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by ewjordan 6143 days ago
Scientists can ask me about what the experience of "red" is like, and I can tell them that it's not quite like blue or green, and can point to it, but the experience itself (like all experience) remains a completely private matter for me.

Most emphatically, no. Well, I suppose yes, for now, but that's only because your complete brain state is effectively hidden from the scientist because we don't have the technology to get a good picture of what's going on inside. Give us a decent real time high resolution scanner, and your "private" experience is just another data set on a big computer somewhere.

A C++ program would be pretty damn inscrutable, too, if we couldn't core dump when things went wrong...

Look at any red object and compare it with any "scientific" description regarding wavelengths and retinas, neurons, synapses, neurotransmitters, visual cortexes, atoms, molecules, or what have you. Clearly none of these thing are in any way related to what it's actually like for you to see that red object.

Look at any Youtube video and compare it with the "computer science" description, with bits and bytes and encodings, filtered through the Flash player, etc. One could argue that these things are clearly unrelated to some kid getting whacked in the nuts by his brother, but one would be wrong.

I'm extremely reluctant to accept the notion that our physical brains have no relation to how we experience the world (an idea you seem eager to accept) - we don't understand it very well, true, but that's partially because we're pretty stupid, and partially because we're not very far along in understanding it yet.

All that it takes for you to claim subjective experience is for your brain to be programmed to respond to the question "Do you have subjective experience of the color red?" in the affirmative. To me, that's a lot easier to swallow that that's the case than to imagine there's Magic going on here...and yup, I'm happy to apply the same logic to my own experience, I don't attribute anything special to it other than a mere self-reinforcing computational delusion.

Personally, I find that a far more fascinating thing than the alternative, anyways...

Now, you may well believe that what's going on when you look at a red object is "really" some interaction between what those scientific terms describe in some model of what's going on with your brain, sensory organs, etc. But this requires a sort of suspension of disbelief, as you have to set aside your actual "subjective" experience of the red object itself

It really doesn't, though, unless you already ascribe something mystical and aphysical to this "subjective experience," begging the question.

Someone else brought up the idea of a pzombie, someone that responds in every way as if they had subjective experience, but really doesn't. Getting past WTF that would actually mean, since nobody ever bothers to define "subjective experience," I think the heart of the question is this: if a pzombie responds internally as if it had subjective experience as well as externally, then isn't that enough for us to say that it does? That's why I'm happy to write the whole thing off as a non-issue, even when thinking about my own experience - the fact that I believe I experience "red" means nothing more than that I believe it.

IMO anyone arguing against that first has to figure out what it means for a pzombie to lack subjective experience even though it looks, walks, talks, acts, and thinks as if it did. Otherwise the argument is pretty pointless, kind of like asking what the world would be like if the prime number theorem was false.

2 comments

>Give us a decent real time high resolution scanner, and your "private" experience is just another data set on a big computer somewhere.

That huge dataset still won't tell you what it's like to see red, though. It will just tell you what happens in the brain when someone sees red.

>It really doesn't, though, unless you already ascribe something mystical and aphysical to this "subjective experience," begging the question.

You don't have to do anything of the sort. You just note that there's nothing in the physical description which corresponds to the subjective quality of your experience. To make it more concrete, there's nothing that explains why seeing red isn't like seeing blue and vice versa.

constantly asserting that "it just isn't" does nothing for your case. hypothesis must be differentiable via making different predictions about the world. otherwise they're not really different.
(I'm not parent, I'm the one who originally asked the question.)

Certainly, a _scientific theory_ is judged based on its predictive power. This is why I mentioned my opinion, earlier, that science is "the art of useful fiction." The goal isn't to achieve truth but to predict.

Philosophy, on the other hand, is concerned with what is _really_ true, not predictions.

Certainly, the experience of qualia has no effect demonstrable to an outside observer. That doesn't make it any more or less real. I experience, therefore it must exist. I merely can't prove it to you. The great thing is that you can prove it to yourself. All you have to do is pause for a moment and rationally examine what you feel.

If your interested in an attempt to explain it from a materialist perspective, you may wish to look at Roger Penrose _The Emperor's New Mind_. He argues that consciousness is intricately tied to QM. Or at least I think he does... It's difficult reading and I haven't read the whole thing yet!

It's on Google Books, here: http://books.google.ca/books?id=oI0grArWHUMC&dq=The+Empe...

The first chapter provides an excellent explanation of qualia.

what is _really_ true IS what makes the best predictions. Otherwise in what sense is it true? Qualia has no effect demonstrable to an inside observer because you have no other data points to compare to. You have only one data point: your own consciousness.
>what is _really_ true IS what makes the best predictions. Otherwise in what sense is it true?

That is the anti-realist position, but it could be true in the sense that it corresponds to the actual nature of reality, if you are a realist.

> You have only one data point: your own consciousness.

Yep, and that is the data point that physicalism doesn't seem to be able to account for.

you're covering it up with the term "actual" what does that mean?

your second assertion doesn't make any sense either. "account" would imply that pzombies would be different from "normal" normal people I guess?

Neither will saying "it just does." How do you think that seeing a detailed brain scan would tell you what it is like to see red? It's extraordinary that you think the burden of proof is on those who simply deny the near-inconceivable possibility that it would.

The problem is precisely one of predictions. Physicalism doesn't predict the existence of conscious experience. (And if you really think its necessary to give an argument for the existence of these experiences other than "we all have them and know that we have them," I am not sure what to say -- you are simply in denial.)

Physicalism doesn't predict the existence of conscious experience. (And if you really think its necessary to give an argument for the existence of these experiences other than "we all have them and know that we have them," I am not sure what to say -- you are simply in denial.)

It is absolutely necessary to give an argument for the existence of these experiences.

I know that you believe you have them, and that I believe I have them, but that doesn't mean that they have any tangible reality, it just means that our brains store things in a way that they will respond "yes, I have conscious experience."

Alternatively, should I accept as real everything that a person believes they experience? A schizophrenic's voices are real? A memory of a past trauma that is, in fact, a false memory, proves that the past trauma is real? This is a very dangerous path to walk, accepting the validity of introspection as a means of investigating the world...

>I know that you believe you have them, and that I believe I have them, but that doesn't mean that they have any tangible reality

It does in the case of experiences. I can't even conceive of what it would mean to be mistaken about the very fact that you are having experiences. It would be a very different sort of mistake from that of being mistaken about the _object_ of an experience (thinking that you are hearing voices when there aren't any, etc. etc.)

Also, your use of the word "tangible" is very odd in this context. Almost by definition, nothing could be more tangible than an experience.

>[I know that] I believe I have them

So, do you believe that you have them or not?

the burden of proof clearly lies with those who posit the existence of an unobservable quality to cognition.
I'm not positing the existence of an unobservable quality to cognition. What gives you that idea?
I just reread the first chapter of Penrose's _The Emperor's New Mind_ so this is based off of it.

Let's simplify the problem to just conversation, for the sake of simplicity. Suppose we have a program that can pass the Turing test... But the way it is constructing it's responses is only a more capable version of the emacs psychiatrist. Does it have consciousness?

I posted a link to ENM in another post. Maybe look at the first chapter. It hits the nail on the head, IMHO.

EDIT: Or even just read the first few pages... It seems to introduce it decently, if your short on time.