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Religion and Ethics Discussion => Philosophy, in all its guises. => Topic started by: Free Willy on February 17, 2023, 03:37:00 PM

Title: Reductionism vs. Emergence
Post by: Free Willy on February 17, 2023, 03:37:00 PM
This article on Reductionism vs Emergence has, er, emerged.

https://bigthink.com/13-8/reductionism-vs-emergence-science-philosophy/
Title: Re: Reductionism vs. Emergence
Post by: bluehillside Retd. on February 17, 2023, 04:53:14 PM
Vlad,

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This article on Reductionism vs Emergence has, er, emerged.

https://bigthink.com/13-8/reductionism-vs-emergence-science-philosophy/

And here's a rebuttal:

https://bigthink.com/starts-with-a-bang/universe-reductionist/
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 17, 2023, 05:31:27 PM
Vlad,

And here's a rebuttal:

https://bigthink.com/starts-with-a-bang/universe-reductionist/
Tried to find at least some sketchy explanatory chain from physics to sociology and art but alas he never got beyond er, physics and when he did get out of physics into biology it was a very physical biology. I wouldn't be surprised if eliminationists were round this like flies around the proverbial.

Alas the whole piece emerges as another case of someone who thinks that what he does for a living with how the world is.

Emergence fails for him seemingly because and solely because it isn't reductionism.

He cannot forgive emergentists for not knowing how emergence works but is quick to absolve reductionists for not knowing the same things with an added promissory note that they are sure to if only they have the right gear.
Title: Re: Reductionism vs. Emergence
Post by: bluehillside Retd. on February 17, 2023, 05:55:10 PM
Vlad,

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Tried to find at least some sketchy explanatory chain from physics to sociology and art but alas he never got beyond er, physics and when he did get out of physics into biology it was a very physical biology. I wouldn't be surprised if eliminationists were round this like flies around the proverbial.

Alas the whole piece emerges as another case of someone who thinks that what he does for a living with how the world is.

Emergence fails for him seemingly because and solely because it isn't reductionism.

He cannot forgive emergentists for not knowing how emergence works but is quick to absolve reductionists for not knowing the same things with an added promissory note that they are sure to if only they have the right gear.

As with so much else, you have this wrong. The “emergentist” claim is: “You, your dog, and the specifics of your person-dog affection could not be predicted, even in principle, even from perfect knowledge of all your elementary particles”. The problem with that bold claim that Ethan Siegel sets out is that there’s no justifying argument to support it. That is, why given both perfect knowledge of the initial conditions and sufficiently massive computing power could all that not be predicted?

The rest of your effort is just your standard ad hom ascribing of dodgy motives for no apparent reason.     
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 17, 2023, 06:09:33 PM
Vlad,

As with so much else, you have this wrong. The “emergentist” claim is: “You, your dog, and the specifics of your person-dog affection could not be predicted, even in principle, even from perfect knowledge of all your elementary particles”. The problem with that bold claim that Ethan Siegel sets out is that there’s no justifying argument to support it. That is, why given both perfect knowledge of the initial conditions and sufficiently massive computing power could all that not be predicted?

The rest of your effort is just your standard ad hom ascribing of dodgy motives for no apparent reason.     
It certainly wasn't an ad hom Hillside. That comes now. By only talking about physics he was taking the piss. Was it this that attracted you to this article?
Title: Re: Reductionism vs. Emergence
Post by: bluehillside Retd. on February 17, 2023, 06:16:04 PM
Vlad,

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It certainly wasn't an ad hom Hillside. That comes now. By only talking about physics he was taking the piss. Was it this that attracted you to this article?

Evasion noted. He actually explained why "just" physics is the default, and that the burden of proof is thus with the "emergentist" to explain why it's not. Burden of proof is something that's always foxed you, but even you should be able to grasp the point here surely? 
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 18, 2023, 07:44:08 AM
Vlad,

Evasion noted. He actually explained why "just" physics is the default, and that the burden of proof is thus with the "emergentist" to explain why it's not. Burden of proof is something that's always foxed you, but even you should be able to grasp the point here surely?
Firstly there is his claim of fundamental laws and then what he calls additional laws. The assertion here is there can be no more fundamental laws and that we know them all.
Secondly his attitude to what he calls qualitative novel properties is one that they are illusory. This is eliminationist and that is not an established position.
Since he has not established reducibility as universal rather than a technique in science I don't see how he can have the default position.
Title: Re: Reductionism vs. Emergence
Post by: bluehillside Retd. on February 18, 2023, 05:10:50 PM
Vlad,

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Firstly there is his claim of fundamental laws and then what he calls additional laws. The assertion here is there can be no more fundamental laws and that we know them all.

No it isn’t. If you think he asserts that nonetheless though, then just quote that part.

Clue: you won’t be able to.   

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Secondly his attitude to what he calls qualitative novel properties is one that they are illusory. This is eliminationist and that is not an established position.

Again, tell us where he does that and, once you’ve done so, explain why it’s “eliminationist” not to accept as real that which hasn’t been demonstrated to be real?

