• Indirect Realism and Direct Realism
    What would qualify as a constituent of experience? I'm drawing a blank.frank

    If property dualism is correct then qualia I suppose. Otherwise the constituents of experience just are whatever physical things mental phenomena are reducible to.
  • Indirect Realism and Direct Realism
    Distal objects do both, cause and become and/or 'act' as necessary elemental constituents of veridical experience.creativesoul

    Conscious experience occurs in the brain, distal objects exist outside the brain, therefore distal objects are not constituents of conscious experience.
  • Infinite Staircase Paradox
    As a regressive version of the argument, rather than me speeding up as I recite the numbers up to infinity let’s say that I slow down as I recite the numbers down from infinity.

    At the 60 second mark I said “0”, at the 30 second mark I said “1”, at the 15 second mark I said “2”, at the 7.5 second mark I said “3”, etc.

    Is it metaphysically possible for such a task to have been performed? No, because there is no first number that I could have started with.

    That we can sum an infinite series with terms that match the described (and implied) time intervals is a red herring.

    There is a far more fundamental, non-mathematical, logical impossibility with having counted down from infinity, and that very same fundamental, non-mathematical, logical impossibility applies with having counted up to infinity as well. You're being bewitched by maths if you think otherwise.
  • Infinite Staircase Paradox
    "The sequence of operations ends" means that "all operations in the sequence are performed".noAxioms

    The operations in the sequence occur one after the other, so all operations are performed only if some final operation is performed.

    The logic of consecutive tasks is different to the logic of concurrent tasks. Your account equivocates.

    If I never stop counting then … I never stop counting, and if I never stop counting then at no time have I ever counted every number.
  • Infinite Staircase Paradox


    That my dog is named "Bella" depends on me. That Bella exists and eats and sleeps does not depend on me.

    That this period of time is named "60 seconds" depends on us. That 60 seconds pass does not depend on us.

    You don't seem to understand how reference works.
  • Indirect Realism and Direct Realism
    Are you quoting naive realists, though?Luke

    Martin, Fish, and Allen are naive realists, I'm unsure if Nudds is or if he's just explaining naive realism, and the two SEP articles give overviews of the various positions without the authors commenting on their personal position.

    Some more quotes from two naive realists:

    Naïve realism is the view that the conscious character of experience in genuine cases of perception is constituted, at least in part, by non-representational perceptual relations between subjects and aspects of the mind-independent world. — French and Phillips 2020

    [N]aïve realists hold that ... [t]he conscious visual experience you have of the oak has that very tree as a literal part. — French and Phillips 2023
  • Infinite Staircase Paradox
    I think "reciting natural numbers" is a red herring, because it's perfectly clear that there are only finitely many atoms in the observable universe, and that we can't physically count all the natural numbers.fishfry

    Then rather than recite the natural numbers I recite the digits 0 - 9, or the colours of the rainbow, on repeat ad infinitum.

    It makes no sense to claim that my endless recitation can end, or that when it does end it doesn't end on one of the items being recited – let alone that it can end in finite time.

    So I treat supertasks as a reductio ad absurdum against the premise that time is infinitely divisible.
  • Infinite Staircase Paradox
    You can count the natural numbers by placing them into bijective correspondence with themselves. This is the standard meaning of counting in mathematics.fishfry

    This isn't the sense of "counting" I'm using. The sense I'm using is "the act of reciting numbers in ascending order". I say "1" then I say "2" then I say "3", etc.

    Say (in some hypothetical world, say current math or future physics) that we have a "sequence of actions" as you say, occurring at times 1/2, 3/4, 7/8, ... seconds.

    It's perfectly clear that 1 second can elapse. What on earth is the problem?
    fishfry

    P1. It takes me 30 seconds to recite the first natural number, 15 seconds to recite the second natural number, 7.5 seconds to recite the third natural number, and so on ad infinitum.

    P2. 30 + 15 + 7.5 + ... = 60

    C1. The sequence of operations1 described in P1 ends at 60 seconds without ending on some final natural number.

