• jgill
    3.9k
    Sensations are nervous system-dependent180 Proof

    :up: This sums it up pretty well unless you believe rocks have feelings.
  • lorenzo sleakes
    34
    unless you believe rocks have feelingsjgill

    not rocks...but maybe amoebas do...with no nervous system
  • creativesoul
    12k
    Seems to me that the question presupposes sensations and minds are completely distinct things. I think that that is entirely mistaken.
  • lorenzo sleakes
    34
    I do think that awareness and the material world we are aware of are two seperate things. it is common sense to think we are not looking at ourselves but looking at the world. Matter is directly knowable because it has the ability to create sense-data even if that sense-data is in our brain. The alternative is the compunding of mysteries - the mystery of a unified causally efficatious mind or soul with the mystery of the different sensible qualities and their production.
  • creativesoul
    12k


    Is that directed at me, in response to my last reply???
  • Marchesk
    4.6k
    a mindless sensation is a blue sky before anybody sees it and a thunder clap with nobody around to hear it.lorenzo sleakes

    I don't think mindless sensations are coherent. The sky isn't blue when nobody sees it. It's not any color. What it is are scattering photons, some of which are perceived as blue on a sunny day for creatures with eyes and nervous systems like our own. One thing that makes the blue sky impossible as a mindless sensation is that we only see a small fraction of the electromagnetic radiation when looking at the sky. It would not look blue if we could see the microwaves or radio waves.
  • Count Timothy von Icarus
    2.8k


    But there is no strong argument for believing in this mind dependence. Galileo needed to only say that the color of a falling object is irrelevant to its place in physics, not that it has no color. In distinguishing between primary and secondary qualities Locke needed to only say that certain spatial configurations and movements of matter had the power to create sensations but not that the sensations have to exist "in us".

    I'd argue that the dichotomy is false in the first place, even from a scientific point of view. Minds are ostensibly created by, and part of, nature. Sensations of color, depth, scent, etc. are all natural phenomena. The mental/physical dichotomy was created in the early modern period to help the natural sciences bracket off a whole off a whole set of philosophical questions so that progress could be made on the problems that were proving soluble. It's high time for that firewall to come down, but unfortunately it has become a calcified dogma— something accepted uncritically and defended with religious zeal.

    Corpusclarism, or approximations of it, also seem to be naive, arising long before science and persisting in the face of contrary evidence from the sciences.

    Empiricism gives pride of place to sensation. The models of our world that empiricism has produced has shown that at least the substance of these sensations is dictated by natural phenomena. That is, the Hard Problem may remain, we do not have a good answer for "from whence sensation?" but the fact that changes in the environment can dictate changes in sensations, or that changes in the nervous system likewise affect sensation, even holding the environment constant, is as well established as anything. When you turn the light out, you can't see; likewise, when your eyes or visual cortex are damaged, you also cannot see.

    Science has had to become like an eye trying to see itself. Notably for this analogy, that is something that is quite possible in the natural world; the eye can see itself using a reflection. Science is, in part, a system based on observations through which we try to untangle the how and whys of those same observations. Where things go awry is when dogma declares that such sensations, the ones upon which all empiricism rests, are illusions, somehow unnatural. That is, as you say: "objects are really colored." Yes, this is a fact of the natural world.

    What is interesting to me is that people seem to have an easy time dismissing scent, an ancillary sense for humans, as clearly illusory. "Shit smells bad to us and good to flies because scent isn't real." However, abstractions of space-time, e.g., volume, etc., based on a combination of visual, tactile, and vestibular sensations, are taken as iron clad facts of reality. It seems to me that, if we were dogs, we might go the other way on scent.


    What is key though is that these senses help reinforce a unified model of reality. Senses appear to be used to cross check each other; when we can't tell if a flower is real or plastic by looking at it, we stroke and sniff it. This is why, while a mild degree of synesthesia seems adaptative, we still have extremely distinct sense impressions from different systems after billions of years of evolution (i.e., no one mistakes hearing for seeing)— one sense can cross check the veracity of another.

