — Ludwig V

True, in the absence of a good argument that God exists people fall back on faith.

So you believe both positions and that no argument can settle the issue? Basically on the grounds that any argument must be from one position or another and that it cannot therefore address the issue. H'm. That would need some explaining. — Ludwig V

Exactly my problem with Austin's Sense and Sensibilia, in that from the position of linguistics he does take a position on the metaphysics of sense-data.

Ordinary Language Philosophy has nothing to do with common sense or with the ordinary man, as I tried to explain here (and elsewhere as referenced in that post), it is a philosophical method, not a position. — Antony Nickles

I would have thought that Ordinary Language Philosophy (OLP) is associated with GE Moore's common sense and the later Wittgenstein's ordinary language of the ordinary person-in-the-street.

OLP doesn't reduce philosophy to ordinary words, but proposes that philosophy can better be undertaken using ordinary words. OLP does not reduce philosophy to the person-in-the-street, but suggests that philosophy should be understood by the person-in-the-street. OLP looks at the ordinary use of words, what words mean within the context they are being used in.

OLP looks at words such as direct and indirect and points out it is not possible to make the simple statement that direct and indirect have opposite meanings. Not only does direct have several different meanings dependent upon context but also indirect has several different meanings dependent upon context.

OLP points out that problems arise when ordinary words having commonly agreed meanings are given unusual new meanings by philosophers in their attempt to solve philosophical problems, thereby creating more philosophical problems than they solve

Because of the nature of language, in that the meaning of a word depends on its context within the whole, and between words are family resemblances, OLP tend to be anti-essentialist, meaning that their philosophy is more about relationships between truth and reality rather than based on an absolute truth or reality.

However, Ernest Gellner in Words and Things 1959 made the valid point that as language derives from the communities within which we live, as these communities are ever-changing and unstable, philosophical ideas expressed within our language will also inevitably be ever-changing and unstable.

(Wikipedia - Ordinary Language Philosophy)

OK. But the argument in question here is the argument that we never perceive reality, only sense-data. — Ludwig V

Linguistics and metaphysics are two very different fields of enquiry.

Austin's Sense and Sensibilia is written from the viewpoint of an Ordinary Language Philosopher.

I can understand Austin, as an Ordinary Language Philosopher, making the point that sense-data is not a necessary part of linguistics, which I agree with.

However, I don't agree that he then continues to argue, still as an Ordinary Language Philosopher, that sense-data is not a valid metaphysical position.

The metaphysics of sense-data, which is outside of language, cannot be critiqued by an Ordinary Language Philosopher from a position that reality is established by language.

The difficulty is that arguments about metaphysics have to be expressed in language. If the (attempts to express) metaphysical argument result in self-contradiction or absurdity, they cannot be correct. — Ludwig V

True, the argument for sense-data theory can only be expressed in language.

However, if the argument results in self-contradiction or absurdity, it is possible that it is the argument that is self-contradictory or absurd, not the topic of the argument.
===============================================================================

I don't believe in God, yet I can tell you what the arguments for and against are. What's the problem? — Ludwig V

Your arguments for the existence of God haven't persuaded you of the existence of God, so they cannot be very persuasive.

I am perceiving by the eye a three-dimensional form — Ludwig V

Before I can comment, it depends what you mean.

Do you mean either i) at one moment in time when looking at an object I am perceiving by the eye a three-dimensional form or ii) at several moments in time when walking around an object I am perceiving by the eye a three-dimensional form.
===============================================================================

I wouldn't say he ignores metaphorical meanings for "apple". He explicitly draws attention to one kind of relevant metaphor in the passage you quote. He also draws attention to the difference between that metaphorical use and the literal use. — Ludwig V

When looking at a radar screen the technician would ordinarily say "I see the enemy ships", inferring that they see the enemy ships directly rather than indirectly. This suggests that the expression "I see the enemy ships" is not to be taken literally but metaphorically.

However, there is more to it than that, in that within Austin's Ordinary Language Philosophy the words within the metaphor are to be taken literally rather than figuratively. This is in the same way as described by Donald Davidson in his article What Metaphors Mean.

In Ordinary Language Philosophy, the expression "I see the enemy ships", although classified as a metaphor, is intended to be taken literally, in the same way that a Direct Realist when saying "I see a red postbox" means not only that they see a red postbox but that the postbox is literally red.

This leads into the debate between Direct Realists who argue they directly see an object in the world and the indirect Realist who argue that they directly see the sense-data from an object in the world.
===============================================================================

As it happens, in the example you cite, "I" am perceiving by the eye (in future, I will write "see" instead of this cumbersome form) two dimensional forms which I know give me information about the three-dimensional world. I can't see any important metaphysical questions from this. — Ludwig V

The relevance is linguistic, in that the word "see" has several meanings, including "to perceive by the eye" and "to imagine a possibility".
===============================================================================

It is perfectly possible for someone who believes in God to formulate an argument for the existence of God that deserves to be taken seriously. — Ludwig V

True, but it would be more difficult for someone who believes in God to formulate an argument for the non-existence of God.
===============================================================================

Ordinary Language Philosophy is a method of evaluation and he is using it to evaluate Ayer's argument and he comes to the conclusion that the argument is invalid. — Ludwig V

An Ordinary Language Philosophy as a philosophical methodology would be agnostic about Ayer's metaphysical sense-data theory, but Austin's Sense and Sensibilia is clearly more than a philosophical methodology as it concludes that Ayer's metaphysical sense-data theory is wrong.

