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Author Topic:   My problem with evolution
Quetzal
Member (Idle past 4010 days)
Posts: 3228
Joined: 01-09-2002


Message 9 of 120 (23056)
11-18-2002 1:59 AM
Reply to: Message 6 by robinrohan
11-17-2002 4:57 PM


This is an interesting question. Before offering an answer, however, I'd like to ask you for your definition of two terms: "mind" and "spirit". You seem to be defining mind as "self-awareness". Is this correct? You have not, however, made a stab at defining what you mean by spirit. I'd appreciate a clarification.
This message is a reply to:
 Message 6 by robinrohan, posted 11-17-2002 4:57 PM robinrohan has responded

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 Message 15 by robinrohan, posted 11-18-2002 5:17 PM Quetzal has responded

  
Quetzal
Member (Idle past 4010 days)
Posts: 3228
Joined: 01-09-2002


Message 20 of 120 (23186)
11-19-2002 3:55 AM
Reply to: Message 15 by robinrohan
11-18-2002 5:17 PM


quote:
Quetzal, what I am saying is that "mind" and "spirit" are the same thing. We know what mind is--we've got one--but if spirit is something different, then there's no evidence that there is any such thing as spirit. "Mind" means self-awareness, the ability to imagine, the process of logic, memory--the usual qualities we associate with "mind."

Okay, I think you’re confusing a couple of concepts, here. Mind is much more than self-awareness. After all, there are numbers of other species – at least primates – that are self-aware. I don’t think you mean that. In addition, there are huge numbers of species that have memory – learned responses are quite common, which is one of the tests of memory. After all, how many bears do you see riding bicycles through the woods or seals balancing balls on their noses in the Arctic? These behaviors are taught them by (learned from) their trainers – and they remember them. Any time you see an organism that shows variation in behavior patterns based on learned behavior – for example “dialects” in songbirds based on paternal imprinting, or potato washing in Macaca fuscata - you are observing memory. From the standpoint of “logic”, or the cognitive ability to extrapolate relationships based on differential experience, chimpanzees show an ability to assess, plan, and form “strategic alliances” within a troop – which would indicate at least some form of abstract reasoning. They also have demonstrated the ability to “consider” optional behaviors before acting, another indicator of the ability to reason (although a case could be made that the observed behavior was equivocal). Obviously, unless you’re willing to postulate that all these organisms also have whatever you’re defining as “spirit”, then I’d say that that piece of your argument is falsified.

This is why I asked you for a definition of spirit. Is it a mental affect? Is it some intrinsic property of an organism (or even only humans)? How can you determine whether or not an organism that otherwise shows evidence of “mind” as you’ve defined it has a spirit?

quote:
Now mind is something quite different from the physical, or at least appears to be.

You’ll be hard pressed to show this is the case. Please provide a specific reference that supports your assertion. Or at least more of an explanation of how “mind” is non-physical.

quote:
Thoughts are no doubt events, but they are very peculiar events. For one thing, they are always "about" something. Objects are not "about" anything until a mind comes along and invests them with significance.

Hunh? I don’t follow you. Please clarify.

quote:
The only thing we know of that is not physical, the only other type of reality--is "mind." That is the only evidence of the spirit-world.

You have not shown that mind is non-physical, nor that it represents some “other type of reality”. If this is the only evidence of spirit, then without further explanation and evidence, I’d have to say that “spirit” doesn’t exist.


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Quetzal
Member (Idle past 4010 days)
Posts: 3228
Joined: 01-09-2002


Message 26 of 120 (23216)
11-19-2002 9:34 AM
Reply to: Message 22 by robinrohan
11-19-2002 8:24 AM


You're invoking several strawmen and/or misunderstandings of what I wrote. Please re-read the post to which you were responding, and be more careful in the future. You also failed completely to either answer my questions or object to any of my points. Try again.
quote:
About other species being self-aware. I have my doubts about that. Because an animal learns in rote fashion does not necessarily indicate self-awareness. But chimps might be self-aware in some primitive sense. There's no way to know for sure, since we can't get inside the head of a chimp.

