| | GW wrote: That a substance is separate from another substance does not entail that it must be able to exist independently of the other. A cow is a substance separate from the grass on which it feeds. We ought not to conclude that a cow is not a separate substance just because it cannot exist independently of its food source."
I replied: “I was using ‘substance’ in a different sense. I should have said that if a soul or a consciousness were an entity rather than an attribute or a property, it could exist independently of a body. How is an entity different from a substance? Clearly the cow to which I referred in my counterexample can also be described as an entity; thus, my counterexample still stands. I meant metaphysically independent it in the sense of an entity vis-à-vis its attributes. The attributes are part of its identity; they cannot exist independently of it. The grass is not part of the cow’s identity. Even though the cow needs to consume the grass in order to survive, you could remove the cow from the grass, and the cow would still exist. You cannot remove an entity from its attributes; its attributes constitute its identity.
I wrote, True; one could lose one's sense of sight, for example, and still have memories, imaginations and dreams in the form of vision. What I meant is that a consciousness couldn't originate without physical sense organs, and that includes a divine consciousness.” In the "Objectivism and Atheism" thread, I refute this position by explaining how it is possible that, given materialism, a consciousness could be 'built' (probably with the help of cloning) to have inborn memories, sense impressions, beliefs, etc. Its consciousness would originate through the careful, neuron-specific contruction of the brain, not through sense organs. Yes, and I answer you there as well.
I wrote, “You mean that the soul, once it acquired information from the external world through the five senses, could leave the body and continue to exist without it? Not if a vital, functioning brain is required for memory and imagination, which it is. A functioning brain may be required for memory and imagination given the empirical conditions of the actual world. But surely, given materialism, there are other material entities (proton computers) that could support consciousness. How would you get a consciousness into a proton computer? You’d have to separate it from its physiological context just in order to make the transfer. Nor is there any evidence that a consciousness could be created using a proton computer. Consciousness, by its very nature, is goal-directed or purposive, an orientation that makes sense only if the conscious entity has something to gain or lose by its actions – which is to say only if the entity is a living organism. It is the function of a consciousness to facilitate an organism’s survival.
I wrote, “Without a brain, there would be no gray matter to process and store the memories and information gained from one's perception of the external world.” Right, but there could be pink, yellow, or orange matter to process and store the memories and information. Given materialism, any sufficiently complex computing system will be able to support consciousness. And we can paint the component parts, i.e. the 'matter', in any color of the spectrum. ;) I’m not sure what you’re proposing here. The important point is not the color of the brain’s matter, but the fact that consciousness is an attribute of the brain and sensory nervous system and cannot exist independently of it. Are you proposing some kind of “transfer” of the mind from the brain’s gray matter to some other kind of matter? That clearly would be as impossible.
GW wrote: "You assert without substantiation that the activity of the person's brain and sense organs is equivalent to his knowledge and awareness."
I replied: “How can you have knowledge and awareness without the activity of the brain and sense organs? You need the sense organs to gain the information, and the brain to process and store it.” My point was that the activity of the person's brain and sense organs is not equivalent to his knowledge and awareness. My assertion concerns identity. Your response suggests that brain activity is a necessary condition for knowledge and awareness; you say nothing about whether knowledge and awareness just are brain activity. A certain level of brain activity is both necessary and sufficient for consciousness. If you have that kind of cerebral activity, then you have knowledge and awareness. Knowledge and awareness are not things that exist alongside the brain and interact with it; they are simply its subjective manifestations.
I wrote, “We know that unless it [i.e. perception] exists in some sensory form, which is determined by the nature of the physical sense organs, perception is impossible, which means that perceptual awareness must be physical.” I'm thinking of the simple propositional identity x*x=x^2. My awareness of this equation itself is not physical. The variables and the number are merely placeholders for immaterial notions, which is proven in that the variables and numbers can be exchanged with any numerical or alphabetical signs of a similar set. I was talking about perceptual awareness. You’re referring to conceptual awareness – i.e., to the awareness of a proposition, which the symbols in your equation represent. But even there, you need some form of notation in order to symbolize the proposition and its concepts. You also need a physical brain to grasp the proposition.
I continued “E.g., vision is the conscious manifestation of the eye's operation; hearing, of the ear's operation, etc. In the same way, thinking, memory and imagination are a function of the brain. So perception, awareness and knowledge must be part of the physical body.” Just because the eye is physical, it does not follow that the conscious manifestation of the eye's operation is physical as well. What I said is that the conscious manifestation of the eye’s (physical) operation is vision -- a conscious experience -- not that the manifestation is “physical," although it is part of the physical body. You’re not denying that vision is the conscious manifestation of the eye’s operation or asserting that vision can exist independently of its operation are you? Thus, you cannot justifiably say that thinking, memory, and imagination are just a function of the brain, for in saying this you tell me the source or origin of the mental phenomena but not what mental phenomena are-- still less that they are physical. Mental phenomena are mental phenomena; they are understood ostensively, by direct experience, but they are nothing more than the subjective aspect or manifestation of the function of the brain (and sensory nervous system). They do not exist in isolation from it as separate and independent phenomena.
I wrote, “But there's a very real sense in which one's mental content can be reduced to the physical state of the brain -- the sense in which it is simply a manifestation or property of the brain's physical state.”
Seeing that you've never sufficiently supported the assertion that one's mental content is simply a manifestation or property of the brain's physical state, this assertion hardly justifies the further assertion that mental content can be reduced to the physical state of the brain. Well, it has to be a manifestation or a property of the brain’s physical state; otherwise, it could exist independently of it, which, as I have shown, it obviously cannot do.
