What is the validity of reductionism in explaining mental properties?

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In summary, the conversation discusses the concept of physical reducibility of mental properties. It is argued that intentional and cognitive properties are reducible, but qualitative properties of consciousness, known as "qualia", are not. The idea of an explanatory gap between physical events and qualia is also discussed, with some arguing that there is a 1 to 1 correlation between the two, while others suggest a gap exists. The knowledge argument is brought up, which questions whether someone who knows everything about the physical world can truly understand the qualitative experience of that world without experiencing it themselves. The conversation concludes with the idea that there may be a supernatural element involved in the understanding of qualia.
  • #36
Q_Goest,

Don't you see the equations I presented? They are differential equations: completely deterministic.

I'm not suggesting the physical states are unknowable (in principle). My discussion was completely classical and deterministic. The physical systems are unknowable in practice because they are chaotic; you will never see two systems exhibit the same exact dynamics: too many variables.

I'm not sure what you mean by "the phsical states at any point in time are fixed" and then justify that from classical. Even classical problems require dynamical starting conditions for a unique solution.

A pendulum occupies the same position twice in one cycle, but you have to include the velocity for a unique solution. The velocity (in general) depends on how the position is changing with time. That requires looking back in time at more than one position.

You're used to seeing linear problems, which are a very special case, but the real world is nonlinear, so superposition fails and with it our intuition.
 
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  • #37
Q_Goest said:
If you're suggesting that the physical states are not knowable, just consider any computaional system (computer). The physical states at any point in time are fixed. There's no escaping that. Remember, we're talking about classical systems when talking about computationalism. Any deviations at the molecular level are averaged out - we don't care that there might be statistical deviations at the molecular level for classical physics.

Classical systems exist only in our minds. They are useful as we usually describe a system with few numbers. However the system is not adequately described with only few numbers. For example you may think that can of water can be described by pressure, volume, temperature, etc. But all that will not explain why water evaporates when it is at room temperature. You look at the can of water, you think you know everything that could be known about it and still the f***ing water evaporates. Oh, you think, there must be something supernatural about it, failing to recognize that some of the water molecules have the energy to escape and averaging the energy with a single number (the temperature) doesn't mean that they all behave the same.
 
  • #38
Upisoft said:
Well, the bonds, their energy and other properties still physically exist and we can call them "parts" even they are not the same type of parts as the particles themselves. The question is if there are genuine emergent properties that exist without physical "bonds" to explain them. Like quantum entanglement. There is no physical "bond" that can be measured. And if there is it will have to be FTL type of interaction. Or perhaps our knowledge is not good enough to grasp the real theory behind QM.

I understand. I mean it as a caveat. Sometimes we don't know all the parts; call it a "hidden parts" theory. Whenever we see all the parts don't "equal the sum" (however you really quantify that in the philosophical sense) it's something to consider before leaping to conclusions.

Btw, entanglement doesn't seem to work that way for me. it's reducible. The probability function of every particle is infinitely dispersed, it just gets really tiny far away from it's expectation value, so chance of interacting with other particles is small, but still realizable. That + Pauli exclusion principle seems to add up just fine to entanglement.
 
  • #39
Pythagorean said:
I'm not suggesting the physical states are unknowable (in principle). My discussion was completely classical and deterministic. The physical systems are unknowable in practice because they are chaotic; you will never see two systems exhibit the same exact dynamics: too many variables.

I'm not sure what you mean by "the phsical states at any point in time are fixed" and then justify that from classical. Even classical problems require dynamical starting conditions for a unique solution.
Ok, I misunderstood you. Perhaps you're saying that classical physics provides deterministic equations. Regardless, I think it's important to remember that computationalism doesn't require nonlinear systems, though it has been suggested (Alwyn Scott). A computer has fixed physical states at any point in time. There is nothing nonlinear about it and computationalism doesn't require nonlinear systems for conciousness to arise.

.. so superposition fails and with it our intuition.
Can you explain what you mean by "superposition fails"?
 
  • #40
As I've stated before, I am not intentionally a computationalist, and I feel like it's projected on me. I am not defending computationalism; I'm defending physicalism. I don't accept that physicalism always implies computationalism.

Superposition fails: F is a transformation (analogous to a computation I guess). x is the state before transform, y is after.

Now you have two states, x1 and x2

superposition states:

y1+y2 = F(x1) + F(x2) = F(x1 + x2)

not true in nonlinear systems:

F(x1+x2) != F(x1) + F(x2)

now bifurcations can happen: quantitative changes can change the qualitative picture. This is when scaling fails, for instance.
 
  • #41
Btw, every useful biophysical neuron model is nonlinear. It becomes a very high-dimensional nonlinear problem as you couple several neurons together, and they're excitable systems. They pretty much must exhibit chaos, or at least very interesting dynamics.
 
  • #42
Pythagorean,
You should read Alwyn Scott, "Reductionism Revisited" and also "On Quantum Theories of the Mind" for support of theories regarding the importance of classical, nonlinear systems for the mind. For a rebuttle, see Stapp, "On Quantum Theories of the Mind". They all address the issue of how nonlinear systems, both classical and QM, might be of importance to the mind.