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Since he has not established reducibility as universal rather than a technique in science I don't see how he can have the default position.

Presumably that’s because you don’t understand the term “default”? You don’t have to demonstrate universality to have a default position. Try to understand why this is.
Title: Re: Reductionism vs. Emergence
Post by: Outrider on February 20, 2023, 10:32:56 AM
It certainly wasn't an ad hom Hillside. That comes now. By only talking about physics he was taking the piss. Was it this that attracted you to this article?

Given that biology is just applied chemistry, and chemistry is just applied physics, I can see his stance, but I agree with you that to just think of the physics is fundamentally flawed.

Physics, after all, is just applied maths.

O.
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 20, 2023, 12:10:48 PM
Given that biology is just applied chemistry, and chemistry is just applied physics, I can see his stance,
Yes, Eliminationist
Quote
but I agree with you that to just think of the physics is fundamentally flawed.

Physics, after all, is just applied maths.
I did hear somewhere that Maths was shorthand for philosophy...
Title: Re: Reductionism vs. Emergence
Post by: bluehillside Retd. on February 20, 2023, 12:20:00 PM
Vlad,

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Yes, Eliminationist

No. The claim is that, even with perfect knowledge of the starting conditions and unlimited computing power, the emergent phenomena would be impossible to predict even in principle (“You, your dog, and the specifics of your person-dog affection could not be predicted, even in principle, even from perfect knowledge of all your elementary particles”).

So far as I can see there’s no argument to justify that claim but that’s what it is nonetheless.

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I did hear somewhere that Maths was shorthand for philosophy...

Perhaps you did, but it’s irrelevant – your mistake was to think that a default position requires a universal application (“…since he has not established reducibility as universal”) rather than its actual meaning of a holding position pending any further information that may invalidate or amend it. 
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 20, 2023, 02:52:03 PM
Vlad,

No. The claim is that, even with perfect knowledge of the starting conditions and unlimited computing power, the emergent phenomena would be impossible to predict even in principle (“You, your dog, and the specifics of your person-dog affection could not be predicted, even in principle, even from perfect knowledge of all your elementary particles”).
That seems a most complex rendering of a ''claim''. You might be the only one making that on behalf of people like myself. If the fundamentals are basically units that can join together we can predict there will be large number complex arrangements of units and that's about it. we may speculate that these may become repeating or chaotic but I don't see this predicting anything more. Thus anything more than this would have to be eliminatively reduced to what I've previously said for your contention to work.

Chomsky observed that the pure sciences become less useful when we move into areas such as sociology, psychology and anthropology. Is the language of say, physics sufficient for ecology or ethology? I would say not.
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So far as I can see there’s no argument to justify that claim but that’s what it is nonetheless.
I don't know who is making that exact claim.

Does the claim of reductionism here match other default position claims you have made? I would say not since those have been made in the context of empirical or sense data, here empirical sense such as say wetness seems to be dismissed as at worst illusion and at best merely sensing forces between particles and being somehow hoodwinked by qualia. So it is difficult to justify reductionist here as any kind of default position. Also can you call a philosophy a default position? I'm not sure you can.

Title: Re: Reductionism vs. Emergence
Post by: bluehillside Retd. on February 20, 2023, 03:14:29 PM
Vlad,

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That seems a most complex rendering of a ''claim''.

As I quoted its author verbatim you might want to take that up with him.

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You might be the only one making that on behalf of people like myself.

What are you trying to say here? I merely told you what the claim was, and quoted it from the article. 

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If the fundamentals are basically units that can join together we can predict there will be large number complex arrangements of units and that's about it. we may speculate that these may become repeating or chaotic but I don't see this predicting anything more. Thus anything more than this would have to be eliminatively reduced to what I've previously said for your contention to work.

Try to focus there – the claim is: “You, your dog, and the specifics of your person-dog affection could not be predicted, even in principle, even from perfect knowledge of all your elementary particles”. Assuming unlimited computing power too, can you see any justification for it? I can’t.

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Chomsky observed that the pure sciences become less useful when we move into areas such as sociology, psychology and anthropology. Is the language of say, physics sufficient for ecology or ethology? I would say not.

Relevance? We’re talking about a claim made even in principle here remember, not in practice.

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I don't know who is making that exact claim.

The author of the article you posted a link to in your OP.

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Does the claim of reductionism here match other default position claims you have made? I would say not since those have been made in the context of empirical or sense data, here empirical sense such as say wetness seems to be dismissed as at worst illusion and at best merely sensing forces between particles and being somehow hoodwinked by qualia. So it is difficult to justify reductionist here as any kind of default position. Also can you call a philosophy a default position? I'm not sure you can.

You’ve collapsed into gibberish again here. The “default position” (ie, “reductionism" to an empirical model are least in principle) is the default position because the only knowledge hitherto we’ve verifiably and usefully obtained is empirical in character. Thus we start with that model pending any information or method that might invalidate it.