I wrote, “You're evidently assuming that the mind somehow acts upon the brain -- i.e., is causally efficacious with respect to it.” I've supported this assumption (that the mind causally influences the brain) with a number of examples. For instance, in the 'Objectivism and Atheism' thread, I wrote that when the mind examines mathematical proofs, certain conclusions are drawn from supporting logical and mathematical axioms. These axioms themselves, as mental propositions, and the mental analysis of their influences and relationships, cause and determine the nature of the conclusions drawn from them. Right, I read that. How does that prove that mind acts upon the brain – as if the mind could exist independently of the brain and influence it? All it proves is that certain mental actions (which are simply the subjective manifestation of brain actions) cause and determine other mental actions (which are themselves a subjective manifestation of brain actions). It doesn’t prove that the mind and brain are independent entities that can influence each other’s behavior.
I wrote, “But the mind could only act upon the brain, if it were independent of the brain, which it is not.” You assume that the mind is not independent of the brain, and then proceed to wonder how it could possibly be that the mind could act on the brain. That is not a rational method. I don’t “assume” that the mind is not independent of the brain. That the mind is not independent of the brain is obvious from everything we know about the mind and its relationship to the brain. When one’s brain is adversely affected by aging, disease or injury, one’s mental function is affected correspondingly. When the body dies and the brain ceases to function, all evidence of mental functioning ceases as well. There is no arbitrary “assumption” here; the premise that the mind does not exist independently of the brain is based on solid empirical evidence. The whole point is that if it can be demonstrated that the mind acts upon the brain (which I think it can), And your evidence is . . . ? then it would follow that the mind is, in a substantial sense, independent of the brain, and that you would need to revise your position that the mind is not independent of the brain. Good luck with that! :)
I wrote, “Nor does the brain act upon the mind; that too presupposes that the mind is independent of the brain. There are not two separate organs, the mind and the brain; there is only one: the brain, which a person directs and controls through the mental aspect of his brain's activity.” As I anticipated, you are very quickly slouching toward reductive materialism. Is or is not the mental aspect of the brain's activity physical? It’s physical in one respect, but not in another. It's physical in the sense that it is a property of a physical organ, which it does not exist independently of. It isn't physical in the sense that a mental entity, like an idea or thought, is not something you can see or touch like a physical object. If it is non-physical, then you must assume it is at least ontologically distinct from the brain. Why? I don’t see this at all. If, as the evidence demonstrates, mental activity is simply the subjective aspect of brain activity, then the mind is not ontologically distinct from the brain.
GW wrote: "You aren't getting it because you aren't taking personal identity seriously."
I replied: I have no idea what this is supposed to mean. Care to explain? Well, I gather from your earlier response that personal identity consists of a set of mental experiences joined in some way. But surely personhood is not just a stream of mental phenomena, for there is surely a person who cognizes these phenomena and exists throughout them. The point is that physical continuity is not sufficient for determining the identity of the person, since truths having to do with physical composition do not tell us about the identity of the person. But it is the physical person (in a certain state of vitality) who has the experiences. Without the physical body, brain, sensory nervous system, etc., there wouldn’t be any personal identity. You evidently believe that the mind and personality have an identity that is somehow independent of the physical body – that you can damage the physical brain and body – even destroy it – and that the mind and personality will continue to function. As I've indicated, I don't see how that could possibly be true.
I wrote, “[...] but what I was getting at is that the thunder and lightening are not independent of the discharge of static electricity; they're simply manifestations of it, in the same way that consciousness is not independent of the brain's activity, but is a manifestation of it.” But thunder and lightning are both physical, so it makes sense to say they are both manifestations of the discharge of static electricity. This is not the case for consciousness and brain activity, since the former is non-physical and the latter is physical. Hence, the analogy is poor. No analogy perfectly duplicates the idea it illustrates. You have to abstract the relevant similarity. The relevant similarity here is that the same thing can have different manifestations. Yes, in the thunder-and-lightening example, both manifestations are physical, but there’s no logical requirement that if the same thing has different manifestations, they must necessarily be physical.
I wrote, “The mental and physical are normally contrasted to each other, but I think that in strict metaphysical terms, this is a mistake, unless you are contrasting mental attributes with physical attributes. In that case, of course, you wouldn't "reduce" one to the other, any more than you'd reduce size to shape or color to texture. But there is a sense in which you can meaningfully "reduce" the mental to the physical, namely, the sense in which the physical brain and senses are the organs of thought and awareness.” Another bad analogy. You can't reduce size to shape or color to texture, but you can reduce all of these physical properties to the physical object they are all predicated of. What does that mean? “Reduce all of these physical properties to the physical object they are all predicated of”? The physical object just is all of the properties predicated of it; there is no Lockean "substratum" underlying them. Therefore, the only thing it could mean to reduce an object's properties to the object itself is to recognize that the object is nothing more than its properties. But if so, then one can also reduce all of an animal’s properties, including the property of consciousness, to the physical organism of which they are predicated. However, in taking about mind and brain, we're not discussing multiple, metaphysically similar aspects (size, shape, etc.) of a single thing (a material object), but rather what is alleged to be a single aspect (mind) of a single thing (brain). True. So, of what relevance is this? In any case, the million dollar question is whether you accept that thought and awareness just are the activities of the brain. I'm interested in hearing whether you think so. I think they are in one respect, but not in another. They "just are" the activities of the brain viewed introspectively – in the same way that the morning star "just is" the evening star viewed before sunrise. In another respect, however, the morning star is not "just" the evening star, because the morning star is "Venus viewed before sunrise" whereas the evening star is "Venus viewed after sunset." In this respect as well, the mind is not "just" the brain, because the mind is "the organ of thought viewed introspectively" whereas the brain is "the organ of thought viewed extrospectively."
- Bill
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