[QUOTE]Originally posted by robinrohan: [B]Language, as I define it, is the ability to create sentences. If you are able to take verbs and nouns and recombine them in ways you have not heard before, you have language.[/quote]
quote:Full consciousness and language are dependent on each other. You can't have one without the other.
I communicate in language, but don't think in it. I think, in fact that language shackles thought, slows it down.
Robinrohan, You pretty much got the gist of what Quetzal said, but your analogy is flawed.... Yes, I would suggest that the image, such as that of the beautiful woman you are using in your example, is physical. But it is a different physical than what you seem to be proposing.
Take your analogy to the TV... In a TV an exact scaled replica in 2D is emitted from the screen based off of an input hundreds of miles away.... Yes, in that case there are certain set things you can measure physically (such as a scaled height). However in the brain, the visual inputs of different wavelengths(e.g.colors) excite different neurons in the eye. The signals are sent via the optic nerve and other pathways until it hits the occipital lobe (at the back of the brain) Here the information is divided up even farther.
For instance, you are looking at a red cube in bright light. Well, the photoreceptors in your eye, specifically the cones that respond to red wavelengths are activated and send their info to the brain. If you were looking at another color, a different set of cones would be activated and in low light conditions an entirely different set of receptors, rods, would be activated. The information sent from the optic nerve from the receptors is topographically (spatially in relation to the neuron input) maintained on its way to the visual cortex (I am trying to drop the really specific stuff here to give you an overwiew). Approaching the visual cortex, visual information is processed to 'recognize' edges and at the occipital lobe its broken down into stimuli from right and left eyes, color and non color, and orientation (what direction the stimulus was in).
So you see, even when you look at a beautiful women (physically), there is no mini beautiful women hiding in your brain somewhere... just a collection of electrical impulses that your brain interprets from past experience. So when you are imagining a beautiful women, your brain is firing a lot of the same signals, and some from the hippocampus (the center for memory) in order to produce that image. But the imagined is never as concrete as the original .
Also, to help cement the idea that it is physical, like your TV analogy, certain physical aspects of a visual image, whether real or imagined can be measured through EMG (recording electrical signals from firing nerves), from experiments with PET scans, and the results from lesions in the brain. Place an electrode into a region of the brain and you can record signals, which correspond to sensory/motor input/output. You can also stimulate parts of the brain as well by applying an electrical signal, which will in turn cause a patient to feel what is not really happenning... maybe that their arm is moving etc....
quote:Great post, Quetzal. (Q: Thanks!) I also had a look at that first article you mention, and I think I grasp your idea. Let me summarize it to see if I do. Your point is that when we imagine an object or when we actually see an object, we are using the same brain-parts either way. Imagining is very like seeing, as far as the brain goes.
However, imagining is not like seeing for the eyes. The eyes are not used; however, the brain-parts that normally control vision are used. And so you conclude that both seeing and imagining are physical events.
Pretty much. However, I want to clarify that it’s not really the brain parts that control vision, rather the brain parts that process and integrate visual imagery that are activated.
Again, I apologize for the oversimplification, but for the purposes of this discussion, I think you’ve got it. Seeing something and imagining it are essentially the same thing – they use the same parts of the neocortex. The primary difference comes from processing input from external vs stored patterns. I think it’s significant (from the article) that there is apparently weaker activation when imagining a scene than when the scene is actually witnessed. This would be consistent with the idea that the brain doesn’t need to access all the neural networks responsible for seeing a new image – but is rather recall of memory and processing of a visual object class already stored in the brain.
quote:But have you forgotten my beautiful imaginary woman? What happened to her? Are you suggesting that image which I visualize is physical? If it were physical that image would be present in the brain. Couldn't we search the brain high and low and never find that image?
Not in so many words, no. What you are “seeing in your mind’s eye” as it were is an image presented to your visual cortex (or rather that portion of the brain that processes visual images) based on a representation created from coactivation of distributed patterns of neurons stored in discrete areas of the brain. In other words, your brain is making it up from whole cloth based on memorized patterns, stored emotional responses, semantics, stored perceptions (such as colors, sounds, etc). All of these neural impulses are brought together, melded/integrated, and presented as an image. She is not “physical”, in the sense that you can touch her. She IS “physical” in the sense that she is a pattern of neural impulses that can be measured – and in fact can be in some measure predicted.