And that’s why what the author calls reductionism should be the default position.       
Title: Re: Reductionism vs. Emergence
Post by: Outrider on February 20, 2023, 03:16:31 PM
If the fundamentals are basically units that can join together we can predict there will be large number complex arrangements of units and that's about it.

No, we can accurately predict interactions between a small number of particles. The interactions themselves do not become more complex in larger systems, there are simply a vast number of them to be considered. The problem isn't one of understanding when one tries to scale up to macroscopic effects, but rather one of scale.

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we may speculate that these may become repeating or chaotic but I don't see this predicting anything more.

And yet we have increasingly accurate models for any number of phenomena, from air-flow over formula 1 aerofoils to population growth of bacteria in various media.

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Chomsky observed that the pure sciences become less useful when we move into areas such as sociology, psychology and anthropology. Is the language of say, physics sufficient for ecology or ethology? I would say not.  I don't know who is making that exact claim.

It is an unfortunate aspect of reality that it's really, really hard to find perfectly spherical chickens which do not evince wind resistance in order to conduct experiments in ideal conditions... Is the language of physics sufficient for ecology, no, because the language of ecology takes inherent short-cuts so as not to have to account for the innumerable individual sub-atomic interactions. A sufficiently large computer with an appropriate dataset, however, could accurately plot activity so that you could describe in ecological language the exact future of any given piece of land, sea or atmosphere.

O.
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 20, 2023, 07:17:37 PM
No, we can accurately predict interactions between a small number of particles. The interactions themselves do not become more complex in larger systems, there are simply a vast number of them to be considered. The problem isn't one of understanding when one tries to scale up to macroscopic effects, but rather one of scale.

And yet we have increasingly accurate models for any number of phenomena, from air-flow over formula 1 aerofoils to population growth of bacteria in various media.

It is an unfortunate aspect of reality that it's really, really hard to find perfectly spherical chickens which do not evince wind resistance in order to conduct experiments in ideal conditions... Is the language of physics sufficient for ecology, no, because the language of ecology takes inherent short-cuts so as not to have to account for the innumerable individual sub-atomic interactions. A sufficiently large computer with an appropriate dataset, however, could accurately plot activity so that you could describe in ecological language the exact future of any given piece of land, sea or atmosphere.

O.
Yes, geological modelling sounds the ideal job for a supercomputer but I wonder if we take chaotic events into consideration. Predicting chaos though doesn't sound like predicting everything. how do you handle chaos in aerodynamics?
Title: Re: Reductionism vs. Emergence
Post by: jeremyp on February 20, 2023, 07:35:00 PM
This article on Reductionism vs Emergence has, er, emerged.

https://bigthink.com/13-8/reductionism-vs-emergence-science-philosophy/

Yeah. It's nonsense.

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A phenomenon is emergent if it cannot be reduced to, explained or predicted from its constituent parts… emergent phenomena arise out of lower-level entities, but they cannot be reduced to, explained nor predicted from their micro-level base

This is saying that the laws of physics are wrong. It's obviously bollocks.
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 20, 2023, 08:38:43 PM
Yeah. It's nonsense.

This is saying that the laws of physics are wrong. It's obviously bollocks.
How does it say the laws of physics are wrong? The author is a physicist isn't he?
Title: Re: Reductionism vs. Emergence
Post by: Outrider on February 20, 2023, 11:07:26 PM
Yes, geological modelling sounds the ideal job for a supercomputer but I wonder if we take chaotic events into consideration. Predicting chaos though doesn't sound like predicting everything. how do you handle chaos in aerodynamics?

With more processing power and more accurate start data.

The problem with modelling chaos is insufficient capacity, it's different to randomness. Genuine randomness is difficult for a computer to simulate, you typically need some form of analogue input to provide the randomness, and even then by its nature that limits the effectiveness of any prediction or modelling. Chaos, though is about the instability of a system, how quickly and significantly small changes to input variables can result in a change. That's not difficult in principle for a computer to model because chaos is still a product of an absolutely deterministic system, it's just a product of a deterministic system which is volatile.

That can be difficult to model, but isn't always.

O.
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 21, 2023, 08:35:35 AM
With more processing power and more accurate start data.

The problem with modelling chaos is insufficient capacity, it's different to randomness. Genuine randomness is difficult for a computer to simulate, you typically need some form of analogue input to provide the randomness, and even then by its nature that limits the effectiveness of any prediction or modelling. Chaos, though is about the instability of a system, how quickly and significantly small changes to input variables can result in a change. That's not difficult in principle for a computer to model because chaos is still a product of an absolutely deterministic system, it's just a product of a deterministic system which is volatile.

That can be difficult to model, but isn't always.

O.
Thanks for that. I did hear that chaos was not the same as random.
I still wonder, since we are dealing at the molecular and particulate level whether terms like complexity, order and disorder equate to the term emergent or whether the term emergent is, effectively, redundant.
Title: Re: Reductionism vs. Emergence
Post by: Outrider on February 21, 2023, 08:44:10 AM
Thanks for that. I did hear that chaos was not the same as random.
I still wonder, since we are dealing at the molecular and particulate level whether terms like complexity, order and disorder equate to the term emergent or whether the term emergent is, effectively, redundant.

