The flawed path you’re attacking is not one I followed, and so it just seems a strawman to me.
But if you’re going to argue that qualia don’t exist, then I’ll have to believe that you’re the one confused, not me—the existence of qualia, the existence of my current subjective experience is the only thing I know for certain, more certain by far than I can of the existence of the physical world. Whether I’m in the Matrix, or in a true flesh body, or if perhaps my consciousness is simulated by hordes of monks using abacci to simulate my neurons… whether reality itself is a lie… I can never place absolute certainty on those things.
But one thing I know for certain: I experience qualia, more certainly than 2+2=4.
But if you’re going to argue that qualia don’t exist, then I’ll have to believe that you’re the one confused, not me—the existence of qualia, the existence of my current subjective experience is the only thing I know for certain, more certain by far than I can of the existence of the physical world.
No, I am not saying that qualia are something well-construed which does not exist, like a tea pot orbiting Mars, or like an aquatic dinosaur living today in a lake in Scotland. I am saying that the concept of qualia critically misconstrues the evidence. In fact your own statement here nicely illustrates what I take to be the reason the concept of qualia exists and persists, which is that by its very conception it provides the philosopher with something that he is supremely confident in. To employ my example: the philosopher does not know whether he is looking at an apple, or a plastic fake, or whether he is a brain in a vat hooked up to a computer simulation of an apple. What can he do to escape his uncertainty which grows with each new possible scenario that he imagines? Why, in the end it turns out to be simple: he declares that all these possibilities which he is unable to tell apart share a common element, and that element is a common subjective experience. Thus he turns his own failure (to tell things apart) into a supposed success (the supposed discovery of a common element). Voila: qualia. The concept is in effect defined to minimize uncertainty. So for you to write:
the existence of my current subjective experience is the only thing I know for certain
strongly confirms my own view about the nature of the philosopher’s concept of subjective experience, of qualia.
I always enjoy reading your contributions to these philosophy of mind debates, even when I disagree on some fairly minor points.
What can he do to escape his uncertainty which grows with each new possible scenario that he imagines? Why, in the end it turns out to be simple: he declares that all these possibilities which he is unable to tell apart share a common element, and that element is a common subjective experience. Thus he turns his own failure (to tell things apart) into a supposed success (the supposed discovery of a common element). Voila: qualia. The concept is in effect defined to minimize uncertainty.
This is a rather Wittgensteinian diagnosis—it reminds me of Philosophical Investigations §308, for instance.
To play devil’s advocate I shall temporarily pretend to believe in qualia.
If I am unable to distinguish between visual stimuli A and B then some properties must be remaining the same each time, namely whatever it is that predisposes me to judge that present stimuli stand in such-and-such relations to other stimuli. (E.g. “this green thing, whatever it is, has a lighter, more garish shade than the leaves of that tree over there.”) Qualia are precisely those properties of my subjective experience which enable me to make these judgements. To be conscious of X at all implies the ability to synthesize X with other mental contents Y and make judgements like the comparison above. So since I am conscious, my mental contents must have qualia.
Therefore, I can no more doubt the existence of qualia than I can doubt the fact that I am conscious.
If I am unable to distinguish between visual stimuli A and B then some properties must be remaining the same each time,
Not necessarily. Here’s what could be happening in your brain and which could underlie your power of discrimination: there is some operator which takes two inputs and produces an output “same” or “different”. Since this operator could, in principle, be anything at all, then it is in principle possible for any two arbitrary inputs to be assessed as “the same” by the comparison operator. They don’t have to have anything in common.
That’s in principle. In reality, we don’t expect brains to be so badly designed. We expect that under normal conditions (though not necessarily in highly artificial laboratory setups which test the limits of perception, such as for example “change blindness” experiments) the comparison operators which operate inside the brain output “the same” only when the two inputs are from objects in the real world which are really pretty similar in some important way. And in the case of an apple versus a fake plastic apple, there is something that does remain the same: the pattern of light traveling in the space between the object and your eyes.
But this common pattern of light is surely not a quale. It’s not even in the brain. In fact, the sameness of the two patterns can be demonstrated by taking a digital photo of each scene and then having software compare the two photos. Can you take a photo of a quale?