    But given that ad infinitum means "without end", claiming that the sequence of operations described in P1 ends is a contradiction, and claiming that it ends without ending on some final operation is a cop out, and even a contradiction. What else does "the sequence of operations ends" mean if not "the final operation in the sequence is performed"?

    So C1 is a contradiction. Therefore, as a proof by contradiction:

    C2. P1 or P2 is false.

    C3. P2 is necessarily true.

    C4. Therefore, P1 is necessarily false.

    And note that C4 doesn't entail that it is metaphysically impossible to recite the natural numbers ad infinitum; it only entails that it is metaphysically impossible to reduce the time between each recitation ad infinitum.

    1 A happens then (after some non-zero time) B happens then (after some non-zero time) C happens, etc.
  • Infinite Staircase Paradox
    I would invite you to read up on eternal inflation, a speculative cosmological theory that involves actual infinity. Yes it's speculative, but nobody is saying it's "metaphysically impossible" or "logically incoherent."fishfry

    Which has no bearing on what I'm arguing.
  • Infinite Staircase Paradox
    Here's a definition for you: "a supertask is a countably infinite sequence of operations that occur sequentially within a finite interval of time".

    The key parts are "sequence of operations" and "occur sequentially".

    As in, I do one thing, then I do another thing, then I do another thing, and so on ad infinitum. It is metaphysically impossible for this to end. If it ends then, by definition, it is not ad infinitum.
  • Infinite Staircase Paradox
    What's logically incoherent about infinite sets and transfinite ordinals?fishfry

    I'm not talking about infinite sets and transfinite ordinals. I'm talking about an infinite succession of acts. If you can't understand what supertasks actually are then this discussion can't continue.
  • Infinite Staircase Paradox
    I have not claimed otherwise.fishfry

    Those who argue that supertasks are possible claim otherwise, and it is them I am arguing against. You're the one who interjected.

    Nor does it disprove their metaphysical possibility. We just don't know at present.fishfry

    If I write the natural numbers in ascending order, one after the other, then it is metaphysically impossible for this to complete (let alone complete in finite time). This has nothing to do with what's physically possible and everything to do with logical coherency.
  • Infinite Staircase Paradox
    I gave you a mathematical model that puts your unsupported claims into context.fishfry

    And it doesn't address the issue.

    If I write the natural numbers in ascending order, one after the other, then this can never complete. To claim that it can complete if we just write them fast enough, but also that when it does complete it did not complete with me writing some final natural number, is just nonsense, and so supertasks are nonsense.

    That we can sum an infinite series just does not prove supertasks. It is clearly a fallacy to apply an infinite series to an infinite succession of acts.
  • Indirect Realism and Direct Realism
    To clarify, when you say that, according to naive realism, perceptions and perceived distal objects have the same physical constituents, do you take this to mean that perceptions and the perceived distal objects are identical?Luke

    You'll have to ask naive realists for specifics of what they mean; I can only quote what they say, which is that the relation between conscious experience and distal objects is more than just causal and is non-representational, using the term "constituent", which means "being a part".

    So, distal objects and their properties are literal component parts of conscious experience; in the same sense, perhaps, that the red paint is a literal component part of a painting.
  • Infinite Staircase Paradox
    I'm not the one advocating for supertasks, yet you keep arguing with me that they are impossible.fishfry

    No, I'm responding to you to explain that your reference to mathematical sets and mathematical limits does not address the issue with supertasks.

    Metaphysically impossible? Repeating a claim ad infinitum is neither evidence nor proof.fishfry

    I've provided arguments, and examples such as Thomson's lamp that shows why. And again, your reference to mathematical sets and mathematical limits does not rebut this.
  • Infinite Staircase Paradox
    You seem to assign some meaning to the word "event" that I don't understand.fishfry

    Would you prefer the term "act"? It is metaphysically impossible for an infinite succession of acts to complete.

