Thursday, November 3, 2011

358: The Brain and back to the Identity Theory

What I tried in my previous lecture was to get hold of mental states by introducing introspection as a means to gain knowledge of our mental states.

The final result was that at the end of our discussion we had no idea what knowledge of our mental states we can obtain by introspection.

More important, there does not seem to be any part of the brain that functions as a monitor of those neurophysiological states that maintain and control conscious states.

There still is the belief that introspection gives us a special kind of knowledge about ourselves and our mental states and processes.

Then just hear this. In a normal population, Johansson and collaborators , a psychologist and researcher, manually displayed to participants pairs of pictures of women's faces.

On each trial, the participant was to point to the face he found more attractive. The picture of that face was then centered before the participant while the other face was hidden.

On some trials, participants were asked to explain the reasons for their choices while continuing to look at the selected face. On a few key trials, the experimenters used sleight-of-hand to present to the participant the face that was NOT selected as though it had been the face selected.

Strikingly, the switch was noticed only 28% of the time. What's more, when the change was not detected participants actually gave explanations for their choice that appealed to specific features of the unselected face that were not possessed by the selected face 13% of the time.

For example, one participant claimed to have chosen the face before him “because I love blondes” when in fact he had chosen a dark-haired face.

As you see, introspection is not really a reliable source of knowledge about our mental states. Yet, in their criticism of the identity theory, some philosophers still hold that introspection reveals something of the mind which neuroscience can not.

Thus, a number of authors have recently argued that a complete physical description of the universe inevitably leaves something out which introspection reveals, namely the qualitative nature of mental states.

There is something it is like to be a bat, for example, but any physical description of the bat’s brain, central nervous system, sensory equipment and so on, inevitably leaves this out.

This shows, it is argued, that a physical account of the bat is thus incomplete. Some have taken this to show that a proper account of the mind must inevitably appeal to something nonphysical.

I am still not inclined to agree with that idea and want to stick to the identity theory. Three principal types of identity theory have been proposed.

The first, associated with J.J.C. Smart (1920 - …), and sometimes called brain process materialism, is that sensations are identical with brain processes.

A second version, called central state materialism, and associated with David Armstrong (1926 - …), is that mental states are identical with states of the brain and central nervous system.

A third and more subtle version, offered by Herbert Feigl (1902 – 1988), is that certain neuro-physiological terms denote certain mental terms.

Following Frege's distinction (1848 - 1925) between sense and reference, Feigl argues that the terms differ in meaning, but their referents are the same.

This is similar to how the terms "morning star" and "evening star" both have different meanings, yet refer to the same object, namely venus.

So far, I stick to Feigl's approach. It is our language that creates our reality. And I think he has good arguments for his view.

Introspection….just take this statement: "I know that I am making a mistake…" The first "i" knows that the second "I" makes a mistake, while the second "I" believes he is doing fine….

It is a weird ability of the mind that it can double itself…. I am thinking about myself, who is thinking about a chess problem. The mind is fun…. ^_^

