Re: Qualia and the Galactic Loony Bin
Wed, 23 Jun 1999 11:37:10 -0700

Harvey Newstrom, <>, writes:
> Hal <> wrote:
> > I may have been unclear about this "replay". The brain is entirely
> > normal and fully functioning. It's just that we "happen" to be giving it
> > exactly the same inputs we did on an earlier run.
> I must have missed something. If the second brain is normal and fully
> functioning, how is it different than the first brain or any brain? What is
> being replayed here? The test? I though you had something hooked up to the
> brain and was forcing it to replay the same thoughts it had earlier. If its
> thoughts are being dictated from the outside, it is not conscious or
> generating thought. If its thoughts are being self-generated from the
> inside, then it is conscious and generating thought.
> I guess I am having a hard time following all your examples. What exactly
> is it that you are trying to prove? Every example seems to devolve into a
> discussion about the minutia of the example. What is the overlaying
> supposition you are trying to support?

I am sorry that my examples have seemed confusing. What has happened is that I gave the first experiment of the divided brain. You responded that there is no consciousness because there is no flow of information, it is just a pattern which is being imposed from the outside.

I said then, if that were the case, that the flow of information and connection and causality were the true determining factor of consciousness, then how would you explain what is happening in this *other* experiment?

This is where I think I have confused you, because I tried to describe another kind of experiment and you were still thinking in terms of the first one.

The overlaying supposition I am trying to support is that none of these explanations where consciousness is based solely on information hold water. All have serious inconsistencies and all are implausible if you look at them closely enough. There must be something wrong with our fundamental reasoning on these problems.

The divided-brain experment shows that this is true with regard to the pattern model, and the other experiment which I have tried to describe to you yesterday shows that this is true with regard to the information processing, connection based, causality based model that you support.

Does that help give you an overview of what I am trying to do here?

My message with the *second* experiment, the one which attempts to lay the groundwork for showing that causality is not a coherent concept for a model of consciousness, is at I will explain it again and perhaps try to eliminate any superfluous elements.

The point is to show that there is no difference between a causally connected brain and a passively replaying one, or at least that the difference is so trivial that it is almost inconceivable that it could be the cause of consciousness. I know that you disagree with this stated in such bald terms, but realize that it is a conclusion, not an assumption.

You have to go through the steps of the thought experiment and the reasoning behind them to see how we come to the conclusion, you can't just deny it because it seems implausible. You need to reject the premise of the experiment, or one of the steps involved.

The premise is that if you run a brain (or perhaps a brain simulation) through an experience where you supply the inputs and it processes the data normally, it will be conscious. I think you will agree with that. We also have to assume that the brain can be made to run in a deterministic way, without any physical randomness. This would be more plausible in the case of a brain simulation but perhaps it could be arranged with a real brain.

It follows that if you run a brain through the same experience twice, with the same initial state and the same inputs, it will be conscious both times. That follows because it satisfies the conditions of the premise, and the premise says that whenever you satisfy those conditions it will be conscious. It is an intermediate conclusion of the argument, and you have to reject the premise to reject this conclusion.

We now introduce the notion of making a recording of all the internal activity of the brain during the first run, each neural firing or whatever other information was appropriate depending on how the brain works.

We then add a comparison during the second run of the activity generated during that run with the recorded activity from the first run. Imagine comparing this neural activity at each neuron. The two sets of data will match, by the premises of the experiment, because we are exactly repeating the first run.

Finally, at each neural element we substitute the recorded data for the actively generated data. We block the actively generated signals somehow, and replace them with the signals from the recorded first run. Since these two signals are completely identical, it follows that there will be no difference in the behavior of the brain. Substituting one data value for another identical one is of no functional significance.

Now we claim that the result is not "actually" a case of functional information processing, but merely a passive replay. Each neuron is given inputs from a recording, and its responses go nowhere. This is essentially the same as the case where you said there would be no consciousness.

The point is that we took a situation where the brain was conscious, by the premise of causal connectivity based functionalism, and by substituting one set of signals for an identical set of signals, which is arguably no substitution at all, we produced a brain which is passively running a replay. So either this seemingly ineffectual substitution has eliminated consciousness, which seems hard to understand, or passive replays are as conscious as functional brains, which you deny.