    There is no intrinsic reason to preference one sensory-based model or another. When we say "color is an illusion, the reality is photons moving through space," this is merely substituting an explanation of a reality in terms of an experience that only exists in one sense (color for sight) for a new model based on the sensation of movement through 3D space, something we experience primarily through three reinforcing senses.

    Corpusclarism, allegedly dead in science, but seemingly very much alive, is the substitution of multiple models based on different types of sensory experience for a unitary model derived from the 'experience of / an analogy to', discrete objects in motion, something experienced in three senses. Thus: "Everything is objects in motion, sense experiences inessential to conceiving of objects in motion are illusory." Hence, "color is an illusion, volume and velocity are not."

    I have to think that something unique to our biology (e.g., that our natural model of spacetime comes from multiple senses) is the motivation here because the entire concept of "discrete objects" has been challenged by physics, corpuscularism itself rebutted, and yet it remains the dominant way to envision the world. Not only that, but the concept is as old as written philosophy. It didn't take scientific revelations to make people buy into it, the position arose ascientifically at the dawn of philosophy (e.g., a world of atoms, elements, Platonic solids, etc.), and has remained in vogue despite countervailing scientific findings. That is, it seems to me that such views are also naive forms of understanding.

    What do we replace this seemingly inborne tendency with? That is a harder question. But it seems to me like a whole description of any given phenomena needs to include our sensation of it. Information, in the sense the term is used in physics, exists relationally. The current dogma involves an unnatural amputation of one half of the relation and the substitution of a magical, unnatural, "eye that sees things-in-themselves," in its place. Thus, neuroscience can inform our understanding of the illusory nature of things like color, but apparently not about the models that we have built atop those self-same illusory sensations?

    A good start would be to try to knock down the tendency towards reduction that corpuscular thinking generates. A common view is that, not only is "color," not "real," but so to social status, recessions, etc. And yet a recession causes massive, observable physical changes across the globe, so in what way is it not "real" in the same sense that rocks are real?

    Recessions are real, but they are incorporeal, a term from Augustine's day that is worth resurrecting. Incorporeal doesn't necessitate "non-natural" or "non-physical," although I will allow that the word is often used that way today. It means simply "lacking a body." (Corpus - Latin for body; "in" a Latin prefix for "un" or "not.")

    Where is a recession located? In physical changes spanning the globe: in unfinished houses in Florida, in empty grocery shelves in Sudan, in government databases— trillions of digital logic gates— and in uncountable neurons and (natural) mental sensations. It exists substrate independently, in information that is naturally isomorphic vis-a-vis its encoding. That is, it is incorporeal, lacking a discrete body.

    Color is likewise incorporeal, it exists in patterns of neuronal activity, in the physical make up of stop signs, in the electrical currents powering lighting traffic lights, etc. It is impossible to study the science of marketing, traffic, the economics of entertainment, zoology, religious symbolism, etc., all natural phenomena without reference to color. Major problems in the social sciences could be resolved if it was acknowledged that, not only are the objects of study complex and emergent, but also incorporeal, but incorporeal in a way that does not entail that they are "less real," or "non-natural."


    The common sense view also says the Earth is flat and stationary.

    A view that was overturned by careful observations, i.e., by sensory experience. Note though that the new view, of a sphere in space rotating on its axis, moving through space around a larger sphere, is also a conception based in sensory experience. To be sure, more sophisticated models look at the system in purely mathematical terms, but mathematics itself is a discipline where visualization is more important than most. The axioms that ground proofs often come from appeals to (seemingly) essential truths about our visual or temporal-spatial sensations. That is, we accept Euclid's axioms because we cannot visualize their violation coherently.



    Sentience is a fuzzy term. But, to your point, slime molds demonstrate intelligence when solving mazes, respond to stimuli, etc. without a nervous system. An interesting behavior of slime molds is that, when food runs scarce, numerous individuals will link together and form a migrating colony that can walk. Essentially, it is a composite body, a unity that appears to utilize a composite sensory system. As the name "acellular slime molds" suggest, a subset don't even have proper cells.