You "may have doubts about" self awareness in other animals, but that merely shows you haven't read much recent literature on animal behavior. Mirror self-awareness (MSR) - probably one of the better objective tests - has been known in chimps for 30 years, and a number of recent studies have shown provocative results for bottlenose dolphins (Tursiops truncatus). Even human infants don't respond positively to MSR until about 18 mos-2 yrs of age. Moreover, studies using distorted mirrors with chimps show an ability for abstract reasoning - the importance here is that the distortion must be rationalized before self-recognition occurs, and the chimps tested showed this ability. The same ability to a lesser extent has been observed in MSR studies on gorillas and orangutans (as I said, higher primates...).

The bear/seal example shows not self awareness, as you would know if you read my post, but rather the operation of memory - which you stated was another quality that defines "mind".

quote:
In my view, higher animals have feelings but not thoughts. For example, if you leave your pet for awahile he will feel something--a lack. But he will not be consciously thinking, "Where is he? When is he going to come back?"

This is a complete non sequitor that has nothing to do with my post. In addition, you've now introduced two NEW terms that you're going to have to define: "thought" and "feeling". In any case, no one was talking about pets. My dog always greets me ecstatically when I come home from work (she's more demonstrative than my kids!), but I would in no way attribute her behavior to cognition, rather to an associative memory of daddy=pack leader {safety, food, petting, walkies, etc}.

Please respond substantively to my posts, thanks.

[This message has been edited by Quetzal, 11-19-2002]


This message is a reply to:
 Message 22 by robinrohan, posted 11-19-2002 8:24 AM robinrohan has responded

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 Message 27 by robinrohan, posted 11-19-2002 10:31 AM Quetzal has responded

  
Quetzal
Member (Idle past 4010 days)
Posts: 3228
Joined: 01-09-2002


Message 48 of 120 (23331)
11-20-2002 4:02 AM
Reply to: Message 27 by robinrohan
11-19-2002 10:31 AM


Okay, I think I’m starting to understand your question a bit better. Although I’m directly responding to this post for simplicity, I am basing my response also in part on your posts 37, 38, and 40. For those familiar with cognitive neuroscience, please forgive the gross oversimplification that follows.

One of the interesting things about the brain is its ability to select information from the environment, shape it, combine it with information from memory, and produce action, new memories, or “thoughts” as you’ve defined the term. Much of normal day-to-day “thinking” depends on environmental stimuli of one form or another triggering one or more of the functional, distinct neural networks in the brain that process such things as object recognition, movement recognition, auditory cues, etc (most of these are from various parts of the temporal cortex). Environment in this context can include internal state. The incoming signal is then processed/coordinated by the prefrontal cortex and parietal cortex (in humans), and an action, new neural linkage or physiological change is initiated. In essence, the brain acts to create a representation of the moment-to-moment environment through the linking of external cues, internal cues, and previously stored memory patterns. Since humans are primarily visual organisms, this representation is often a “visual” image. (Here’s an excellent, peer-reviewed on-line journal article from the “Journal of Cognitive Neuroscience” that explains it better than I can: Mental Imagery of Faces and Places Activates Corresponding Stimulus-Specific Brain Regions. The article also explains how your imagination of the lady from post #40 works.) Basically, the exact same regions of the brain are activated during processing of certain classes of external stimuli as are activated during imagination of those classes.

There is, in fact, no difference between “mind”, “thought” and “physical”. These terms are simply convenient labels for the neuroarchitecture of the brain and how it processes information. All thought is physical – it has no extrinsic reality outside the confines of the neural networks that are preferentially activated when the particular class of object you’re thinking about is processed. Imagining a beautiful woman is based on stored memories of: the class of object “women”, the learned social/semantic affect “beautiful”, and manipulation or modification of learned and pre-existing attributes (everything from object class “dress” to color perception to emotional lading). The fact that we “see” the mental image is simply the activation of the visual cortex in conjunction with the executive control function of the prefrontal cortex.

