• Paine
    3.1k
    Kant wrote his massive tome to show this is wrong.
    — Jamal

    Yes, I agree.
    Corvus

    It is confusing to have you acknowledge that Kant argued against your argument immediately after you claim that he supported it.
  • AmadeusD
    3.7k
    LOL.

    From what I've seen the main argument in the last two pages has been that Banno thinks if there are things we don't currently know, then Antirealism can't hold.

    Well... *sigh*. That is.. not reasonable.

    There are plenty of things we may never come into contact with. That doesn't make them unknowable. Unknown and unknowable are simply not the same.

    Now, I presume I've missed something major. But I don't see it anywhere. Someone want to help me out there?
  • Paine
    3.1k
    From what I've seen the main argument in the last two pages has been that Banno thinks if there are things we don't currently know, then Antirealism can't hold.AmadeusD

    It is difficult to follow your argument since you base it upon an interpretation of what an interlocuter has said rather than engage in the debate proffered.
  • Metaphysician Undercover
    14.5k
    Well... *sigh*. That is.. not reasonable.AmadeusD

    There are many ways to show how the argument is not reasonable, I provided one. The argument requires a very narrow perspective to work. It works for Banno because he adopts that narrow perspective and refuses to talk to anyone who will not take it. It's like saying the argument requires these assumptions, and if you do not accept these assumptions, I will not discuss it with you. What's the point?
  • I like sushi
    5.2k
    With a simple smattering of charity you could just have offered that they are maybe trying to say that phenomenon is all we have via sensibility?

    @Corvus I think that is all that is being said?
  • AmadeusD
    3.7k
    This didn't help. LOL
  • Ludwig V
    2.3k
    If this isn’t the case, then there must be other things that are not seen, even by an anti-realist. Because there might be more than one anti-realist.Punshhh
    Well, yes. But can an anti-realist know that there is more than one anti-realist? I think not, and that's why I think that the only consistent form of idealism is solipsism.

    ...... antirealism, which is the epistemic position that if something is true, then it is knowable.Banno
    That seems entirely reasonable. I guess the problems must be in the fine print.

    There cannot be any unknown truths if every truth is knowable.Banno
    But what is the force of "cannot"? Does it mean that we don't have the technology? Or does it mean that we have to develop a new approach (elliptical orbits instead of circular ones?

    If we are to hold that we do not know everything, then there are things we cannot know.Banno
    Well, I can see that perhaps we cannot know all truths. But it does not follow that there are any truths that we cannot know.

    If we do not know everything, then antirealism is not an option.Banno
    I think the distinctions between known unknowns and unkowns is relevant here. lt seems to me that the former are not incompatible with anti-realism (or some forms of it). I may not know the tenth place in the expansion of pi (5), but I know that there's a method for finding it. But it also seems to me that the latter are. However, I don't see that anything prevents us from discovering at least some of them and developing new concepts in the process.

    That doesn't seem to me to be addressing Fitch, .....Banno
    Perhaps not. I don't really think I'm capable of demonstrating that it is wrong. On the contrary, I think it is right, provided the context is right. IEP - Dynamic Epistemic Logic has a helpful summary of the argument:-
    From ∃p (p ∧ ¬Kp) follows the truth of its instance (p ∧ ¬Kp) → ◊ K(p ∧ ¬Kp), and from that and p ∧ ¬Kp follows ◊ K(p ∧ ¬Kp). Whatever the interpretation of ◊, it results in having to evaluate K(p ∧ ¬Kp). But this is inconsistent for knowledge and belief.
    It is clearly true that I cannot know that p (is true) and that I do not know that p. In general, if the person who knows (K) is the same as the person who asserts the starting-point, it is self-contradictory (Moore's paradox). But it is not contradictory if the person asserting the starting-point is different from the person who knows. There's no problem about me asserting (knowing) that p is true and someone else does not know it. I'm not sure what impact, if any, this has on realism/anti-realism.

    From what I've seen the main argument in the last two pages has been that Banno thinks if there are things we don't currently know, then Antirealism can't hold.AmadeusD
    I agree with you that it is not obvious that known unknowns threaten antirealism. But unknown unknowns do. The catch is that we don't, and can't, know what they are. We only know that there are such things because we have encountered some of them before.