    Problem solving wise, they can do some neat things. People have used them to solve Hamiltonian path problems (e.g., the traveling salesman problem), a class of problem that gives digital computers a hard time. Although, DNA and RNA have also been used to "compute" answers to these problems by creating selection pressures that privilege shorter paths, but we don't think of those molecules as conceivably having any sort of sensory experience.

    main-qimg-f9d47816b27334ccc9a98b4e348a1481-pjlq




    Seems to me like an assertion that will only get murkier as AI advances. Organisms lacking nervous systems nevertheless have sensory systems, so I don't see why the nervous system should be the deciding factor here.

    If the core conceit of computational neuroscience is correct, then sensation is the result of sensory organs working in concert with computational processes. "Conscious" sensation would simply entail some given level of complexity and a "global workspace" in which sensory data is gathered and re-presented to another layer of holistic computational processing. On this view, there is no reason why a sufficiently complex digital apparatus, or a primarily digital apparatus utilizing some biological components for parallel processing, could not experience conscious sensation.

    But that makes sensation an information process, and such processes are generally considered to be substrate independent. So, if that conceit is correct, and it appears to be the number one theory, then you can theoretically build a mind that experiences sensation out of extremely well-crafted steam pipes that have been set up such that they mimic the informational structure of a human brain.

    In any event, until there is a good theory for what exactly causes sensation, this is an isolable debate (i.e., something more specific than "very complex information processing/computation processes," where "complexity," "information," and "computation," are all terms which generate hundreds of articles about how poorly defined and vague the currently are.)
  • lorenzo sleakes
    34
    You are describing indirect realism. There is a complex chain of events leading to colors being created in the brain. I accept this. But this last step is a complete mystery. How did the brain create the sense quality that we experience as blue. I assume it was not invented from scratch. I assume it employed psychophysical bridging laws which may have existed before brains even evolved. Maybe the real external sky doesnt look like the sky in our visual field but that doesnt necessarily mean it has no color. Galileo overreached in saying colors are in the soul. They merely play no causal role in dyamics. A blue stone and brown stone fall at the same rate. That doesnt mean that they are devoid of color.
  • Count Timothy von Icarus
    2.8k


    There is a complex chain of events leading to colors being created in the brain. I accept this.

    Saying "brains create color" is like explaining that "batteries produce electrical current" without any reference to a closed circuit, or explaining that "magnets attract (or repel)" without any reference to what it is in the related objects that are involved in either attraction or repulsion. It seems hard to explain how the physical process of evolution came to involve the "non-physical" trait of color as well.

    A brain in a vacuum isn't going to experience anything. The sensation of color results from an interaction between the sensory system and the environment. Color being "created in the brain" sounds like something ex nihilo; the environment creates the brain and the brain and the environment, together, create color, right?

    But how is this unlike any other physical phenomena? My tires don't "create friction," friction is generated by the interaction of my tires and the road, and friction is itself a composite phenomenon. Covalent bonds aren't created by electrons, or by the molecules they define (except tautologically), but by the interaction of EM forces vis-a-vis relevant set of electrons and protons.

    All physical processes are relational. Imagine any physical entity in a vacuum (allowing for the sake of argument that such a thing can truly exist). What does it do except in respect to other parts of itself? If the entity is undividable, it doesn't do anything, it effectively has no traits, while if it is a composite entity, we can only define its physical interactions in terms of processes between parts of the whole.

    Maybe the real external sky doesnt look like the sky in our visual field but that doesnt necessarily mean it has no color.

    This seems confused. If color only exists in sensation, then the sky has no color without the possibility of sensation existing, no? How can the sky have a color "of-itself," when color is necessarily something that occurs relationally? That's like an electron having a negative charge without relation to the field of which it is a part or any existent positive charge. If the entire universe is just one electron, charge is meaningless, undefinable. If color doesn't exist without an observing entity then does EM charge, isospin, flavor, mass, etc. not exist when there isn't an ongoing relevant interaction?