For those interested in current literature on the subject, here are a few interesting on-line journal articles from PNAS:

Emotion-induced changes in human medial prefrontal cortex: I. During cognitive task performance
Emotion-induced changes in human medial prefrontal cortex: II. During anticipatory anxiety
Medial prefrontal cortex and self-referential mental activity: Relation to a default mode of brain function
Integration of emotion and cognition in the lateral prefrontal cortex
A resource model of the neural basis of executive working memory (I think this one is pretty cool because it discusses actual functioning of the executive processor in pulling together other brain resources and memory to accomplish specific tasks).

I guess what all this boils down to robin, is that you don’t have “matter producing mental” – it’s all physical.


This message is a reply to:
 Message 27 by robinrohan, posted 11-19-2002 10:31 AM robinrohan has responded

Replies to this message:
 Message 55 by robinrohan, posted 11-20-2002 5:31 PM Quetzal has responded

  
Quetzal
Member (Idle past 4010 days)
Posts: 3228
Joined: 01-09-2002


Message 49 of 120 (23332)
11-20-2002 4:03 AM
Reply to: Message 47 by robinrohan
11-20-2002 1:22 AM


Don't feel bad robin, none of the rest of us understand Brad either.
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 Message 47 by robinrohan, posted 11-20-2002 1:22 AM robinrohan has not yet responded

  
Quetzal
Member (Idle past 4010 days)
Posts: 3228
Joined: 01-09-2002


Message 63 of 120 (23463)
11-21-2002 3:54 AM
Reply to: Message 55 by robinrohan
11-20-2002 5:31 PM


Hi robin: Thanks for your reply.

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]


This message is a reply to:
 Message 55 by robinrohan, posted 11-20-2002 5:31 PM robinrohan has not yet responded

  
Quetzal
Member (Idle past 4010 days)
Posts: 3228
Joined: 01-09-2002


Message 64 of 120 (23464)
11-21-2002 3:56 AM
Reply to: Message 62 by obsidian
11-21-2002 2:14 AM


Thanks Obsidian! I didn't see your reply before I posted the above. Great description.
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 Message 66 by robinrohan, posted 11-21-2002 9:00 AM Quetzal has not yet responded

  
Quetzal
Member (Idle past 4010 days)
Posts: 3228
Joined: 01-09-2002


Message 83 of 120 (23698)
11-22-2002 10:24 AM
Reply to: Message 70 by robinrohan
11-21-2002 12:03 PM


Hi robin,

Obsidian pretty much covered what I wanted to say. The only thing I would stress here is that mind and brain are basically just two descriptions of attributes of cognition - the result/output of differential coactivation of various neurons ("mind") and the neuroarchitecture that supports it ("brain"). I think you're pushing the dichotomy bit a little too hard, here. They are functionally indissoluable - mental images are affects, not effects (if that makes sense).


This message is a reply to:
 Message 70 by robinrohan, posted 11-21-2002 12:03 PM robinrohan has responded

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 Message 87 by robinrohan, posted 11-23-2002 11:59 AM Quetzal has responded

  
Quetzal
Member (Idle past 4010 days)
Posts: 3228
Joined: 01-09-2002


Message 105 of 120 (24155)
11-25-2002 3:11 AM
Reply to: Message 87 by robinrohan
11-23-2002 11:59 AM


quote:
But I'm beginning to think that pinning down the physical nature of a "mental" image involves us in an infinite regress. We have an illusion of an illusion of an illusion . . .

This may be a valid statement from a metaphysical sense, but from an empirical one there's really no problem. Just as Rationalist discussed how the brain processes incoming perception and memory, the "mental image" is merely an internally generated version of the same thing - except it doesn't rely on external cues. I'm not sure this can be considered an "illusion" except maybe in a philosophical sense (i.e., questions on the nature of reality and whether a mental or cognitive affect is "real"). It certainly has no extrinsic existence outside the brain. IMO, it is nonetheless real (because measurable) for all that.


This message is a reply to:
 Message 87 by robinrohan, posted 11-23-2002 11:59 AM robinrohan has responded

Replies to this message:
 Message 106 by robinrohan, posted 11-25-2002 4:42 PM Quetzal has not yet responded

  
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