Where the problems arise – to forestall the obvious objection here – is that it is (currently?) impossible determine the specific neurons in a specific individual that will generate the parts/patterns/etc that compose a mental image. Why? Simply because every single individual has a different set up when you get down to that scale.
quote:Let's use the following analogy. The brain is a tv set. I am watching a live football game. The figures I see on my screen are copies of the reality, the game being played live 100 miles away. The tv set football players are only copies of reality. Nonetheless they are physical copies. If I wanted to I could measure them physically, measure how tall they were, for example (of course they keep changing in size, depending on whether we have close-up shots or not, like the flickering imagination). So both the live game and the copy are physical. It strikes me that this is your description of the brain. Somewhere down in the brain is a physical image of my imaginary beautiful woman. It's not a mental image--it's a physical image. If I had a super brainscope I could measure how tall the image is, like I can measure the football players on the tv set.
Actually, that’s not a very good analogy. Look at it this way: the televised football game in your example is a representation of an actual event. A video copy of that football game is ALSO a representation of an actual event – and a fairly accurate one. There is a linear, one-to-one correlation between the object (the football game) and either the image on your screen or the video. However, the way your brain works is not like a video tape. I’m not sure how I can describe this without getting bogged down, so I’ll try another analogy (which is simplistic and collapses under its own weight as well fairly quickly, but is closer to the way I understand how the brain/memory/etc works).
The functioning of the brain is more akin to a distributed computer network with some odd programming. When this computer stores something in memory (say, a picture of a woman), it doesn’t store a complete woman-image. Rather, it breaks the image down into discrete patterns consisting of various attributes of the image (say, “arm” at one location, “mouth” at another, “face” at another, “beautiful” at several others, etc although it’s obviously more complicated and not as easily quantified as that). It also stores the linkage/association between the various patterns, so that you can retrieve the whole image if desired. However, the computer ALSO has the capability to select any given attribute and combine it with other attributes stored at different times and locations, and come up with a completely NEW image based on the parts. If this new image is “important” enough to the computer, then the associative linkage is stored for later retrieval – not the image itself. This is how you can “imagine” your beautiful, non-existent woman, and even recover and manipulate it later on. However, the “physical” existence of the image is in the linked neural networks that store the various attributes and associations. Where the analogy breaks down is that in the brain there is no functional differentiation between the “software” and “hardware”, unlike in a computer. They are indissoluable, not discrete – the brain’s software (patterns of neurons) and hardware (the neurons themselves and the tissues that form the brain) are for all practical purposes one and the same. You'll never be able to "measure" the image in your mind, because it doesn't actually exist as an image.
I hope I haven't just confused things more.
[edited to remove an exceptional number of "actuallys" ]
[This message has been edited by Quetzal, 11-21-2002]
quote:Originally posted by robinrohan: John, the only other possibility you've come up with is "spirit."
Care to say what spirit is if it's not mind?
Care to say what mind is if its not physical?
You are missing the point I'm trying to make. All that I can see you doing is asserting and reasserting your premises without defending them. It is getting a bit silly. Somewhere along the line you have decided that everything in mind, matter, or both and you are grossly glossing over anything that gets in the way.
The Egyptians subdivided the what you'd call mind into several components, for example.
quote:The rest of what you've said consists of positing that we can't know anything
... that we can't know reality actually. This is Kant. For Kant, what we perceive is reality filtered through mind. Concerning reality itself we have no information.
quote:or that we can only know phenomena
Which is not an option for what reasons? Seems to me that you just don't like the idea.
quote:or maybe possibly there's something else out there that we don't know about.
All life capable of space flight is human. True or false?
Very informative posts from both Obsidian and Quetzel.
Let me see if I got it:
When we see or when we imagine something, there is no actual duplica of that in the brain. A bunch of different signals are sent to the back of the brain and then sorted into classified groups. So the analogy would be more like digitizing a photo, except that there is no monitor to reproduce the picture. When we will ourselves to remember or imagine an image, then these different parts of the image are picked out of various files and brought together. But they are not really brought together. It just seems to us when we remember something or imagine something that they are. It seems like we are looking at a unified image, but that's an illusion. For one thing, we are not physically "looking." But even if we were physically looking, the situation would be the same. What appears to be a unified image is really separated into different compartments in the form of electical signals. quote from Obsidian: "The signals are sent via the optic nerve and other pathways until it hits the occipital lobe . . . . Here the information is divided up even farther."
