The Knowledge Argument

[NPC3001]

Since I've spent (way too) much time with Philosophy Of Mind literature, I'm quite familiar with the knowledge argument. I think it depends a bit on how you look at it. From an ontological perspective there's no need to resort to nonphysicalism. You could say, 'yes, red is something Mary can only learn when she actually sees it, but red still has a physical basis.'

The thing about philosophers, since the 20th century at least, is that they're terribly preoccupied with language and many of the things they argue over hinge on how we ought to speak about them. So I think part of the upshot of the knowledge argument is the idea that whatever physicalist language we apply to the world to explain the color red, it cannot account for the experience of red. In other words, we necessarily have to think of the world in not completely physicalist terms because there's an unsealable gap in between the language by which we explain red and the experience of it since we don't experience light working on our irises in a certain way or wavelengths projecting in a certain manner, we simply see RED.

Qualia is an interesting and frustrating subject in philosophy and while I respect the reasons people have in arguing for them, I'm not sure how truly successful they are in the end because of the obscurity of arguing for ineffibility of experience. People like Daniel Dennett have twisted this sort of thing against proponents for qualia.

[Paul C. Anagnostopoulos]

Originally Posted by David

Hmmm you seem to have concluded like me that this is a flawed gedanken experiment, but still want to reason using it

Huh? I'm just pointing out why it is flawed.

~~ Paul

[Paul C. Anagnostopoulos]

Originally Posted by NPC3001

The thing about philosophers, since the 20th century at least, is that they're terribly preoccupied with language and many of the things they argue over hinge on how we ought to speak about them. So I think part of the upshot of the knowledge argument is the idea that whatever physicalist language we apply to the world to explain the color red, it cannot account for the experience of red. In other words, we necessarily have to think of the world in not completely physicalist terms because there's an unsealable gap in between the language by which we explain red and the experience of it since we don't experience light working on our irises in a certain way or wavelengths projecting in a certain manner, we simply see RED.

I agree that it is difficult to think about the world in physicalist terms, but that is not a logical argument against physicalism. Philosophers might consider stopping the word game and having some patience.

Yeah, roight.

~~ Paul

[Interesting Ian]

Originally Posted by Paul C. Anagnostopoulos

One cannot acquire all possible information about color vision simply by reading about it. That is, assuming you really mean all possible information. There is nothing in the definition of physicalism that says that one can obtain all possible information about something by reading about it.

Physicalism holds that physics can, in principle, completely describe reality. Physics deals exclusively with the quantitative and therefore what in principle can be measured. Anything which can be measured is information.

So an appropriate book can in principle give us all possible information about colour vision. Mary just needs to be able to read and be intelligent enough to understand.

David Bailey

Hmmm you seem to have concluded like me that this is a flawed gedanken experiment, but still want to reason using it

Maybe someone can figure out a better version.

Well, if you like, just replace Mary with Android Mary. Mary's android brain is infinitely adaptable so that it can store all possible information about all things. Therefore, if physicalism is true, then Mary would know what it is like to experience green, an orgasm, love, pain and absolutely everything else just by reading about it.

[Paul C. Anagnostopoulos]

Originally Posted by Ian

Physicalism holds that physics can, in principle, completely describe reality. Physics deals exclusively with the quantitative and therefore what in principle can be measured. Anything which can be measured is information.

None of this implies that all the information stored in my brain state can be gained by reading. And it is patently obvious that it cannot.

So an appropriate book can in principle give us all possible information about colour vision. Mary just needs to be able to read and be intelligent enough to understand.

No, the book can only give us the subset of information that we call knowledge. It cannot put my brain into an arbitrary state. There is no bioelectrical connection between the book and my brain.

Well, if you like, just replace Mary with Android Mary. Mary's android brain is infinitely adaptable so that it can store all possible information about all things. Therefore, if physicalism is true, then Mary would know what it is like to experience green, an orgasm, love, pain and absolutely everything else just by reading about it.

Agreed, if Android Mary's brain can be put into an arbitrary state via some sort of programmable connection to the database about color vision. This is certainly not the case with human Mary.

There is information/data in my visual system, gained by actually seeing or an equivalent process, that cannot be placed there by reading, even if the reading completely describes the process.

~~ Paul

[DysonSphere]

Originally Posted by Paul C. Anagnostopoulos

None of this implies that all the information stored in my brain state can be gained by reading. And it is patently obvious that it cannot.
~~ Paul

It does in principle. All the facts about genes can be read about. All the facts about the brain can be read about as words or numbers. The question is if those words and numbers can express to a colorblind person what it is like to see the color red.

According to a physicalist the color blind scientist Mary can know what it is like to see the color red by studying the brain.

As a dualist I doubt this but I might be wrong. If physicalists can prove there claim then I have nothing to complain about.

[David Bailey]

Here is a slightly modified version of this gedanken experiment, which might get nearer to the point.

Suppose Mary is given the same black and white experience as before, except that she is allowed to play with coloured paper of the type that is given to pre-school kids (I always used to like that stuff).

Therefore she can experience colour, but not attach it to anything - somehow it is arranged that she still only sees her own body in black and white.

Now, when she finally sees the coloured world she gains a very precise piece of new knowledge - she learns which type of colour corresponds to which real-world object.

David

[Paul C. Anagnostopoulos]

Originally Posted by Dyson

It does in principle. All the facts about genes can be read about. All the facts about the brain can be read about as words or numbers. The question is if those words and numbers can express to a colorblind person what it is like to see the color red.

According to a physicalist the color blind scientist Mary can know what it is like to see the color red by studying the brain.

Where on Earth did people get this bizarre concept that Mary can know what it is like merely by reading? There is nothing in physicalism that says this. Mary can indeed obtain all the knowledge about color vision by reading. What she cannot do it obtain the brain state of a person who has seen color.

People do understand the difference between knowledge and brain state, yes?

~~ Paul

[Paul C. Anagnostopoulos]

Originally Posted by David

Suppose Mary is given the same black and white experience as before, except that she is allowed to play with coloured paper of the type that is given to pre-school kids (I always used to like that stuff).

Therefore she can experience colour, but not attach it to anything - somehow it is arranged that she still only sees her own body in black and white.

Now, when she finally sees the coloured world she gains a very precise piece of new knowledge - she learns which type of colour corresponds to which real-world object.

I think she could learn that correspondence by reading. She can memorize that leaves are green and the sky is blue. If playing with colored paper is enough to put her brain the same state as a normally sighted person, then I don't think she would have a new experience upon leaving the room.

~~ Paul

[David Bailey]

No - the only colour that Mary sees (before the great day) is the coloured paper, with no writing on it - or maybe just an anonymous code. So on her release she says things like "Now I know that paper colour 4512 was actually red, the colour I know from my studies is typical of ripe tomatoes and blood.

David