    Have you even looked up supertasks? I don't know how you can confuse them with mathematical sets.
  • Infinite Staircase Paradox
    Do you deny infinite mathematical sets?fishfry

    No. An infinite set is not an infinite sequence of events. An infinite sequence of events would be counting every member of an infinite set. It is metaphysically impossible to finish counting them.

    Mathematically that's not true. The set {1, 2, 3, 4, ...} contains all the natural numbers, but there's no last number.fishfry

    That's not relevant to the claim I'm making.

    I'm saying that if I have finished counting the members of some set then some member must be the final member I counted.

    And besides, eternal inflation posits a temporally endless universe. It's speculative, but it's part of cosmology. Serious scientists work on the idea. So at least some scientists are willing to entertain the possibility of a physically instantiated infinity.fishfry

    I don't deny the possibility of something not ending. The issue is that supertasks entail that there is an end to infinity, which is nonsense.

    You keep repeating that, but you have no evidence or argument.fishfry

    Thomson's lamp, my box changing colour, the example of writing out each natural number, etc. I've offered plenty. Your attempt to rebut them by reference to mathematical limits fails to address the issue.
  • Infinite Staircase Paradox
    You're continuing to argue against a position I don't hold. Why are you doing this?fishfry

    Because I'm arguing against the possibility of a supertask. You're the one who interjected with talk of mathematical limits. I'm simply responding to explain that this doesn't address the concern I have with supertasks.

    I would, however, disagree with you that being inconsistent with known physics is the same as logical impossibility.fishfry

    I'm not saying that it's the same. I'm saying that as well as being a physical impossibility, supertasks are also a metaphysical impossibility.

    No physical law can allow for an infinite sequence of events to be completed. The very concept of an infinite sequence of events being completed leads to a contradiction. To claim that it is metaphysically possible to have finished writing out an infinite number of natural numbers but also that there is no final natural number that I wrote is to talk nonsense.

    If I finished writing out any number of natural numbers than there will be a final natural number and that natural number will be a finite number. This is a metaphysical necessity.
  • Indirect Realism and Direct Realism
    or else we’d be able to describe with some degree of accuracy what is actually going on in there.NOS4A2

    That's precisely what we are doing when we describe the pain we feel and the colours we see and the voices we hear when we dream or hallucinate.

    We might not be able to describe it in neurological terms (e.g. "such and such neurons are firing"), but then that's why I'm not entirely convinced by eliminative materialism and am open to property dualism.

    Even if you disagree with "perception" being the appropriate word to use for dreams and hallucinations, surely you have to accept that when we describe what's going on when we dream and hallucinate we're describing what's happening to/in us and not what's happening elsewhere in the world. The indirect realist simply argues that the same can be true of veridical experience because veridical experience, hallucinations, and dreams are all of a common kind – mental states with phenomenal character – that differ only in their cause (which is not to say that we can't also talk about their cause).
  • Indirect Realism and Direct Realism
    Experience is an act where the “distal objects” that we experience are acted upon in a certain way.NOS4A2

    This isn't what naive or indirect realists mean by "experience". They are referring to a particular kind of mental state with phenomenal character. These are, we now know, what occur when the appropriate areas of the brain are active, e.g. the visual and auditory cortexes.

    Take this:

    Disjunctivists and their opponents agree that veridical perceptions, illusions and hallucinations have something in common, in so far as they agree that such mental events should be grouped together as being perceptual experiences. They also agree that there are differences to be marked between them, hence the different labels for them. However, they disagree when it comes to specifying what these commonalities and differences consist in.

    ...

    Some disjunctivists claim that veridical perceptions have a phenomenal character that hallucinations cannot possess. For example, according to one version of naïve realism (what we might call ‘naïve realism about phenomenal character’), when one veridically perceives the world, the mind-independent items perceived, such as tables and trees and the properties they manifest to one when perceived, partly constitute one’s conscious experience, and hence determine its phenomenal character.

    ...