In my experience, and there might be a more technical use of it that I'm not familiar with, it tends to be used when a system elicits a behaviour or function which wasn't the original 'point'. In design terms, for instance, and emergent property of hard drives turned out to be that you could use them as musical instruments - they weren't designed to do that, the production of noise was a result of manufacturing imperfections and the physical reality of not being able to produce a frictionless surface, but once that noise was there it could be modulated.

In evolutionary terms its used when there's no obvious evolutionary purpose for a particular trait, but it can be linked to a potentially useful trait that either observed or was possible. Unfortunately with the lack of so much of the detailed evidence for each evolutionary tree, there's an awful lot of supposition to try and fill the gaps.

O.
Title: Re: Reductionism vs. Emergence
Post by: Stranger on February 21, 2023, 09:33:45 AM
In my experience, and there might be a more technical use of it that I'm not familiar with...

Probably one of the simplest ways to define emergence is something like what Wiki says:-

"In philosophy, systems theory, science, and art, emergence occurs when an entity is observed to have properties its parts do not have on their own, properties or behaviors that emerge only when the parts interact in a wider whole."
-- Emergence (https://en.wikipedia.org/wiki/Emergence)
Title: Re: Reductionism vs. Emergence
Post by: Stranger on February 21, 2023, 10:04:43 AM
Just to add, probably one of the most striking examples is how chemistry emerges from physics because we can actually do the maths for it, starting from quantum mechanics and ending up with a model of an atom that can explain its chemical properties (although it's horrendously complicated even for a simple hydrogen atom). It's also interesting that there are some macro level behaviours that chemistry can't deal with and we have to go back to quantum mechanics - semiconductors, for example.
Title: Re: Reductionism vs. Emergence
Post by: jeremyp on February 21, 2023, 12:38:44 PM
How does it say the laws of physics are wrong? The author is a physicist isn't he?

Because, if you can't reduce emergent behaviour in terms of the fundamental particles that it is made of, it means the fundamental particles are not behaving within the laws of physics.
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 21, 2023, 03:02:33 PM
Because, if you can't reduce emergent behaviour in terms of the fundamental particles that it is made of, it means the fundamental particles are not behaving within the laws of physics.
They can be working fine within the laws of Physics without describing the tax arrangements of the principality of Leichtenstein in any meaningful way.
Title: Re: Reductionism vs. Emergence
Post by: bluehillside Retd. on February 21, 2023, 03:05:59 PM
Vlad,

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They can be working fine within the laws of Physics without describing the tax arrangements of the principality of Leichtenstein in any meaningful way.

Why do you think that's true even in principle (which is the claim)?
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 21, 2023, 04:33:27 PM
Vlad,

Why do you think that's true even in principle (which is the claim)?
Why do I think fundamental particles follow the laws of physics without reference to tax arrangements in Leichtenstein?
Er, because of the laws of physics.

Tax arrangements are an emergent from particles which don't have tax arrangements.
Title: Re: Reductionism vs. Emergence
Post by: bluehillside Retd. on February 21, 2023, 04:39:11 PM
Vlad,

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Why do I think fundamental particles follow the laws of physics without reference to tax arrangements in Leichtenstein?
Er, because of the laws of physics.

Tax arrangements are an emergent from particles which don't have tax arrangements.

You don’t get it still. In an entirely deterministic model, if you know precisely all the starting conditions and you have unlimited computing power then there’s no inherent reason in principle that you couldn’t predict the future tax arrangements of Liechtenstein.

What “laws of physics” do you think make that not the case?
   
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 21, 2023, 05:20:15 PM
Vlad,

You don’t get it still. In an entirely deterministic model, if you know precisely all the starting conditions and you have unlimited computing power then there’s no inherent reason in principle that you couldn’t predict the future tax arrangements of Liechtenstein.

What “laws of physics” do you think make that not the case?
   
So what is it about particles that necessitates tax arrangements. What property of the quark makes them inevitable?
Title: Re: Reductionism vs. Emergence
Post by: bluehillside Retd. on February 21, 2023, 05:26:36 PM
Vlad,

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So what is it about particles that necessitates tax arrangements. What property of the quark makes them inevitable?

Doesn't matter. What is it about oxygen atoms and hydrogen atoms that "necessitates" wetness? Either you accept that the universe is deterministic in character as the evidence suggests, or you don't. If you do then in principle at least the tax arrangements of Liechtenstein were predictable all the way from the big bang; if you don't though then you have a big job to explain your abandonment of the model.

Oh, and "So what is it about particles that necessitates tax arrangements. What property of the quark makes them inevitable?" is just an expression of your incredulity by the way, not an argument.   
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 22, 2023, 12:03:39 AM
Vlad,

Doesn't matter. What is it about oxygen atoms and hydrogen atoms that "necessitates" wetness? Either you accept that the universe is deterministic in character as the evidence suggests, or you don't. If you do then in principle at least the tax arrangements of Liechtenstein were predictable all the way from the big bang; if you don't though then you have a big job to explain your abandonment of the model.