The Discussion

[13:20] herman Bergson: Thank you...
13:21] Mick Nerido: That is the issue the brain is thinking about itself...
[13:22] herman Bergson: Yes...that is why Auguste Comte said that introspection was nonsense…
[13:22] Clerisse Beeswing: the brain is a workaholic
[13:22] herman Bergson: that was 1830... ㋡
[13:22] Mick Nerido: Why nonsense?
[13:22] Binnie Fensen: How does dance fit into this model, then? As a choreographer, I work with the nonverbal.
[13:23] herman Bergson: The main point is since Descartes, that he believed that introspection showed infallible knowledge...
[13:24] herman Bergson: Well...lots of psychological experiments have already shown that that is not the case…
[13:24] herman Bergson: case
[13:24] Mick Nerido: It seem more like extremely personal knowledge, not objective reality
[13:25] herman Bergson: yes Mick....
[13:25] herman Bergson: and a lot can be explained by referring to memory
[13:25] Farv Hallison: I found lots of language fragments, many of which were wrong.
[13:26] Mick Nerido: Like intimacy is: into me see.
[13:27] herman Bergson: Well...introspection to get an insight in the working of the brain....not too reliable source of information..
[13:27] herman Bergson: For instance...they did an experiment..I'll save you the details...
[13:28] herman Bergson: the test persons had difficulty to solve the experimenter gave a marginal hint....
[13:28] herman Bergson: afterwards when asked...only a few mentioned the hint as the road to the solution
[13:28] Clerisse Beeswing: likw multiple choice
[13:28] Mick Nerido: Who said: We are what we think?
[13:29] herman Bergson: smile....
[13:29] herman Bergson: I know what I thing when I hear what I say, Mick ^_^
[13:29] herman Bergson: think
[13:29] Mick Nerido: lol
[13:30] herman Bergson: Ok then....
[13:30] herman Bergson: any questions or remarks left for today?
[13:30] herman Bergson: You are really gentle on me today ^_^
[13:31] Velvet (velvet.braham): what's the conclusion?
[13:31] Clerisse Beeswing: gosh you got me stomp
[13:31] Velvet (velvet.braham): that we leave stuff out when we remember?
[13:31] Velvet (velvet.braham): god knows I do :)
[13:31] Clerisse Beeswing: me too
[13:31] herman Bergson: the conclusion is that introspection is not a way to understand mental states
[13:31] Velvet (velvet.braham): that's logical
[13:32] herman Bergson: when we want to say that mental states are brain states, then introspection wont be of much help here
[13:32] Velvet (velvet.braham): but it's where we go first?
[13:32] Farv Hallison: not a way to probe brain states either.
[13:32] herman Bergson: We try to get hold of the mind....
[13:32] Clerisse Beeswing: my mind says find someone smarter
[13:33] Binnie Fensen: The mind constantly secretes thoughts. Impossible to get a hold of it.
[13:33] herman Bergson: We try to understand how a bunch of molecules of which we are composed, can give rise to what we call consciousness
[13:34] Velvet (velvet.braham): and now you've just dissolved the ground under me. thank you.
[13:34] :: Beertje :: (beertje.beaumont): welcome Lester
[13:34] Farv Hallison: consciousness is different from the mind.
[13:34] Binnie Fensen: Yes, what is the molecular structure of a thought?
[13:34] herman Bergson: nice question....Binnie
[13:35] Clerisse Beeswing: an idea
[13:35] :: Beertje :: (beertje.beaumont): can it be seen?
[13:35] Farv Hallison: there are folds and charged neutrons that can be coded to hold information.
[13:35] herman Bergson: It is the same structure as H2O molecules in a glass of water being liquid
[13:35] herman Bergson: what is the molecular structure of liquidity?
[13:36] Farv Hallison: water is an emergent property of water molecules.
[13:36] Clerisse Beeswing: space
[13:36] herman Bergson: Yes Farv…the emergence idea....we'll get to that certainly
[13:37] Lizzy Pleides: Don't we have self criticism, isn't introspection a precondition for that? and doesn't it help?
[13:37] CONNIE Eichel whispers: afk
[13:37] herman Bergson: Well Lizzy...introspection is a pretty weird ability
[13:37] Mick Nerido: So everything going on in our heads is electro chemical and obeys the laws of physics
[13:38] herman Bergson: theoretically you could say that Mick, yes
[13:38] herman Bergson: but this doesn't say much....
[13:38] Lizzy Pleides: to me that explanation is to easy Mick
[13:39] herman Bergson: you cant deduce consciousness from laws of physics
[13:39] Mick Nerido: It leaves out the old ides of "soul" or spirt
[13:39] herman Bergson: The big question is actually....
[13:40] herman Bergson: when everything just obeys the laws of physics…how can there be consciousness?
[13:40] Lizzy Pleides: true
[13:40] herman Bergson: all molecules and atoms in the universe are lifeless matter!
[13:40] Farv Hallison: quantum physics leaves room for free will.
[13:40] Binnie Fensen: Do we even know all the laws of physics?
[13:41] herman Bergson: Yes Farv...that is what Searle told in one of his lectures too..
[13:41] :: Beertje :: (beertje.beaumont): or the opposite of free will
[13:41] Farv Hallison: we know them at the size scale of rocks and mountains.
[13:42] Mick Nerido: an innate quality of matter my be to be able to evolve from unconscious to conscious states
[13:42] herman Bergson: "Do we even know all the laws of physics?"....a tempting question
[13:42] Lizzy Pleides: surely not
[13:42] herman Bergson: Just imagine what the question assumes...
[13:42] Binnie Fensen: Yes..
[13:42] herman Bergson: is there a finite or infinite set of laws of nature
[13:43] herman Bergson: How do we know how that set is composed...
[13:43] Farv Hallison: a few laws if you allow differential equations as laws.
[13:43] Binnie Fensen: We're looking for the laws of that's an interesting combination of words.
[13:43] herman Bergson: I am no mathematician Farv ^_^
[13:44] Mick Nerido: We all spring from the atoms of this planet and yet we are conscious…
[13:44] herman Bergson: Yes Binnie interesting and paradoxical indeed
[13:45] Lizzy Pleides: that prooves that there is more than atoms and molecules
[13:45] Farv Hallison: Gauge quantum field accounts for almost everything we can measure.
[13:45] Lester Buccaneer (lesterii): i must go, thanks for the lesson
[13:46] herman Bergson: Well, I think we have cracked our brains enough again for today...
[13:46] herman Bergson: So Lester....take a rest ^_^
[13:46] Lizzy Pleides: thank you Herman!
[13:46] Velvet (velvet.braham): thank you, professor!
[13:46] Mick Nerido: Thanks herman!
13:46] Binnie Fensen: thank you
[13:47] :: Beertje :: (beertje.beaumont): thank you professor:)
[13:47] herman Bergson: Class dismissed... ^_^
[13:47] Clerisse Beeswing: thank you professor..great class
[13:47] Farv Hallison: Thank you professor Bergson.
[13:48] herman Bergson: Hey Rodney!!!
[13:48] :: Beertje :: (beertje.beaumont): have a nice evening all:)

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