    The disjunctivist may insist that in a case of genuine perception, even if the objects of perception are distal causes of the subject’s experience, they are also figure non-causally as essential constituents of it. So the occurrence of the relevant brain processes won’t be sufficient to produce the kind of mental event involved in perception, unless further non-causal conditions necessary for the occurrence of that kind of mental effect also obtain.

    It's not clear to me that your account addresses anything of relevance. It simply uses the term "experience" to refer to a causal chain of events that connects some distal object to the body and then asserts (without really any meaning) that this connection is "direct". As it stands it's not something that either naive or indirect realists will disagree with; it simply redefines the words used.
  • Indirect Realism and Direct Realism
    They say only that it seems that wayLuke

    The first quote says that it seems to be that naive realism is correct; specifically "visual experiences seem to have the NR [Naïve Realist] property."

    It doesn't say that naive realism just claims that things seem to be a certain way. You're misreading the quote.

    or that our perceptions are shaped by those objects.Luke

    "... where this is understood in a constitutive, rather than merely a causal, sense."

    None of these quotes state or even suggest that the naive realism position is that their perceptions have the same physical constituents as the perceived object.Luke

    As well as the aforementioned, there's also "for the naive realist, insofar as experience and experiential character is constituted by a direct perceptual relation to aspects of the world, it is not constituted by the representation of such aspects of the world" and "what is fundamental to experience is something which itself cannot be explained in terms of representing the world: a primitive relation of presentation."

    Naive realists claim that it is the distal objects themselves, not mental representations, that are the constituents of experience.

    And I'll add another from The Disjunctive Theory of Perception:

    It follows that on a naïve realist view, the veridical perceptions and hallucinations in question have a different nature: the former have mind-independent objects as constituents, and the latter do not.
  • Indirect Realism and Direct Realism
    Your author of Semantic Direct Realism does not define naive realism (GDR or PDR) in terms of the physical constituents of percepts.Luke

    He says this:

    For the naïve realist, the realism and the directness is enshrined in the fact that the phenomena are intrinsic features of the object itself—they are how the object is in itself. The semantic direct realist is agnostic about how the phenomena relate to the object, but asserts that the experience constituted by the phenomena subjectively embodies information putatively about something external. This leaves open the possibility of raising questions about the relation of the phenomenal qualities of which we are aware in perception, and the object about which we are directly informed in perception: are they intrinsic to it as PDR claims, or are they more remote from it.

    And while I'm quoting him, I'll add this which gets to the heart of the matter:

    In Brewer’s case, however, it is the object per se with which one is directly acquainted (see (i) below.). On the one hand, this avoids the straightforward form of the illusion argument, as I have just stated it: on the other, it leaves the status and role in perception of the object’s sensible qualities still to be articulated. It also arouses the thought that the sense in which it is some external object which is the object of acquaintance is more logical than phenomenological: what would it be for the object to be phenomenologically present—in a sensory form—if none of its sensible properties are directly presented? As nowadays it is permitted to believe in cognitive phenomenology, one might assimilate the direct perception of objects without the direct perception of their sensible properties to that category. But that is precisely a form of semantic direct realism: the directness consists in something more akin to a proposition or a judgement. It is as if the theory is that in all perceptual-type experience there is an at least immanent judgement (conceptual or not) and that judgement has as its object something purportedly in the world. This is SDR and is, as we shall see, also something that a sense-datum theorist can accept.
  • Indirect Realism and Direct Realism
    Why can't naive realists simply hold the view that distal objects have the properties that they perceive them to have? I find your view that naive realists hold the view that their perceptions have the same physical constituents as the perceived object to be a strawman. Where did you get this idea from?Luke

    What’s so naïve about naïve realism?
    The second formulation is the constitutive claim, which says that it introspectively seems to one that the perceived mind-independent objects (and their features) are constituents of the experiential state. Nudds, for instance, argues that ‘visual experiences seem to have the NR [Naïve Realist] property’ (2009, p. 335), which he defines as ‘the property of having some mind-independent object or feature as a constituent’ (2009, p. 334), and, more explicitly, that ‘our experience […] seems to have mind-independent objects and features as constituents’ (2013, p. 271). Martin claims that ‘when one introspects one’s veridical perception one recognises that this is a situation in which some mind-independent object is present and is a constituent of the experiential episode’ (2004, p. 65).