    The sky observably does have a color. Common denials of this fact generally hew to a reductive line, even if this commitment to reduction is not made explicitly (something which has become more common as reduction has increasingly fallen out of favor). The relationship between a system that experiences color and the object that has color is ostensibly a natural one, even in most dualist ontologies. On the face of it, there is some sort of causal relationship between the colored object, the experience of color, and a source of light.

    The claim that color isn't real, "because it is really just different wave lengths of light reflecting off an object and interacting with photoreceptors that in turn produce a pattern of neuronal action potentials," requires that:

    A. If something can be reduced to something else in an explanation it is somehow "less real" than the things it reduces too.

    B. Everything can be effectively reduced to some fundamental unit of reality, else this devolves into an infinite regress where nothing is real because there is always some lower level of being that negates the reality of the higher. If physical limitations place an epistemological limit on how basic the entities we can know of can be that is above the ontological basement, then we only ever deal with "non-real" entities in the first place.

    C. Contained in B is the assertion that no information is lost in this reduction, which clashes with the relational nature of physical phenomena. For example, my coffee mug is hotter than the table it is sitting on. I can reduce this statement into an analysis of the relevant systems' composite parts, but by the time I reduce it down to individual molecules I have lost the concept of heat. How can a molecule have velocity in relation to nothing but itself? Thermodynamic systems do not contain heat, heat is defined by a boundary condition.

    None of these points seem particularly well established. Again, I think this flawed way of reasoning is a biproduct of the human sensory system itself (see above). Hence why it predates anything resembling modern science by millennia and remains remarkably robust even in light of evidence against such a view (e.g., why should we think things are really just the motions of smaller things anymore when we have evidence that these apparently fundamental smaller things are really fluctuations of a field and only definable in terms of the entire field, the part explained by the whole, or why believe in the aforementioned fields if they can be reduced to information theoretical datum?)

    They merely play no causal role in dyamics.

    Cars are bodies in motion. They stop at red lights and begin moving again when a green light appears. Galileo bracketed dynamics to a set of simple problems, but we now look at physical systems much more holistically precisely because this gives us a better understanding of the world and allows us to make better predictions about it. The change in motion of cars due to color is part of any holistic explanation of traffic patterns.
  • creativesoul
    12k
    I do think that awareness and the material world we are aware of are two seperate things.lorenzo sleakes

    I never said otherwise. I criticized the presupposition that sensation and mind are completely distinct 'things'. Seems to me that the former are part of the latter in such a way that complex minds such as ours evolved - over enough time and mutation - from simple sensation(s). In other words, without sensations there could be no minds.
  • L'éléphant
    1.6k
    On the contrary, I've stated a demonstrable biological fact (re: cell biology). Feel free to refute it with more than mere speculation.180 Proof

    ↪180 Proof
    you have proven nothing. some people think that even individual living cells may have some form of sentience in which case a nervous system is not even necessary. But even if a nervous system is necessary does that mean insects or clams are sentient?
    lorenzo sleakes

    ↪lorenzo sleakes
    :roll:
    180 Proof

    haha! This is the kind of exchange that's pervasive here in the forum. :lol:
  • L'éléphant
    1.6k
    @lorenzo sleakes ,

    To say "you have proven nothing" is ignoratio elenchi (failing to see the point of @180 Proof's response).
  • lorenzo sleakes
    34
    Sensations are nervous system-dependent.180 Proof

    I agree that the sensations that we experience are nervous system-dependent. But the question is how. Are you elimitative and believe the actual sense-data "red" is nothing but the nerve signal? If not then how does the nervous system create such sensible qualities. There are some theories but I dont think science has gotten very far in discovering such NCC.
    Most believe that colors never existed until brains created them for the first time ever. Maybe its right but I question it: the idea being that behind the yet to be discovered NCC are deeper psycho-physical laws that may not be nervous system dependent.
  • 180 Proof
    15.4k
    I agree that the sensations that we experience are nervous system-dependent. But the question is how.lorenzo sleakes
    This is a scientific problem and not a question philosophers alone can answer, or even pose adequately, insofar as philosophy's domain is conceptual-interpretive, not theoretical-testable.
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