Oh, and "So what is it about particles that necessitates tax arrangements. What property of the quark makes them inevitable?" is just an expression of your incredulity by the way, not an argument.   
This post is non sequitur to any recent discussion.
No amount of studying particles will reveal anything about tax arrangements but might give you a fair bit of detail about where those particles are.
An infinitely large computer will tell you everything? Will it really? don't you have to programme it first.
Which brings us to the question of information and the amount of substrate to carry it.
There are too many ifs in your argument and I don't think people are saying what you are alleging anyway.
Title: Re: Reductionism vs. Emergence
Post by: bluehillside Retd. on February 22, 2023, 10:34:15 AM
Vlad,

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This post is non sequitur to any recent discussion.

No it isn’t (presumably because you’ve never understood that term).

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No amount of studying particles will reveal anything about tax arrangements but might give you a fair bit of detail about where those particles are.

Just repeating the assertion doesn’t justify it. How do you know that, given perfect understanding of the opening conditions and unlimited computing power, it wouldn’t be possible in principle to work out from the big bang onwards what the current tax arrangements of Liechtenstein would be?

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An infinitely large computer will tell you everything? Will it really? don't you have to programme it first.

Whoosh!

First, no-one said that it would tell you “everything” – just the outcomes of a deterministic model, no matter how complex.

Second, whether and who would programme the theoretical computer has no relevance to the point here - namely that in principle at least deterministic models are predictable no matter what the author of the article you linked to asserted.
 
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Which brings us to the question of information and the amount of substrate to carry it.

No it it doesn’t. It’s an in principle argument, not an in practice one (“You, your dog, and the specifics of your person-dog affection could not be predicted, even in principle, even from perfect knowledge of all your elementary particles”).

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There are too many ifs in your argument and I don't think people are saying what you are alleging anyway.

There are no “ifs” - it’s just a simple point in principle, and “people” (ie, the author) are saying exactly that - see quote above. 
Title: Re: Reductionism vs. Emergence
Post by: Stranger on February 22, 2023, 11:34:01 AM
This discussion seems to be confusing reduction with prediction.

It's difficult to say whether perfect prediction is possible, even in principle, because of two reasons.

Firstly, we don't know if the universe is deterministic or not. The problem here is quantum mechanics (well, quantum field theory really). Whether we live in a deterministic universe depends on the interpretation of quantum mechanics; and even if you choose the most popular deterministic version, 'Many Worlds', it doesn't actually mean that what we will observe will be deterministic. The macro world appears to be deterministic but it isn't difficult (as in Schrödinger's cat) to magnify single quantum events to the macro scale (I know the cat was a thought experiment but we are perfectly capable of doing something like that in practice - preferably without killing any cats).

Secondly, chaos also throws a bit of a spanner in the works, if the universe contains genuine continua (e.g. space-time). If it does, then perfect knowledge of the position of just one particle would require an infinite amount of data (it's not even just countable infinity, the infinity of a continuum is 'bigger'). Chaos means that you would need perfect knowledge because it can potentially magnify the tiniest of differences in the starting conditions, given enough time. I guess you could argue that an in principle argument could involve a truly infinite amount of starting data but you would need a literally infinite computer, not just one with unlimited storage and processing power, i.e. 'as big and powerful as necessary'.

All of that is different from reduction. As I explained in #21 (http://www.religionethics.co.uk/index.php?topic=19509.msg857363#msg857363), you can deduce chemical properties of atoms from the basic quantum mechanics of the individual particles. Reduction would mean that, in principle, you can carry on up, explaining biology in terms of chemistry, then on up though behaviour and all the way up to tax arrangements. I don't see any problems with that in principle, and if you claim we can't, then it does call into question the laws of physics.
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 22, 2023, 12:08:14 PM
This discussion seems to be confusing reduction with prediction.

It's difficult to say whether perfect prediction is possible, even in principle, because of two reasons.

Firstly, we don't know if the universe is deterministic or not. The problem here is quantum mechanics (well, quantum field theory really). Whether we live in a deterministic universe depends on the interpretation of quantum mechanics; and even if you choose the most popular deterministic version, 'Many Worlds', it doesn't actually mean that what we will observe will be deterministic. The macro world appears to be deterministic but it isn't difficult (as in Schrödinger's cat) to magnify single quantum events to the macro scale (I know the cat was a thought experiment but we are perfectly capable of doing something like that in practice - preferably without killing any cats).

Secondly, chaos also throws a bit of a spanner in the works, if the universe contains genuine continua (e.g. space-time). If it does, then perfect knowledge of the position of just one particle would require an infinite amount of data (it's not even just countable infinity, the infinity of a continuum is 'bigger'). Chaos means that you would need perfect knowledge because it can potentially magnify the tiniest of differences in the starting conditions, given enough time. I guess you could argue that an in principle argument could involve a truly infinite amount of starting data but you would need a literally infinite computer, not just one with unlimited storage and processing power, i.e. 'as big and powerful as necessary'.