    Naïve Realism
    Typically, today’s naïve realist will also claim that the conscious “phenomenal” character of that experience is shaped by the objects of perception and their features, where this is understood in a constitutive, rather than merely a causal, sense.

    The Problem of Perception
    For the naive realist, insofar as experience and experiential character is constituted by a direct perceptual relation to aspects of the world, it is not constituted by the representation of such aspects of the world. This is why many naive realists describe the relation at the heart of their view as a non-representational relation. This doesn’t mean that experiences must lack intentional content, but it means that (a) insofar as appeal is made to presentation to explain character, no appeal is made to intentional content for that purpose, and (b) what is fundamental to experience is something which itself cannot be explained in terms of representing the world: a primitive relation of presentation.

    A Naïve Realist Theory of Colour
    This book develops and defends the view that colours are mind-independent properties of things in the environment that are distinct from properties identified by the physical sciences.
  • Indirect Realism and Direct Realism
    I don't know of any physical/physiological difference.Luke

    So either there is some non-physical/non-physiological difference or there is no difference at all and the way you're trying to frame the issue is a confusion.

    Is it your position that our perceptions of real objects are mediated by mental representations or not?Luke

    This is my position. I've been very clear on this for the past 40-odd pages.
  • Indirect Realism and Direct Realism
    If mental representations do not mediate our perceptions of real objects, then our perceptions of real objects are not indirect, they are direct.Luke

    What is the physical/physiological difference between mental representations mediating perceptions of real objects and them not mediating perceptions of real objects?
  • Infinite Staircase Paradox
    I don't know what to tell you. 60 seconds can pass without anyone measuring it. If you can't accept this then we can't continue.
  • Indirect Realism and Direct Realism
    You know where your hand is at the moment. Do you know this indirectly? What could that mean? How is proprioception indirect?Banno

    It's what I said above:

    Indirect realists don't argue that percepts exist, that distal objects and their properties are not constituents of these percepts, and that perception is indirect, as if this latter claim is distinct from the other two. Rather, by "perception is indirect" they just mean that percepts exist and that distal objects and their properties are not constituents of these percepts – and the science of perception supports this.

    This is true even for proprioception (notwithstanding that "distal object" isn't quite the correct term to use when referring to one's hands), given that proprioceptive errors are possible.
  • Indirect Realism and Direct Realism


    I feel pain, pain is a percept, therefore I feel a percept. Nothing about this entails a homunculus. The schizophrenic hears voices and I see things when I dream. You are reading something into the grammar of "I experience percepts" that just isn't there and so inventing a strawman for indirect realism.

    Indirect realists don't argue that percepts exist, that distal objects and their properties are not constituents of these percepts, and that perception is indirect, as if this latter claim is distinct from the other two. Rather, by "perception is indirect" they just mean that percepts exist and that distal objects and their properties are not constituents of these percepts – and the science of perception supports this.

    Which is precisely why so-called "non-naive direct" realism is consistent with indirect realism. See Semantic Direct Realism.
  • Indirect Realism and Direct Realism
    The upshot is that indirect realism doesn't get the scientific stamp of approval its fans so desire.Banno

    This is what the science of perception shows:

    The process of perception begins with an object in the real world, known as the distal stimulus or distal object. By means of light, sound, or another physical process, the object stimulates the body's sensory organs. These sensory organs transform the input energy into neural activity—a process called transduction. This raw pattern of neural activity is called the proximal stimulus. These neural signals are then transmitted to the brain and processed. The resulting mental re-creation of the distal stimulus is the percept.