    I'm not sure if it is relevant but @Banno doesn't assert merely that there are things that we don't currently know.
    It (sc. Fitch's paradox) begins with Up(p⊃◇Kp), which is not temporally dependent.Banno
    . l agree, though, that a move from "knowable" to "known" does seem to require tenses.
  • Corvus
    4.6k
    I think that is all that is being said?I like sushi

    My reality is strictly constructed with my perception, sensation and imagination and belief. What I don't sense and perceive, I rely on my imagination and belief. There is no objectivity in there. Even my own perception and sensation can sometimes mislead me. There is no 100% guarantee that my perception and sensations are infallibly true. And what is more, what I perceive and sense is perhaps not even 0.0000000000001 percent of the world. How could I pretend to claim to know what the world is?

    Now this is not a solipsism like some have been misled on the point. It is the critical nature of our perception, mind and reality under the philosophical analysis.
  • Corvus
    4.6k
    I think that is all that is being said?I like sushi

    Some say Kant was a phenomenologist, quite understandably so.
  • Paine
    3.1k

    Fair enough, I should have minded my own business.

    Now this is not a solipsism like some have been misled on the point.Corvus

    There are different varieties of solipsism? How can they be compared to each other? That would seem to cancel the isolation you are reporting.
  • Ludwig V
    2.3k
    There is no objectivity in there. Even my own perception and sensation can sometimes mislead me.Corvus
    It is true that our perception and sensation can sometimes mislead us. But "sometimes" means that sometimes they do not mislead us. That looks like objectivity to me.

    There is no 100% guarantee that my perception and sensations are infallibly true.Corvus
    No, there's no guarantee. But that doesn't make them subjective.
  • AmadeusD
    3.7k
    But unknown unknowns do. The catch is that we don't, and can't, know what they are. We only know that there are such things because we have encountered some of them before.Ludwig V

    Yes, I understand that obstacle. I suppose my problem with thinking this has any effect, whatsoever, on these conceptual analyses is that it is wholly fact-specific and empirical. We may never, ever, in our entire existence come across some substance which exists 60,000 light years away and further. That is, on it's face, and unknowable unknown. If the idea is that for antirealism to hold, everything knowable must be in concept, in hand, then I see only two realistic responses:

    1. That's nonsense, and obviously so; or
    2. Is what's actually being said is something more like "you can't claim something is unknowable conceptually" which seems wrong in it's own way but I can see the argument.

    My big problem with any issue with "unknowns" is that they are simply unknown. We can't comment on them, no matter what system we ascribe to. I'm happy to presume there are plenty of things humans will never (and, physically/practically/empirically) can never know. I'm not seeing hte issue. If i've missed it (i presume I have) please help lol.
  • Corvus
    4.6k
    There are different varieties of solipsism? How can they be compared to each other? That would seem to cancel the isolation you are reportingPaine

    I know you exist by the language we share to communicate, art and music we share, and posts you write. But that's it. Beyond that, I don't know anything about your mind, and its content. Solipsism doesn't take into account on these points. They say that nothing else exists apart from their own mind, or some might even say, their mind doesn't exist either. That is solipsism.

    My point is that as long as we exist communicating and sharing on these cultural and linguistic activities, we can infer and postulate our existence and others. But beyond that, we are still in our own world. Even if I had a very intimate discussions on many topics or shared some daily life experience with someone, I would not claim I know their deep true inside feelings, thoughts and wills. At this point, we are not talking about someone's physical existence here, like Banno has been insisting to have.
  • Corvus
    4.6k
    It is true that our perception and sensation can sometimes mislead us. But "sometimes" means that sometimes they do not mislead us. That looks like objectivity to me.Ludwig V
    I am not sure if perception can be objective in any sense. In what sense what I am seeing X is same as you are?

    No, there's no guarantee. But that doesn't make them subjective.Ludwig V
    Nothing makes perception and sensation subjective. Aren't they subjective experience by nature?
  • Paine
    3.1k
    Even if I had a very intimate discussions on many topics or shared some daily life experience with someone, I would not claim I know their deep true inside feelings, thoughts and wills.Corvus

    It sounds like what you are calling "solipsism" is what other people refer to as single individuals.
  • Ludwig V
    2.3k
    I am not sure if perception can be objective in any sense.Corvus
    Nothing makes perception and sensation subjective.Corvus
    For most people, I think, if something can be true or can be false, it is objective. There's no truth or falsity to something subjective.

