What is the Meaning of Phosphenes in Relation to Consciousness?

[selfAdjoint]

In the "place for Consciousness" reading forum, the following interchange took place between honestrosewater and hypnagogue:

With the phosphenes, I think it is well-known that they are representational of physical events taking place somewhere in the optic structures. Even imagined images can be correlated with specific brain events.

It depends on what we mean by representational. I think the sense of the word Rosenberg meant in chapter 1 is close to this one: "A state has a representational property when, to put it intuitively, it has a meaning or somehow stands in in some process for something else, such as an object, or a `proposition' ± a putative fact" (from http://people.cornell.edu/pages/beh24/rep.pdf ). One interpretation might further say that a qualitative experience Q is representational for a subject S if S takes Q to have some sort of meaning. It would seem to be safe to say that a visual experience as of a rock is representational for all cognitively normal, non-infant humans: we take such an experience to mean that there is a rock in the external world, sitting in front of us. But for a person who is not particularly educated about physics or physiology and does not hold supernatural beliefs, the experience of phosphenes probably has no particular meaning; it's just an experience, and not indicative of anything beyond itself. For such a person, phosphenes are not representational, as the word is defined above.

But whether we assign some extrinsic meaning to them based on our education in physiology or whatevee, phosphenes are just physical events without intrinsic meaning, and they don't meet hypnagogue's quoted criterion of standing for anything. The same can be said of trying to think of "abstract redness" and other such excercises. Even if you can do it, what is gained for the definition of consciousness as apart from and richer than physical processes?

 

[Canute]

As far as I can tell phosphenes, inasmuch as we are consciously aware of them, must be qualia. My dictionary states that 'quale' is a near-synonym for 'percept' and, as experienced, phosphenes are percepts. I'm not sure what representation has to do with anything (I wasn't sure in the original discussion). I don't think a quale has to represent anything, it is what it is. The trouble is that the term 'quale', as usual, gets used in different ways.

You seem to be saying that phosphenes do not represent anything and therefore that they are physical events. I can't follow that. Is this what you are saying?

 

[hypnagogue]

In the "place for Consciousness" reading forum, the following interchange took place between honestrosewater and hypnagogue:

Actually, the quoted text here is from loseyourname, not honestrosewater.

But whether we assign some extrinsic meaning to them based on our education in physiology or whatevee, phosphenes are just physical events without intrinsic meaning, and they don't meet hypnagogue's quoted criterion of standing for anything.

I'm not sure what you mean by intrinsic and extrinsic meaning. But yes, I argued that on some interpretations of what "representational" means, phosphenes are not representational. That doesn't imply that they're not qualia, though.

Even if you can do it, what is gained for the definition of consciousness as apart from and richer than physical processes?

You make it sound here as if it's somewhat of an arbitrary decision to think about p-consciousness this way, and we can just as well consider it to be physical if that suits our needs better. But in the context of Rosenberg's argument, with respect to thinking about qualia and physical processes, we're not making some arbitrary decision to define consciousness as apart from (i.e. not entailed by) and richer than (i.e. containing qualitative content) physical processes. Rather, the idea is that this depiction of p-consciousness is what logically follows from observation of qualia and from what it means to be physical. So the relevant question wouldn't be "what is to be gained," as much as it would be "what do we do now that this theoretical schism has been forced on us?"

Of course, one can choose to argue that it really isn't forced upon us by attempting to counter Rosenberg's arguments. But asking what is to be gained from it seems to indicate a misunderstanding of what is being claimed.

 

[selfAdjoint]

Sorry about the name mixup. At least I got yours right!

The point I was making was that the book asserts that p-consciousness events are richer than physical ones because they have content. But phosphenes, adduced as an example of this, don't have any content, except the experiencer's memories of things he has learned about phosphenes or "bare difference" comparisons of these phosphenes with remembered ones.

Maybe I'm flogging a dead horse, but if I am, why did he bring up phosphenes at all, and what would he replace them with?

 

[hypnagogue]

Sorry about the name mixup. At least I got yours right!

No problem, I'm not the best with names myself.

The point I was making was that the book asserts that p-consciousness events are richer than physical ones because they have content. But phosphenes, adduced as an example of this, don't have any content, except the experiencer's memories of things he has learned about phosphenes or "bare difference" comparisons of these phosphenes with remembered ones.

The claim is that p-conscious events have qualitative content. Phosphenes straightforwardly do have qualitative content; it is like something to experience phosphenes. (If you want to define "phosphene" as just the relevant physical processes taking place in the eye/brain, then we can say that the subjective experience that normally co-occurs with phosphenes has qualitative content; that's a terminological point that might be a source of some confusion.)

It is arguable that phosphenes don't have representational content, but representational content is not identical to qualitative content.

To pre-empt any potential confusion, it might be worth mentioning that representational content does not present the same philosophical problems as qualitative content. Rosenberg argues that qualitative content can't be entailed by bare difference, but I don't believe there is anything problematic about presuming that representational content can be entailed by bare difference. Even though they are both called contents, "qualitative content" seems to refer to intrinsic properties whereas "representational content" seems to refer to relational properties. Similarly, when it is said that physical ontology has no 'content,' it is meant that physical ontology has no intrinsic properties, not that physical properties can't be representational.

Maybe I'm flogging a dead horse, but if I am, why did he bring up phosphenes at all, and what would he replace them with?

Rosenberg brings up phosphenes (briefly, in a couple of sentences of the first chapter) to help the reader isolate what is meant by phenomenal consciousness/subjective experience. Specifically, he uses them to illustrate that qualia are not necessarily representational; here we have something that is clearly a quale, but is arguably not representational.

I'm not sure what you mean when you ask what he would replace them with. There's nothing he says about phosphenes that has anything to do with replacement; he just mentions them briefly to help the reader understand what is meant by a term.

 

[honestrosewater]

I've been waiting for an opportunity to bring this up.

A classic example of the use-mention confusion in paintings is the occurence of a palette in a painting. Whereas the palette is an illusion created by the representational skill of the painter, the paints on the painted palette are literal daubs of paint from the artist's palette. The paint plays itself- it does not symbolize anything else.

What if Rosenberg used this example instead of phospenes? Such a painting has both representational (an artist's palette) and nonrepresentational (literal daubs of paint) aspects. Additionally, the paints on the painted artist's palette seem to blur the representational and nonrepresentational aspects; The representation contains, in some way, the nonrepresentational aspects, and this seems to make those aspects representational. And the "nonrepresentation" contains, in some way, the representational aspects, but I don't think this makes those aspects nonrepresentational. Clarifying in what way they contain each other would be most helpful.

 

[Les Sleeth]

The point I was making was that the book asserts that p-consciousness events are richer than physical ones because they have content. But phosphenes, adduced as an example of this, don't have any content, except the experiencer's memories of things he has learned about phosphenes or "bare difference" comparisons of these phosphenes with remembered ones.

I can't see any difference it makes what the source is of something that stimulates experience. Sense data could stimulate it, or retina auto-excitation, or neurons firing from malfunction, or imagination, or hallucination . . . if consciousness can experience them they qualify as quale (i.e., you can know "what it's like" to experience phophenes, etc.). It seems like the orignial point was that qualia is a different issue from the stimulating event itself (whether it is physical, representational, delusional or whatever).