However, I have this passage from Quetzal: "What you are 'seeing in your mind's eye' as it were is an image presented to your visual cortex." That sounds like there really is a unified image after all.
Is the visual cortex the monitor? This is where all the digitized parts of the image come together physically--whether we are seeing or imagining? That cannot be because there is no actual duplica in the brain of the image. What's in the visual cortex is still a bunch of electrical signals but "unified" in an electrical sense, not in a pictorial sense--but nonetheless physical.
But this illusion of the pictorial representation (whether looking or imagining)--what is this? It's not like a computer monitor--there's no illusion there--there really is a pictorial image produced; even though it is produced by digitized signals, it's still a physical image that can be measured as to height, etc.
So if I understand you correctly, I would suggest that it is this illusion of a pictorial image that is "mental"--not physical.
[This message has been edited by robinrohan, 11-21-2002]
You say I'm not defending my position. Well, here's a defense of one "alternative" you offer: Kant's 'phenomena.' You present that as an alternative, but 'phenomena' is another word for 'mental objects'. You haven't offered any different condition of reality. Why? Because there's none that are conceivable--unless you want to play the 'spirit' card. Your alternatives are just different names for the same thing.
Robinrohan, I wanted to add an addendum to my post above, the information that is sent to the occipital lobe is also sent to other areas of the brain for post processing to glean even more info from the data.... Anyway, back to the topic....
In terms of "'seeing in your mind's eye' as it were is an image presented to your visual cortex." I think the words 'presented to the visual cortex' are key here. Whether real or imagining your visual cortex recieves info about an image (not necessarily the unified image itself)from certain set neural networks, plus some added ones (the eyes or the hippocampus). This information is organized in different sections and your brain interprets the signals that it received based on past experience.
I don't think there is a 'monitor' in the brain. The brain, to me, is just one big sensory receiver and motor output device with some memory thrown in there that has internal circuitry to process all the info. You recognize something if you are looking at it, like a woman, based on certain characteristics... when you imagine a woman, your brain uses memory (coupled with alterations according to preference, hair color, weight etc) and the same pathways to 'fool' (although you are not really duping your brain) the brain into 'seeing' what you are imagining.
I would like to bring up additional points. The brain is NOT like a TV, deficits in the brain can produce deficits in the visual system and can affect what you can imagination. For instance, a color blind person (from birth)..... how would you describe the colors to them? Give me a definition of red... or yellow? The parts of the brain that are used for color processing are not present in color blind individuals. An image that you and an color blind individual see are not what is getting coded/received into the color blind persons brain the same way. Now I don't know if color blind people dream in color, (it would be an interesting experiment) but how could you test it? They couldn't describe the colors in their own dream, because there is no past experience. (They might be able to dream in color because of random firings of nerves, but I don't know really) And completely blind people (from birth) there is no 'image' at all, they use an entirely different set of sensory info to 'look' around their world. There would be no 'image' at all in that case.
Essentially the brain is a tool used to gather information about the world. Memory helps us to navigate safely around the world.... For instance, a person who has never seen a snake before(that includes books/internet) is bit by a snake. Before, if I asked that person what does a snake look like, they wouldn't know. But afterward, memory gives you a basis for what a snake is supposed to look like and your experience allows your imagination to modify that image (bigger fangs, creepy color). And it is impressed on you that snake=bite=bad, so you can avoid it in the future. So when you are out walking in the woods and you see one, you won't go up and try to pet it. The brain is geared up for our survival, it receives sensory info in order to derive relevant info to keep us alive. Imagination is a form of memory recall, which is key to our survival.
You are right, Obsidian. There is no monitor in the brain. It is purely a receiver and storer. Nonetheless we do have an inner monitor. It's the mind. Which means that there's a difference between the mind and the brain even though the mind can not exist without the brain (presumably.)
Those images we form when we imagine are purely mental. They exist in time but not in space. The pattern of electrical impulses in the cortex produces them, but they are not identical to them--in the same way that digitized photo information is not identical to the picture on the monitor.
I find this interesting because, personally, I am very poor at mental imagery.
I have a poor memory for details, including names and faces of people. It's not uncommon for someone to greet me by name, and I will not only not know their name, I very well might not even remember having met them before. In reading a book, often I loose essentially all recollection of the text just a few pages back. Such is also often the case, for message strings at .
With maybe very rare exceptions, I can not form visual images in my "minds eye". For example, I can stare intently at my pet cat. Then, when I close my eyes, the best image I can form it along the lines of a severely underexposed photograph. In general, it seems that the best longer term image recollections I can do, are more along the lines of being geometric discriptions.