Austin and Ayer hold two independent positions. Austin, as the name Ordinary Language Philosophy suggests, that of linguistics, and Ayer that of metaphysics. The problems of linguistics are different to and independent of the problems of metaphysics.

Ordinary Language Philosophy is about the meaning of an expression such as " I see an object in the world", whereas sense-data theory is about whether we see an object in the world directly or do we see the sense-data from that object directly. These are two very different things and shouldn't be conflated.

I believe that sense-data are metaphysically true, and I also believe that sense-data is irrelevant to linguistics. For linguistics to try to prove or disprove the metaphysical theory of sense-data is like asking a person to describe something they don't know about.

Linguistics and metaphysics are two independent fields of study, and the existence of one neither proves not disproves the existence of the other.
===============================================================================

You seem to be saying that the sense-data theory is irrelevant. — Ludwig V

I agree that from Austin's Ordinary Language point of view the sense-data theory is irrelevant.

If you know that there's another side to the apple, you know that you are looking at a three-dimensional object, so you are not seeing in two dimensions. — Ludwig V

In what sense are you using the word "see".

From the Merriam-Webster dictionary, the word "see" can have several meanings, including "to perceive by the eye" and "to imagine a possibility".

You say that because you know that you are looking at a three-dimensional object then you are not seeing in two-dimensions.

By this, do you mean either i) you are perceiving by the eye a three-dimensional form or ii) you are imagining a three-dimensional form?

The problem with Austin

The problem with Austin is that he is taking his Ordinary Language philosophy too far, even further than the Ordinary Man would take it.

For example, in the expression "I see an apple", Austin's approach is to ignore any possible metaphorical meaning for its so-called "ordinary" usage, thereby turning a blind eye to the range of possible meanings as laid out in the Merriam-Webster dictionary.

As he wrote: For reasons not very obscure, we always prefer in practice what might be called the cash-value expression to the 'indirect' metaphor. If I were to report that I see enemy ships indirectly, I should merely provoke the question what exactly I mean.' I mean that I can see these blips on the radar screen'-'Well, why didn't you say so then?'

For Austin, "I see an apple" is all one needs to know. However, for Ayer, it is an important metaphysical question when looking at an apple whether I am perceiving by the eye a three-dimensional form or I am imagining the possibility of a three-dimensional form.

I thought that helping each other to understand Austin's text was the point of the thread. — Ludwig V

That's why I included my understanding of Austin's position regarding sense-data in page 5 of this thread, which has neither been supported nor opposed.

Though, as an aside, as a Christian author could write an article evaluating Atheism and unsurprisingly find it wanting, Austin, as a believer in Ordinary Language Philosophy, has written an article evaluating sense-data theory and has unsurprisingly find it wanting. From Austin's Ordinary Language point of view, I may well agree that sense-data is irrelevant, but that does mean that the sense-data theory is irrelevant.

Which use is literal and which is metaphorical? — Ludwig V

Clearly, the first is meant literally and the second metaphorically.

If "see" means literally "to perceive by the eye", when standing in front of an object such as an apple I can only see the front of it. If "see" means metaphorically "to imagine a possibility", when standing in front of an object such as an apple, I can also see the back of it.

Is there anyone who thinks that we can literally "see the future", "see into her mind", "see the solution", "see what you mean", "see the end of time", "see the other side of the Universe", "see atoms", "see evolution happening", "see Caesar's dilemma" or "see gravitational waves".

But how does this help us understand this topic? — Ludwig V

I'm not here to help you understand Austin's Sense and Sensibilia, I'm here to specifically respond to @Banno by pointing out that different meanings of the word" see" shouldn't be conflated.

Though, as an aside, as a Christian author could write an article evaluating Atheism and unsurprisingly find it wanting, Austin, as a believer in Ordinary Language Philosophy, has written an article evaluating sense-data theory and has unsurprisingly find it wanting. From Austin's Ordinary Language point of view, I may well agree that sense-data is irrelevant, but that does mean that the sense-data theory is irrelevant.

There was a recent, very odd discussion in the Case for Transcendental Idealism thread - ↪Gregory, ↪Corvus and ↪RussellA apparently insisting that they see only in two dimensions, only imagining the third... I couldn't make sense of it. — Banno

As Oscar Wide said:"There is only one thing in life worse than being talked about, and that is not being talked about.”

It depends what you mean by "see".

According to the Merriam Webster Dictionary, two possible meanings of "see" are i) to perceive by the eye and ii) to imagine as a possibility.

Therefore, both the following statements are true: "I can only see in two dimensions" and "I can also see in three dimensions", dependent on whether the word "see" is being used literally or metaphorically.

Metaphors are a legitimate part of language. In What Metaphors Mean, Donald Davidson wrote:"Metaphor is a legitimate device not only in literature but in science, philosophy, and the law; it is effective in praise and abuse, prayer and promotion, description and prescription."

Yes, as Davidson points out, language is full of inherent ambiguities, when he wrote: "Another brand of ambiguity may appear to offer a better suggestion. Sometimes a word will, in a single context, bear two meanings where we are meant to remember and to use both."

Keep reading CPR. The answer is in it. — Corvus

Of its 785 pages, can you narrow it down a bit?