Thomas Ash

Well, I meant logical patterns in the physical flow of one neural state to another - but I assume you know that. Don't worry, I'm not implying that you think logically at all .

But I'm not talking about analyzing our reasons, I'm talking about analysing our experience of thinking those thoughts (ie. mental events together forming our conciousness) and how our brain 'knows' about this if it's just giving it off as a sort of projection. If it knows about it from "sense data" as you say, how does it sense it, particularly if it's just a secondary effect of it's own action? Are you suggesting there's a special organ for sensing mental events (but only our own)? If not, then what?

True, but this is different as it suggests an intrusion into the causal chain according to the laws of physics of neurons firing. But as I said I don't think it really causes a problem for a more broadly defined determinism, as the mental events must obey a sort of causal chain of their own or else be random (which obviously doesn't provide libertarian free will, just randomness.)

I think you misunderstood - I was just saying that our mental events shouldn't able to affect our physical brain without some explanation of how this works.

You're right, I should include supervenience. What are your personal thoughts on it by the way?

Thanks ,

Thomas

Thomas Ash

You're missing the point. If Identity Theory holds that physical events are exactly equivalent to mental events, then surely all physical events should have equivalent mental events. Even doorhinges swinging open should have a mental correlate.

How is this idea wrong?

Thomas Ash

Yes, and the obvious nonsensicalness of this proposition is a futrther argument against Identity Theory, isn't it?

I tend to agree - but how do we know this? We see a corellation, but how do we know, for instance, that the causation doesn't run the other way round? I suppose because we see external physical stimuli like light hitting the eyes triggering new neural events without reference to the mind, but it's a thought.

John Page

Yes, this is the currently accepted concept. Historically there has been some belief that the eye was an "active" organ sending our rays to "see" things.

Thomas Ash

Come to think of it, there's a further, obvious argument why the first theory I gave - straight mind-to-brain causation, can't be right. It's that when we alter the brain directly physically, conciousness is also affected. An example of this is the physical stimulus of light hitting the eye setting off a chain of neural events which cause mental events. The brain can also be altered to affect the mind either by mind-altering (note we call them mind-altering, though in fact they're brain-altering!) drugs or more directly by anaesthetics which render you unconcious by inhibiting the action of anaesthetics by rendering you unconcious. The fact that stopping neuron activity in a certain part of the brain can stop conciousness entirely suggests somethijng more - that the mind doesn't have a separate existence from the brain, but this just leaves the question of how our conscious experience feeds back to the brain still more perplexing.

Can anyone help me out here?

wordfailure

The first conclusion in question is that epiphenomenalism has been dealt a fatal blow by your objections. I don't think it has. Say my wife is standing at the closet trying to choose between the red dress and the blue dress. If consciousness is epiphenomenal, how does the decision to wear the blue dress get back from the consciousness to the brain? The epiphenominalist would probably say this is a faulty assumption about what is really happening; the decision doesn't get back to the brain. The brain is actually doing the deciding directly, conscious awareness being incidental steam escaping, so to speak. It seems to me that you have not demonstrated that thinking about consciousness must be different from this. I think this may all relate to how our brains work. The way our brain physically functions, "visualizes" brain and mind independance, for example, may hinder comprehension.

The second conclusion in question is that the implication of Identity Theory that "every physical event, from the 'decisions' of a vending machine to the action of a doorhinge, has a mental correlate" is a problem. Consider, for example, these discussion boards on your computer. Would you say that every thought expressed or possibly expressed has a mental correlate? They are in a form we can accurately distinguish and manipulate with only 26 letters. Your computer does it with only 2 digits. The analogy may not be perfect but it seems to me that whether or not every physical event has a mental correlate is a science question rather than a philosophy one, so cannot be decided with a philosophical "yes" or "no".

The third conclusion is "This is what takes it outside the realm of science and the scientific method and into the realm of philosophy". I consider philosophy to be how we are forced to cope with things we don't know or understand. With science is the hope of understanding. It is science that has my attention on the topic of consciousness.


I think epiphenominalism is a contender. I do not know.

John Page

Agreed, but progress is being made. Here's an interesting Churchland paper that somebody posted a link to in another thread.

IMO the radial links integrating the sensory and other experiences from other brain areas and the 40KHz waveform are the most likely contender to explain the simultaneity aspects fo connsciousness (the brain being a mssively parallel process).

Cheers, John

ComestibleVenom

Not only is it not clear, I think it's patently false. It's like saying that heat is *ontologically* distinct from the motion of molecules.

Hardly absurd, since in such a language game zombies would be a confusing self-contradiction.

In the sense that our cognitive systems extend past our scalp, into our computers, calculators, hand gestures, I could grant that the mind and the brain are not one and the same. But that is simply an extended sense of the notion that the brain is our mind, not really a contradiction of it.

btw, could you give a brief description of Kripke's argument.

Not only is this idea not absurd, it's necessarily true unless we invoke some sort of spiritual animus that makes the mind. THAT, I count as far more absurd and unpalatable then the idea that the physiology of the human mind/brain. Paul Churchland and Daniel Dennett both have very effective counters to Jackson's self-contradictory thought experiment.

This again is like saying that the activity of a computer causes computation. That's just a confusion about the nature of inter-theoretic reduction. The activity of the computer is simply the computation, as certian physical human activities are our mental activities.

God Fearing Atheist

The arguments against functionalism and other sorts of Strong AI work equally well against Indentity Theory, methinks.

There are, however, a number of good specific anti-Indentity Theory arguments. For example, Block & Fodor (1972) point out that it is very unlikely that there are (assuming the coherence of IT in the first place) only one possible type of neurophysiological state with which mental states are indentical. Consider, for example, non-human animals, or space aliens with a completely different sort of biology.

Block likened IT to a sort of "neuronal chauvinism" (1978).

-GFA

God Fearing Atheist

ComestibleVenom,

Just a few points:

1) Heat is not ontologically distinct from the motion of molecules. I think that sort of "macro-micro" distinction is an important one to sorta get a grasp on the concept I and other have in mind, but it obviously has its limits. Like heat to motion, i think consciousness is a global property of the brain; a causal result of the workings of neurons, synapses and so forth, but one that cannot be ontologically reduced to those processes.

2) Kripke suggests that if mental states are indentical to functional composition (or to the biological brain states of the indentity theorist, as he frames the argument), it would have to be a nessecary truth in the same way the statement, "heat is indentical with the motion of molecules" is a nessecary truth. In both cases, the expressions on either side of the indentity statement are "rigid designators"; that is, the expression indetifies the object it refers to in terms of its essential properties.

This feeling of pain that i now have is *essentially* a feeling of pain because anything identical with this feeling would have to be a pain, and this brain state is essential a brain state, because anything indentical with it would have to be a brain state. So it seems that the functionalist/indentity theorist who claims that pains are *nothing but* brain state or functional composition are forced to hold both that it is nessecarly true that in general pains are brain states, and that is is nessecarly true that brain states are pains. *But*, it doesnt seem right to say either because it seems easy to imagine that some sort of being could have brain states like these without having pains and pains without having those brain states.

3) I think the Churchlands, Dennett, Putnam, etc have all been sufficently addressed, in particular by Nagel, Jackson, Searle, Kripke, Crick, and Chalmers (although i dont agree with Chalmers on an awful lot).

4) I dont understand why my position involves a "spiritual animus". I fully agree that consciousness is a physical thing, the result of purely biological processes. However, i understand that it makes no sense to deny the existence of first-person mental states (like Dennett), which obviously exist, or to try to ontologically reduce them to their third-person causes.

-GFA