Qualia are precisely those properties of my subjective experience which enable me to make these judgements.
We have jumped from “some properties must be remaining the same”—which I’ve acknowledged is probably typically the case in normal circumstances—to “properties of my subjective experience”. So we’ve slipped in the term “subjective experience”.
The flawed path you’re attacking is not one I followed, and so it just seems a strawman to me.
But if you’re going to argue that qualia don’t exist, then I’ll have to believe that you’re the one confused, not me—the existence of qualia, the existence of my current subjective experience is the only thing I know for certain, more certain by far than I can of the existence of the physical world. Whether I’m in the Matrix, or in a true flesh body, or if perhaps my consciousness is simulated by hordes of monks using abacci to simulate my neurons… whether reality itself is a lie… I can never place absolute certainty on those things.
But one thing I know for certain: I experience qualia, more certainly than 2+2=4.
No, I am not saying that qualia are something well-construed which does not exist, like a tea pot orbiting Mars, or like an aquatic dinosaur living today in a lake in Scotland. I am saying that the concept of qualia critically misconstrues the evidence. In fact your own statement here nicely illustrates what I take to be the reason the concept of qualia exists and persists, which is that by its very conception it provides the philosopher with something that he is supremely confident in. To employ my example: the philosopher does not know whether he is looking at an apple, or a plastic fake, or whether he is a brain in a vat hooked up to a computer simulation of an apple. What can he do to escape his uncertainty which grows with each new possible scenario that he imagines? Why, in the end it turns out to be simple: he declares that all these possibilities which he is unable to tell apart share a common element, and that element is a common subjective experience. Thus he turns his own failure (to tell things apart) into a supposed success (the supposed discovery of a common element). Voila: qualia. The concept is in effect defined to minimize uncertainty. So for you to write:
strongly confirms my own view about the nature of the philosopher’s concept of subjective experience, of qualia.
I always enjoy reading your contributions to these philosophy of mind debates, even when I disagree on some fairly minor points.
This is a rather Wittgensteinian diagnosis—it reminds me of Philosophical Investigations §308, for instance.
To play devil’s advocate I shall temporarily pretend to believe in qualia.
If I am unable to distinguish between visual stimuli A and B then some properties must be remaining the same each time, namely whatever it is that predisposes me to judge that present stimuli stand in such-and-such relations to other stimuli. (E.g. “this green thing, whatever it is, has a lighter, more garish shade than the leaves of that tree over there.”) Qualia are precisely those properties of my subjective experience which enable me to make these judgements. To be conscious of X at all implies the ability to synthesize X with other mental contents Y and make judgements like the comparison above. So since I am conscious, my mental contents must have qualia.
Therefore, I can no more doubt the existence of qualia than I can doubt the fact that I am conscious.
Not necessarily. Here’s what could be happening in your brain and which could underlie your power of discrimination: there is some operator which takes two inputs and produces an output “same” or “different”. Since this operator could, in principle, be anything at all, then it is in principle possible for any two arbitrary inputs to be assessed as “the same” by the comparison operator. They don’t have to have anything in common.
That’s in principle. In reality, we don’t expect brains to be so badly designed. We expect that under normal conditions (though not necessarily in highly artificial laboratory setups which test the limits of perception, such as for example “change blindness” experiments) the comparison operators which operate inside the brain output “the same” only when the two inputs are from objects in the real world which are really pretty similar in some important way. And in the case of an apple versus a fake plastic apple, there is something that does remain the same: the pattern of light traveling in the space between the object and your eyes.
But this common pattern of light is surely not a quale. It’s not even in the brain. In fact, the sameness of the two patterns can be demonstrated by taking a digital photo of each scene and then having software compare the two photos. Can you take a photo of a quale?
We have jumped from “some properties must be remaining the same”—which I’ve acknowledged is probably typically the case in normal circumstances—to “properties of my subjective experience”. So we’ve slipped in the term “subjective experience”.
Fine. I have evidence for qualia, but it is not certain. Does that change anything?