All of that is different from reduction. As I explained in #21 (http://www.religionethics.co.uk/index.php?topic=19509.msg857363#msg857363), you can deduce chemical properties of atoms from the basic quantum mechanics of the individual particles. Reduction would mean that, in principle, you can carry on up, explaining biology in terms of chemistry, then on up though behaviour and all the way up to tax arrangements. I don't see any problems with that in principle, and if you claim we can't, then it does call into question the laws of physics.
Very fair assessment, though in terms of moving from chemistry to biology though there are linguistic differences between the two as i was informed by a chemist friend hugely irritated by what he saw as sloppy and innaccurate use of chemical terms and meanings by biologists.
Title: Re: Reductionism vs. Emergence
Post by: Stranger on February 22, 2023, 12:19:20 PM
Very fair assessment, though in terms of moving from chemistry to biology though there are linguistic differences between the two as i was informed by a chemist friend hugely irritated by what he saw as sloppy and innaccurate use of chemical terms and meanings by biologists.

There are linguistic differences at every level, including, of course, physics and chemistry, and probably even more between physics (quantum mechanics) and semiconductor design (that requires quantum mechanics).
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 22, 2023, 12:26:16 PM
There are linguistic differences at every level, including, of course, physics and chemistry, and probably even more between physics (quantum mechanics) and semiconductor design (that requires quantum mechanics).
True. I wonder though, how far that reflects the emergence of novel phenomena.
Title: Re: Reductionism vs. Emergence
Post by: jeremyp on February 22, 2023, 12:33:34 PM
They can be working fine within the laws of Physics without describing the tax arrangements of the principality of Leichtenstein in any meaningful way.

But they do. It's just that humans lack the intellect and resources to understand the tax laws of Liechtenstein in terms of the fundamental laws of physics.
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 22, 2023, 12:50:36 PM
But they do. It's just that humans lack the intellect and resources to understand the tax laws of Liechtenstein in terms of the fundamental laws of physics.
Sounds like understanding beethoven's Fifth in terms of Yoghurts.
Title: Re: Reductionism vs. Emergence
Post by: jeremyp on February 22, 2023, 12:53:25 PM
Sounds like understanding beethoven's Fifth in terms of Yoghurts.

You're the only person I have ever met who claims that Beethoven's Fifth Symphony is composed of yoghurt.
Title: Re: Reductionism vs. Emergence
Post by: Sebastian Toe on February 22, 2023, 12:57:15 PM
You're the only person I have ever met who claims that Beethoven's Fifth Symphony is composed of yoghurt.
You have to be cultured to appreciate it?
 ;)
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 22, 2023, 12:58:42 PM
You're the only person I have ever met who claims that Beethoven's Fifth Symphony is composed of yoghurt.
What I am suggesting in a humourous fashion (I thought it was funny and at the end of the day that's what counts) Is perhaps we can't understand Tax arrangements in terms of fundamental particles and not just because we are human.
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 22, 2023, 12:59:20 PM
You have to be cultured to appreciate it?
 ;)
Have you been dabbling in the Yakult?
Title: Re: Reductionism vs. Emergence
Post by: bluehillside Retd. on February 22, 2023, 01:01:37 PM
Vlad,

Quote
What I am suggesting in a humourous fashion (I thought it was funny and at the end of the day that's what counts) Is perhaps we can't understand Tax arrangements in terms of fundamental particles and not just because we are human.

In principle at least, why not? 
Title: Re: Reductionism vs. Emergence
Post by: jeremyp on February 22, 2023, 01:04:11 PM
What I am suggesting in a humourous fashion (I thought it was funny and at the end of the day that's what counts) Is perhaps we can't understand Tax arrangements in terms of fundamental particles and not just because we are human.

It looked to me like you were suggesting that Beethoven' s music was made of yoghurt. Although I notice that you capitalised the Y. Was Yoghurt a hitherto unknown composer from whom Beethoven stole his harmonies?
Title: Re: Reductionism vs. Emergence
Post by: bluehillside Retd. on February 22, 2023, 01:11:31 PM
Stranger,

Quote
This discussion seems to be confusing reduction with prediction.

It's difficult to say whether perfect prediction is possible, even in principle, because of two reasons.

Firstly, we don't know if the universe is deterministic or not. The problem here is quantum mechanics (well, quantum field theory really). Whether we live in a deterministic universe depends on the interpretation of quantum mechanics; and even if you choose the most popular deterministic version, 'Many Worlds', it doesn't actually mean that what we will observe will be deterministic. The macro world appears to be deterministic but it isn't difficult (as in Schrödinger's cat) to magnify single quantum events to the macro scale (I know the cat was a thought experiment but we are perfectly capable of doing something like that in practice - preferably without killing any cats).