I think the most important aspect of these nonlinear affects can be reduced to a fairly simple fact. Classical systems that are nonlinear are nevertheless separable but quantum mechanical systems are not. Consider, can a neuron that's been removed from the brain and put in a test of sorts (ex: a Petri dish) be subjected to all the same causal influences in principal, as it was subjected to while in the brain? If you can show in principal, why there are physical influences acting on the neuron in the brain that can't be duplicated in the Petri dish, then you can show the nonlinear affects in the brain are not separable. If that's true, then one can point to these nonlinear effects and claim they are somehow responsible for phenomenal experience.

Personally, I don't think it can be shown. See also Kronz and Tiehen, "Emergence and Quantum Mechanics" for more on the issue of separability and nonlinear systems. They basically conclude classical systems are separable but QM systems are not.
 
  • #43
Well, this gives me stuff to think about, I should get to bed for now; thanks for the discussion.
 
  • #44
Upisoft said:
You still have to define what does "deciphering currents" mean. Why only I have to explain? You do what you must do, then we can continue our conversation.



Yeah, what does "the mind deciphers the electrical currents(0's and 1's) which run on computer circuits and are output on monitors as Information" mean?? No, you are not getting an answer. It would also be a sort of insult to the forum if i did. While the internet is free for all, a rational discussion requires that you pay attention to the points being raised.

You asked what couldn't be explained by reductionistic logic and i gave you a few examples off the top of my head that you didn't address.

Here's some more:

What are the actual building blocks from which you are building everything UP? "Particles and fields" is only a very weak approximation and doesn't mean much of anything as far as our classical understanding is concerned. And do they behave deterministically?

Are YOU actually explaining anything or just describing what you see(through mathematical relationships)? Show me the reductionistic, physical basis for einselection that brings forth the universe and everything that we observe. Right now, using just the bottom-up appoach and without making a dozen likely unwarranted assumptions, it isn't possible to explain in sufficiently good detail the existence, interaction, motion and organization of anything. So your question - what can't be explained by studying the parts... and, especially since you put it in the philosophy forum, is rather puzzling.

I still think you didn't mean to derive 'insolvency', 'meditation', 'consciousness' and everything else that we observe from the number of electrons in an atom.
 
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  • #45
Maui said:
Yeah, what does "the mind deciphers the electrical currents(0's and 1's) which run on computer circuits and are output on monitors as Information" mean??
That means nothing. Where you get that stuff? Did I said it? Where?

Maui said:
No, you are not getting an answer. It would also be a sort of insult to the forum if i did.
Apparently asking for clarification and definition is an insult to this forum. Checking... Nope, you're incorrect.

Maui said:
While the internet is free for all, a rational discussion requires that you pay attention to the points being raised.
It is hard to guess what is your point when you deny important definition. Rational way to proceed was to ask for one.
 
  • #46
Pythagorean said:
I understand. I mean it as a caveat. Sometimes we don't know all the parts; call it a "hidden parts" theory. Whenever we see all the parts don't "equal the sum" (however you really quantify that in the philosophical sense) it's something to consider before leaping to conclusions.

Well, let's say we are unable to directly observe some of the hidden parts. Thus we will know about them only indirectly, by observing the emergent properties they create. If this happens to be true, does it mean the reductionism is not valid view?
 
  • #47
Q_Goest,

I will read your sources after this post.

The point is not that nonlinear dynamics is important for consciousness. The point is that the real world is nonlinear and it makes coupling things together very unintuitive. It actually adds more dimensions (literally) to the problem when you couple two such systems together.

In linear systems, if you couple two systems together, they can be reduced to the dimensions of one. There really are more dimensions, but you might as well just compute one and assume the other ones are directly dependent (which they will be in a purely theoretical problem in which you intend them to be, of course).

I think the most important aspect of these nonlinear affects can be reduced to a fairly simple fact. Classical systems that are nonlinear are nevertheless separable but quantum mechanical systems are not. Consider, can a neuron that's been removed from the brain and put in a test of sorts (ex: a Petri dish) be subjected to all the same causal influences in principal, as it was subjected to while in the brain? If you can show in principal, why there are physical influences acting on the neuron in the brain that can't be duplicated in the Petri dish, then you can show the nonlinear affects in the brain are not separable. If that's true, then one can point to these nonlinear effects and claim they are somehow responsible for phenomenal experience.

I'm not sure I get this argument. Neurons are very analogous to wave dynamics. One water molecule isn't wet: wave properties come from the coupling of water molecules through weak interactions (well, weaker than the ones that hold a single h20 molecule together).

You could, in principle, simulate 999,999 water molecules and put one real water molecule in your super chemistry lab and simulate wave mechanics. You just say "oh, let's add a term for coupling that describes the behavior we observe". Then you measure experiment vs. theory and you whittle your term (that represents the coupling) down so that there's less error between the two shapes (just like sculpting). We can eventually find how that coupling directly relates to the dynamic of a single cell in the network, but I wouldn't say that you can describe the coupling without talking about two cells.