    In what sense what I am seeing X is same as you are?Corvus
    Do you mean if I am seeing a bus and you are seeing a bus, in what sense are we seeing the same object? In one sense, if we are seeing different buses, we are seeing two objects of the same kind. If we are both seeing the same bus, we are seeing the same object. Does that help?

    Even if I had a very intimate discussions on many topics or shared some daily life experience with someone, I would not claim I know their deep true inside feelings, thoughts and wills.Corvus
    But if you know that they have some deep true inside feelings etc. then it must be possible, even if it is difficult, to know what they are.

    I'm not seeing hte issue. If i've missed it (i presume I have) please help lol.AmadeusD
    That's most likely because you are not wearing the right spectacles. Here's my take on it:-
    In analytic philosophy, anti-realism is the position that the truth of a statement rests on its demonstrability through internal logic mechanisms, such as the context principle or intuitionistic logic, in direct opposition to the realist notion that the truth of a statement rests on its correspondence to an external, independent reality. In anti-realism, this external reality is hypothetical and is not assumed. — Wikipedia - Antirealism
    This account rests on the the application of a metaphor to language - "external" and "internal". Realism asserts what antirealism denies - that there are things "outside" language and most language is "made true" by that reality. Antirealism asserts that truth and falsity are just a matter of internal coherence among the descriptions of language.

    Sometimes that seems to me to make perfect sense; sometimes I cannot get my head round it.
    That's one thing that makes the debate difficult. The strongest argument in favour of anti-realism is that there is no way to identify the non-linguistic, language-independent world without using language. The business about unknowns rests on the idea that if language is not complete, in the sense that there are facts that cannot be expressed in it, then there must be a distinction between language and the world it describes.

    So the hope is that by identifying "gaps" in language, we'll open a door into that world. The biggest problem in that project is that you can't identify something unless you know it.

    Does that help?
  • Corvus
    4.6k
    It sounds like what you are calling "solipsism" is what other people refer to as single individuals.Paine

    Solipsists will say, nothing exists apart from themselves no matter what. I am saying, we don't know something or somebody exists until we communicate, share feelings, art, music and ideas, and even meet in real life forming relationships.
  • Corvus
    4.6k
    For most people, I think, if something can be true or can be false, it is objective. There's no truth or falsity to something subjective.Ludwig V
    You seem to be confusing objectivity and truth. Objectivity is not necessarily truth. Subjectivity is not necessarily false.

    If we are both seeing the same bus, we are seeing the same object. Does that help?Ludwig V
    Nope. Not making sense at all. No two minds can see a bus exactly same. Even if you and your pal see a bus passing in front of you, your perception and his perception will be different in some way. You cannot stand on the exact position where he stands, and your eye sight wouldn't be same as his ...etc.
  • Ludwig V
    2.3k
    You seem to be confusing objectivity and truth. Objectivity is not necessarily truth. Subjectivity is not necessarily false.Corvus
    I didn't think I was, although we may have different definitions. For me, objectivity is true or false. Subjectivity is neither.

    Nope. Not making sense at all. No two minds can see a bus exactly same. Even if you and your pal see a bus passing in front of you, your perception and his perception will be different in some way. You cannot stand on the exact position where he stands, and your eye sight wouldn't be same as his ...etc.Corvus
    I didn't mean to say that your perception and my perception of the bus are exactly the same. For a start, one of them is yours and the other is mine. But that is merely numerical difference. I will stipulate that there will always be qualitative differences as well. But then, there will also be qualitative similarities too. Telling whether we are seeing the same bus is a matter of weighing those up. One example is that the one bus may well be at different points in our visual fields, which in any case can't be located in relation to each other. But we can use that information to identify where the bus is in public space. It we both locate our visual bus at the same point in our shared space, it is very likely to be the same bus. If we locate it in different points at the same time, it is almost certain to be two buses.
  • AmadeusD
    3.7k
    Not really. Again, my comments seem to run on from yours in a way that doesn't quite alter them.

    I think the biggest argument for antirealism is the actual facts of eyes, ears, noses and mouths (and skin, I guess). I do, however, think its possible I've not come across a name for the position I actually think its reasonable, because its not idealism as antirealism might suggest.
    I suggest antirealism about perception is roughly, unavoidable, but that antirealism as a metaphysical comment seems... tenuous as best, and seemingly ridiculous at worst. Maybe that clears up where I'm not understanding the issues in the previous comments.
  • Banno
    29.4k
    My apologies, I dropped this thread.