    To explain the process of perception, an example could be an ordinary shoe. The shoe itself is the distal stimulus. When light from the shoe enters a person's eye and stimulates the retina, that stimulation is the proximal stimulus. The image of the shoe reconstructed by the brain of the person is the percept. Another example could be a ringing telephone. The ringing of the phone is the distal stimulus. The sound stimulating a person's auditory receptors is the proximal stimulus. The brain's interpretation of this as the "ringing of a telephone" is the percept.

    This is indirect realism, not naive realism.

    Distal objects and their properties are not constituents of visual or auditory or olfactory experience.
  • Indirect Realism and Direct Realism
    But none of this is relevant to the point being made.

    Naive realists claim such things as this:

    The second formulation is the constitutive claim, which says that it introspectively seems to one that the perceived mind-independent objects (and their features) are constituents of the experiential state. Nudds, for instance, argues that ‘visual experiences seem to have the NR [Naïve Realist] property’ (2009, p. 335), which he defines as ‘the property of having some mind-independent object or feature as a constituent’ (2009, p. 334), and, more explicitly, that ‘our experience […] seems to have mind-independent objects and features as constituents’ (2013, p. 271). Martin claims that ‘when one introspects one’s veridical perception one recognises that this is a situation in which some mind-independent object is present and is a constituent of the experiential episode’ (2004, p. 65). — https://link.springer.com/article/10.1007/s11098-021-01618-z

    the conscious “phenomenal” character of that experience is shaped by the objects of perception and their features, where this is understood in a constitutive, rather than merely a causal, sense. — https://www.oxfordbibliographies.com/display/document/obo-9780195396577/obo-9780195396577-0340.xml

    colours are mind-independent properties of things in the environment that are distinct from properties identified by the physical sciences — https://academic.oup.com/book/5610

    Indirect realists reject these claims, and the science of perception supports this rejection.

    That's all there is to it.
  • Indirect Realism and Direct Realism
    How is it an inference, then, and not a sentiment, or a mere prejudice?Banno

    My belief that my experiences are caused by distal objects is a "prejudice". My belief that a distal cow exists is inferred from a) my "prejudice" that my experiences are caused by distal objects and from b) I experience a cow.
  • Indirect Realism and Direct Realism
    It's not based on anything. It's just what seems most reasonable to me. I don't pretend that it's anything more than that.
  • Indirect Realism and Direct Realism
    Yes. It's more reasonable than "an evil demon is deceiving me".
  • Indirect Realism and Direct Realism
    Ah. SO you induce the existence of the world by application of "scientific method"?

    SO does this method involve falsification, or is it statistical?
    Banno

    I believe in the existence of distal objects because I believe that the existence of distal objects best explains the existence and regularity and predictability of experience.
  • Indirect Realism and Direct Realism
    And you deduce, or perhaps infer, the existence of the world, including the things around you, from what the senses present to you?

    How does that work?
    Banno

    Are you asking how induction and the scientific method work?
  • Indirect Realism and Direct Realism


    Yes. Indirect realists aren't idealists. They're realists. They just recognize, contrary to the claims of naive realism, that mental phenomena exist, that distal objects and their properties are not constituents of mental phenomena, that many (even all) of the properties of mental phenomena are not properties of distal objects, that many (even all) of the properties of mental phenomena do not even resemble the properties of distal objects, and that we have direct knowledge only of mental phenomena.
  • Indirect Realism and Direct Realism
    Do you agree that sensory experience provides us with knowledge of the things around us?Banno

    It provides us with knowledge that there are things around us and that our bodies respond in such-and-such a way to sensory stimulation, but that's it.

    Naive realists falsely claim that we know more than this because they falsely claim that distal objects and their properties are constituents of sensory experience. Indirect realists reject these claims.
  • Indirect Realism and Direct Realism
    Again, this is a bad question.Banno

    No it's not. It's a pertinent question that seeks to address the extent to which our body's physiological/psychological response to sensory stimulation allows us to form justified beliefs about the existence and mind-independent nature of distal objects.