But it's not intuitive. Each cell of the network is itself a network of something, which has been found to be a network of something, all the way down to the standard model. Will the particles of the standard model eventually turn out to be made up of networks of smaller particles?

You may be interested in the subject of http://en.wikipedia.org/wiki/Quantum_chaos" is not well understood in the case of chaos. It's not even really obvious to us how it could be, given the HUP vs. exponential sensitivity to initial conditions (and a lack of initial conditions all together in the probability wave function).

There's also always gravity.

But I must know, what's the basis for this argument:

if you can show in principal, why there are physical influences acting on the neuron in the brain that can't be duplicated in the Petri dish, then you can show the nonlinear affects in the brain are not separable. If that's true, then one can point to these nonlinear effects and claim they are somehow responsible for phenomenal experience.

This seems like a setup completely contrived to fail. One neuron doesn't describe the brain. It smells like a straw man to me, since the physicalist claim is that mental phenomena can be reduced to neurons and their interactions, not a neuron.

I don't understand what the physical influences acting on one neuron even has to do with the discussion besides to explain how it effects its neighboring neurons. That's kind of a warped view of reductionism.

Also, just to be clear, I'm (a), not (b):
reductionism said:
(a) an approach to understanding the nature of complex things by reducing them to the interactions of their parts, or to simpler or more fundamental things or (b) a philosophical position that a complex system is nothing but the sum of its parts, and that an account of it can be reduced to accounts of individual constituents

b) is shown to be false in nonlinear systems. I think most scientists, in fact, are a) and get b) projected onto them. Only in linear systems is b) true. Remember, again, that superposition does not hold anymore in nonlinear systems. This should send of a red flag for anyone using arguments about "the sum of its parts" because this is exactly a result of superposition holding, implying a linear system (F(x1+x2) = F(x1) + F(x2)).

Ok, I find your sources now and read.
 
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  • #48
Upisoft said:
Well, let's say we are unable to directly observe some of the hidden parts. Thus we will know about them only indirectly, by observing the emergent properties they create. If this happens to be true, does it mean the reductionism is not valid view?

See my post above (last quote) and tell me the definition of reductionism you're using.
 
  • #49
Q_Goest, Upisoft,

please also note that I am not an anti-integrationist. I believe reductionism and holism are equally valid. In fact, here's a paper loosely from my field:

from Analytical multi-scale method for multi-phase complex systems in process engineering—Bridging reductionism and holism
(lots of authors)

Chemical Engineering Science
Volume 62, Issue 13, July 2007, Pages 3346-3377

Multi-scale spatio-temporal structures, the dominant feature for all complex systems, are identified and discussed as a common challenge and frontier in process engineering, as well as in science and technology of many different fields and disciplines. Emphasis is paid to the correlation between different scales, which is one of the focuses in complexity science. The energy minimization multi-scale (EMMS) model for particle–fluid flow is revisited as an implementation of the analytical multi-scale method to elucidate its principles, in which the correlation between scales is established by analyzing the compromise between dominant mechanisms. This strategy has been extended to six other systems, covering single-phase flow, gas–liquid flow, granular flow and emulsions. A general framework of the method and the common feature of the compromise processes are then presented together with an introduction to some practical applications of the analytical multi-scale method and its extensions. We conclude with prospects on the multi-scale method as a reasonable approach to complex systems that bridges reductionism and holism.
 
  • #50
Pythagorean said:
See my post above (last quote) and tell me the definition of reductionism you're using.

I was thinking of definition (b). I see you use definition (a). I wonder then how this approach handles problems like black holes. Black holes cannot theoretically be studied other than an entity with few properties. Unless, of course, we find something faster than light, that can carry information. At least I think there is no other option.
 
  • #51
Upisoft said:
I was thinking of definition (b). I see you use definition (a). I wonder then how this approach handles problems like black holes. Black holes cannot theoretically be studied other than an entity with few properties. Unless, of course, we find something faster than light, that can carry information. At least I think there is no other option.

b) seems pretty indefensible to me. Physicalism is about scientific reductionism, not philosophical reductionism. The only difference is that "interactions" are included in a) because physics is all about interactions. We don't talk about the force between and electron and itself. Force is something that couples two different objects.

I don't know much about relativity or cosmology; my modern studies consisted of quantum and nonlinear. It might be a good question for the cosmology forum above that we could later link to for our discussion, but I would guess much of relativity reduces to spacetime.
 
  • #52
Upisoft said:
Well, let's say we are unable to directly observe some of the hidden parts. Thus we will know about them only indirectly, by observing the emergent properties they create. If this happens to be true, does it mean the reductionism is not valid view?

You can't apply reduction to strong emergent properties. But you can still have identity. This is the idea behind http://en.wikipedia.org/wiki/Anomalous_monism" .
 
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