    . l agree, though, that a move from "knowable" to "known" does seem to require tenses.Ludwig V

    I don't see why.

    We can write "Kp" for "we know p", and "◇Kp" for "we might know p", and "~Kp" for "we don't know p" and "~◇Kp" for "we can't know p", none of which are tensed.
  • Ludwig V
    2.3k
    We can write "Kp" for "we know p", and "◇Kp" for "we might know p", and "~Kp" for "we don't know p" and "~◇Kp" for "we can't know p", none of which are tensed.Banno
    W can write "Kp" for whatever we like. Once we have interpreted it, however, (I think that's the right word), there are consequences.

    "we know p", is compatible (awkwardly) with "we might know p". But it is incompatible with "we don't know p" and "we can't know p".
    "we might know p" compatible with "we know p" and "we don't know p"; it is incompatible with "we can't know p",

    In other words, we can interpret "Kp" however we like, but that does not mean we can substitute any interpretation for any other. "We know that p" and "We might know that p" are not inter-substitutable.

    In addition, we have the issue of tensed or tenseless. This is complicated and doubly complicated in this context, because we have two verbs involved. But I'm stuck on "it is raining" does not follow from "It might be raining".

    I might well be confused about what tensed and untensed truths.

    I think the biggest argument for antirealism is the actual facts of eyes, ears, noses and mouths (and skin, I guess). I do, however, think its possible I've not come across a name for the position I actually think its reasonable, because its not idealism as antirealism might suggest.
    I suggest antirealism about perception is roughly, unavoidable, but that antirealism as a metaphysical comment seems... tenuous as best, and seemingly ridiculous at worst. Maybe that clears up where I'm not understanding the issues in the previous comments.
    AmadeusD
    I agree with you that we're not all that far apart. There is a truth in anti-realism; where I disagree with it is the inflation of that truth into a Grand Doctrine. In the case of perception, it is inescapable true that what we know about the world around us comes to us from our senses.
    But it is what the anti-realist (idealist) makes of this mundane fact that bothers me.
    The point of the discussion in that post is the idea that our perceptions (or language) are not self-contained but point beyond themselves to a mind-independent reality, which can be known by us. Which does not mean that we will ever know everything about everything, so that there are always some things that are not known.
  • AmadeusD
    3.7k
    But it is what the anti-realist (idealist) makes of this mundane fact that bothers me.Ludwig V

    Definitely. It's taken me a while to realise that its required to claim antirealism. It makes me very uncomfortable as I need to push back hard on the likes on Banno claiming that perception is direct.
  • Ludwig V
    2.3k
    Definitely. It's taken me a while to realise that its required to claim antirealism. It makes me very uncomfortable as I need to push back hard on the likes on Banno claiming that perception is direct.AmadeusD
    It seems to me that "direct" and "indirect" do not have a determinate application in the context of perception. So it's like "glass half full" and "glass half-empty". Which means one should not draw dramatic conclusions from either.
    But do we think that noise-cancelling headphones prevent us from hearing what's going on, or do we think that they enable us to hear what is going on?
    Do they distort reality? In one sense yes, in another sense no.
  • Banno
    29.4k
    W can write "Kp" for whatever we like. Once we have interpreted it, however, (I think that's the right word), there are consequences.

    "we know p", is compatible (awkwardly) with "we might know p". But it is incompatible with "we don't know p" and "we can't know p".
    "we might know p" compatible with "we know p" and "we don't know p"; it is incompatible with "we can't know p",

    In other words, we can interpret "Kp" however we like, but that does not mean we can substitute any interpretation for any other. "We know that p" and "We might know that p" are not inter-substitutable.

    In addition, we have the issue of tensed or tenseless. This is complicated and doubly complicated in this context, because we have two verbs involved. But I'm stuck on "it is raining" does not follow from "It might be raining".

    I might well be confused about what tensed and untensed truths.
    Ludwig V

    It's hard to see the relevance of much of this.

    Sure, we can't both know and not know the very same thing, and there are other similar permutations. "We know that p" and "We might know that p" are not inter-substitutable, but if we know p then it is possible that we know p.

    But this is not to do with tense.