Secondly, chaos also throws a bit of a spanner in the works, if the universe contains genuine continua (e.g. space-time). If it does, then perfect knowledge of the position of just one particle would require an infinite amount of data (it's not even just countable infinity, the infinity of a continuum is 'bigger'). Chaos means that you would need perfect knowledge because it can potentially magnify the tiniest of differences in the starting conditions, given enough time. I guess you could argue that an in principle argument could involve a truly infinite amount of starting data but you would need a literally infinite computer, not just one with unlimited storage and processing power, i.e. 'as big and powerful as necessary'.

All of that is different from reduction. As I explained in #21, you can deduce chemical properties of atoms from the basic quantum mechanics of the individual particles. Reduction would mean that, in principle, you can carry on up, explaining biology in terms of chemistry, then on up though behaviour and all the way up to tax arrangements. I don't see any problems with that in principle, and if you claim we can't, then it does call into question the laws of physics.

Good post, but when the argument is expressed as an “if” thought experiment (“if the universe is deterministic, then….” etc) then I can’t see how the author of the article Vlad linked to justifies his comment on reductionism specifically that: “You, your dog, and the specifics of your person-dog affection could not be predicted, even in principle, even from perfect knowledge of all your elementary particles”.   
Title: Re: Reductionism vs. Emergence
Post by: bluehillside Retd. on February 22, 2023, 01:13:32 PM
Jeremy,

Quote
...from whom Beethoven stole his harmonies?

How dairy?  :D

(I'll get me jacket.)
Title: Re: Reductionism vs. Emergence
Post by: jeremyp on February 22, 2023, 01:25:31 PM
Stranger,

Good post, but when the argument is expressed as an “if” thought experiment (“if the universe is deterministic, then….” etc) then I can’t see how the author of the article Vlad linked to justifies his comment on reductionism specifically that: “You, your dog, and the specifics of your person-dog affection could not be predicted, even in principle, even from perfect knowledge of all your elementary particles”.   

Also, even in the Copenhagen interpretation of QM, which is non deterministic, you can certainly predict probabilities of future events in principle, if not exactly which events will happen.
Title: Re: Reductionism vs. Emergence
Post by: Stranger on February 22, 2023, 03:11:35 PM
Good post, but when the argument is expressed as an “if” thought experiment (“if the universe is deterministic, then….” etc) then I can’t see how the author of the article Vlad linked to justifies his comment on reductionism specifically that: “You, your dog, and the specifics of your person-dog affection could not be predicted, even in principle, even from perfect knowledge of all your elementary particles”.   

Okay, missed that as a starting assumption, which only leaves you with the potential chaos problem and whether you're prepared to accept a real infinity in an 'in principle' argument. My impression (I may be wrong) is that it would be somewhat unconventional in that the general definition of computability is whether, in principle, you can solve it with a Turning machine, or equivalently, an (unlimited) register machine - which are unbounded, in the sense that there is no consideration of any practical limitations (they can handle any number of instructions, any amount of data, and no consideration is given to how long it would take) but are constrained to be finite in any particular problem.

But again, this is all about prediction (of the future from some defined starting point), rather than reduction.
Title: Re: Reductionism vs. Emergence
Post by: Stranger on February 22, 2023, 03:21:24 PM
Also, even in the Copenhagen interpretation of QM, which is non deterministic, you can certainly predict probabilities of future events in principle, if not exactly which events will happen.

Yes, this is certainly true, but you quickly run into problems with prediction the more successive probabilistic events you are considering because the probability of any particular outcome will quickly become tiny, even if the probability of the individual events in the chain are quite high.
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 22, 2023, 03:37:30 PM
Also, even in the Copenhagen interpretation of QM, which is non deterministic, you can certainly predict probabilities of future events in principle, if not exactly which events will happen.
Predicting future events is what use to be known as clairvoyance or prophesy etc. I am not talking about anything like that. What I am talking about is an explanatory gap between the components that give rise to emergents and the emergents themselves, novel properties if you like. I see no reason why that could not arise within a deterministic context or a non deterministic context.

However here is your opportunity to back up your contention. Name a future event which results in a novel property and give us the probability of it. I'm not talking here about say, the probabilty of a number of water molecules becoming something wet but a new property or as you say a future event that hasn't been seen.
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 22, 2023, 03:56:27 PM
You, your dog, and the specifics of your person-dog affection could not be predicted, even in principle, even from perfect knowledge of all your elementary particles”.   
This first appeared in reply 3. Your post.
Title: Re: Reductionism vs. Emergence
Post by: bluehillside Retd. on February 22, 2023, 04:08:50 PM
Vlad,

Quote
Predicting future events is what use to be known as clairvoyance or prophesy etc. I am not talking about anything like that.

Nor is anyone else.

Quote
What I am talking about is an explanatory gap between the components that give rise to emergents and the emergents themselves, novel properties if you like. I see no reason why that could not arise within a deterministic context or a non deterministic context.

“Explanatory gap” in practice or in principle? The article refers specifically to “in principle”.

Quote
However here is your opportunity to back up your contention. Name a future event which results in a novel property and give us the probability of it. I'm not talking here about say, the probabilty of a number of water molecules becoming something wet but a new property or as you say a future event that hasn't been seen.