When I wake up in the morning, it is relatively rare that I have any perception of having dreamed. Any dream visual imagery that I do recall, is vague and often rather abstract. What little imagery I do recall, is a foggy black and white.
I am curious about how others are, relative to me.
quote:Originally posted by robinrohan: You present that as an alternative, but 'phenomena' is another word for 'mental objects'.
Funny. I have not offered Kant's phenomena as an alternative. I offered Kant's noumena as such alternative. Kant doesn't divide between mental and physical but between phenomena and noumena. The former being mental object-ish, the latter being unknown. What we consider physical is a CONSTRUCT of the mind-- ie, it is phenomena. This is not the same division you have made between physical and mental.
quote:You haven't offered any different condition of reality.
I haven't offered any conditions meeting your preconcieved idea of what reality ought to be. This is different from not offering any different condition of reality. Virtually every major philosopher has a different conception of the conditions of reality. This is why these people have come to be considered major philosphers, imho.
quote:Your alternatives are just different names for the same thing.
That you wish to press things into one of three categories is precisely my objection.
Lets talk about atoms. The word first appeared among the Classic Greek philosphers. Is this the same as what is meant today? Nope. Not even close. Yet they both discuss the physical so they must be variations of the same thing? Nope. They are radically different concepts. Lumping them together does no justice to either. To the Greeks the atom was solid, an indivisible thing. Today, atoms are not solid at all but energy. Solidity is a the illusion produced by the interaction of electromagnetic forces.
Now take a peek at Berkeley's idealism, and compare it to Leibniz, also classed an idealist by some. The two concepts are as further apart than your mental and physical. Yet you class them the same? That's silly.
Now take Hume. Hume did the blatantly obvious and looked around. What he saw was perception. What he did not see was a 'physical'. Think about a dream. When you dream, you see things but these things are not physical things. Still, they are perceptions-- ie, colors, shapes, textures, whatever. This is what Hume saw when awake as well, and in fact, what I see. Hume, likewise, could find no causality. In fact, he found not much at all. Now for mind, look for it. More perceptions. Words that we call thoughts, images that we call memory, but no observer-- no mind. There must be something watching the show right? Well, if there is we ought to be able to find it. Hume could not. To my knowledge, there is no way out of this radical empiricism. There is no way to bootstrap yourself to any higher understanding. You have to assume your way out of it. (Kant's Prolegomena was an attempt to escape Hume's empiricism. Of course, he did so by assuming some things)
Platonic forms? From my Encyclopedia of Philosphy: "Neither a Platonic Form nor a shape is a mental entity." I don't believe that you will argue that a Form is a physical entity, and so therefore the Form is an option to your physical and mental.
quote:Originally posted by robinrohan: Ok, how about this:
I. Idealism 1a. Plato 1b. Kant 1c. Hinduism
II Dualism 2a. Descartes 2b. Christianity 2c. Islam
III Materialism 3a. Obsidian 3b. Quextal 3c. Bertrand Russell
[This message has been edited by robinrohan, 11-21-2002]
How about, that is all very nice but it isn't an argument?
How about, repetition isn't convincing?
How about, I quote from the EoP that Platonic Forms are not mental constructs and in the very next post you class Plato as an idealist?
How about, you are equivocating on your terms, especially those of idealism and materialism-- which have had many incarnations-- and this I suspect is why you are mixing and matching radically different concepts?
How about, you have ignored everything I have said about Hume?
How about, you have ignored everything I have said about Kant?
How about, you have ignored what I have said about Plato?
How about, you didn't respond to my points concerning the idea of atoms?
How about, you are lumping concepts into such broad classes that the division is meaningless?
Platonic forms are ideas in the mind of God. Mental or spiritual, whatever you prefer. These forms are not constructs but "essences." They are eternal and immutable. That's all I know about it.
I ignored Hume because Hume had no metaphysical philosophy. Hume studied epistemology, not metaphysics.
Kant phenomena--mental; noumena--God knows what.
You said that the word "atom" has different meanings for Ancient Greeks and moderns. No doubt. But not totally different. That's why we moderns took the name. They are little bitty something-or-others that make up the world of matter. Both Greeks and moderns believe that.
I like lumping and you like splitting. Both are necessary.
[This message has been edited by robinrohan, 11-21-2002]