    A realist will maintain that there are truths we do not know. An antirealist will maintain that every truth is possibly knowable. Fitch showed that if every truth is knowable, then every truth is known:
    (p → ◇Kp) ⇒ (p → Kp)

    That is, the antirealist cannot know that there are truths that cannot be known, without contradiction.

    Fitch shows that the antirealist cannot consistently maintain both that all truths are knowable and that there are any unknown truths; the antirealist must either accept omniscience, accept unknowable truths, or abandon the unrestricted knowability thesis.

    The view expressed by is pretty much that taken by Austin and by myself. , as I recall, was unable to follow the discussion. But the notion that all we know is found by perception if fraught with issues, peripheral to the question of what is real. It is a mistake to equate what we perceive with what is real.
  • AmadeusD
    3.7k
    It seems to me that "direct" and "indirect" do not have a determinate application in the context of perception.Ludwig V

    I suppose this, somewhat, rests on something Banno's type would say v something I would say:

    "When you look at a tree you see a tree".

    So much seems true. But I would say...

    "You factually do not see something "out there"". You see a tree, because that's what you see, we call a tree. Not because that's the same thing as what you cast your eyes upon. Something something ding en sich.

    You see something in your mind (or rather, generated by it). This is what I mean when I say indirect. It may be that there is no appreciable difference between the two - looking through a dark glass doesn't necessarily have you seeing something 'untrue'. But To suggest that we see the world undistorted seems to me something which can be set aside without much trouble. I've definitely had to drop aspects of these thoughts over the last year or so though, for the reason set out in the last two comments we made to each other: I don't think the world exists in the mind. I just don't see a problem with accepting there is a real world, and a world of perception - whatever their closeness in terms of identity.

    Do they distort reality? In one sense yes, in another sense no.Ludwig V

    I don't think 'distort' anything on the basic premises here. Closing ones eyes simply has us seeing the inside of our eyelids. Putting on noise-cancelling headphones simply has us hearing a restricted selection of the sounds we might otherwise hear. The same as going into one's car, to some degree. Its not the same as, for instance, an inability to see the frequency we call red. That's where the interesting stuff comes in, and where I've truly loved Banno's comments over the couple of years i've been here.
  • AmadeusD
    3.7k
    But the notion that all we know is found by perception if fraught with issues, peripheral to the question of what is real. It is a mistake to equate what we perceive with what is real.Banno

    Mate, I followed it. I didn't agree with you (or Austin, as it has since turned out).
    I agree, it's a mistake to equate what we perceive with what is real. I can't see the disagreement anymore.

    Fitch shows that the antirealist cannot consistently maintain both that all truths are knowable and that there are any unknown truths; the antirealist must either accept omniscience, accept unknowable truths, or abandon the unrestricted knowability thesis.Banno

    Are you able to explain in non-formal terms how this works?

    There doesn't seem to be any tension whatsoever between saying "there are things we can't know" and reality.
    I also don't understand how an antirealist is committed to saying all truths are knowable. That said, my understanding (or, probably more properly my ill-labeled position) is that an antirealist has to assume there are truths we don't know. So am more than happy to have it explained to me like I'm not following - cause this time i'm not lol. I don't know Fitch.
  • Banno
    29.4k
    I also don't understand how an antirealist is committed to saying all truths are knowable.AmadeusD
    SO what is it that you think a antirealist claims, say concerning the truth of facts in the physical world... perhaps concerning Russell's teapot, for example...

    Isn't it the case that they they will say something like that statements about the teapot do not have a truth value?
  • Sirius
    83
    A realist will maintain that there are truths we do not know. An antirealist will maintain that every truth is possibly knowable. Fitch showed that if every truth is knowable, then every truth is known:
    (p → ◇Kp) ⇒ (p → Kp)

    That is, the antirealist cannot know that there are truths that cannot be known, without contradiction.
    Banno

    "Every Truth is knowable" is subject independent. It does not presume the existence of knowers.

    "Every truth is known" is subject dependent since it presumes the existence of knowers.

    Note : I'm not making a tensed argument.

    So you can't claim both are represented by the same propositional form "kp" without justification.

    Does Fitch justify this? If not, then it's the worst case of question begging & the formal logic showpiece is nothing short of sophistry. Symbols can only take you so far, what matters more is semantics, epistemology & metaphysics at a deeper level.
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