You’re missing the point still. A deterministic model in which you have perfect knowledge of the starting conditions and unlimited computing power (leaving aside for now Stranger’s reservations about the possibility of “unlimited”) is predictable regardless of the complexity involved, at least in principle. If you think otherwise, then it’s your job to explain why not.   
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 22, 2023, 04:38:24 PM
Vlad,

Nor is anyone else.

“Explanatory gap” in practice or in principle? The article refers specifically to “in principle”.

You’re missing the point still. A deterministic model in which you have perfect knowledge of the starting conditions and unlimited computing power (leaving aside for now Stranger’s reservations about the possibility of “unlimited”) is predictable regardless of the complexity involved, at least in principle. If you think otherwise, then it’s your job to explain why not.   
The explanation is plain in the definitions of emergent properties namely novel and not possessed by the components so the question is how can these be predicted from entities that do not possess them? Over to you. Saying ''We can't now because we are only human but we can in principle'' seems like meaningless mealy mouth nonsense.
Title: Re: Reductionism vs. Emergence
Post by: bluehillside Retd. on February 22, 2023, 04:45:32 PM
Vlad,

Quote
The explanation is plain in the definitions of emergent properties namely novel and not possessed by the components so the question is how can these be predicted from entities that do not possess them? Over to you. Saying ''We can't now because we are only human but we can in principle'' seems like meaningless mealy mouth nonsense.

The components not having the properties of the phenomenon that emerges from them has nothing to do with whether or not the latter can be predicted from the former (given perfect knowledge of the starting conditions and sufficient computing power etc).

I thought you claimed to know something about emergence? 
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 22, 2023, 05:55:17 PM
Vlad,

The components not having the properties of the phenomenon that emerges from them has nothing to do with whether or not the latter can be predicted from the former (given perfect knowledge of the starting conditions and sufficient computing power etc).

I thought you claimed to know something about emergence?
You are just adding to a list of unjustified assertions concerning your point of view.
Let us review some.
All novel events and properties can be predicted from entities that do not possess them.
We cannot do so.
We could in principle.

These need to be justified.
 
Title: Re: Reductionism vs. Emergence
Post by: bluehillside Retd. on February 22, 2023, 06:06:39 PM
Vlad,

Quote
You are just adding to a list of unjustified assertions concerning your point of view.
Let us review some.
All novel events and properties can be predicted from entities that do not possess them.
We cannot do so.
We could in principle.

These need to be justified.

See Replies 10 & 12 for the explanation of “default”. Once again, the claims is: “You, your dog, and the specifics of your person-dog affection could not be predicted, even in principle, even from perfect knowledge of all your elementary particles”.

The default response based on anything we verifiably know so far is that that’s wrong. If you think that default response should be amended or abandoned though, then it’s your job to explain why.   

Try to remember this.
Title: Re: Reductionism vs. Emergence
Post by: jeremyp on February 22, 2023, 06:23:31 PM
Yes, this is certainly true, but you quickly run into problems with prediction the more successive probabilistic events you are considering because the probability of any particular outcome will quickly become tiny, even if the probability of the individual events in the chain are quite high.
But the point is not whether it is practical for humans to do it, but whether it can be done in principle.

Vlad's article seems to claim that it is impossible even in principle.
Title: Re: Reductionism vs. Emergence
Post by: Stranger on February 22, 2023, 06:56:07 PM
But the point is not whether it is practical for humans to do it, but whether it can be done in principle.

Vlad's article seems to claim that it is impossible even in principle.

Sorry but I don't see the relevance. The point I made has nothing to do with whether humans can do the calculations or not. If you're trying to make a prediction that involves long chains of probabilistic events, then the longer the chain, the more possible outcomes you have and the lower the probability of even the most probable one becomes. If every outcome has a tiny probability, then it isn't really much of a prediction.

But as I said before, there seems to be a confusion between predicating the future (from a point in time, somebody mentioned from the big bang) and emergence, i.e. predicting properties that will emerge from the combination of entities that don't have them individually. In the latter case, the probabilities might not matter at all - as in the example I gave of making a quantum model of an atom and predicting its chemical properties (which none of the parts have themselves).
Title: Re: Reductionism vs. Emergence
Post by: Free Willy on February 23, 2023, 09:14:22 AM
Vlad,

See Replies 10 & 12 for the explanation of “default”. Once again, the claims is: “You, your dog, and the specifics of your person-dog affection could not be predicted, even in principle, even from perfect knowledge of all your elementary particles”.

The default response based on anything we verifiably know so far is that that’s wrong. If you think that default response should be amended or abandoned though, then it’s your job to explain why.   

Try to remember this.
Not sure of a claim here but a speculation based on the inability to demonstrate an asserted principle as exemplified by your own continual refusal or inability. Nature abhors a vacuum and I abhor yours.
Title: Re: Reductionism vs. Emergence
Post by: bluehillside Retd. on February 23, 2023, 11:27:32 AM
Vlad,

Quote
Not sure of a claim here…

Given that I’ve copied and pasted it so often, why aren't you sure of that? Here it is a gain though so you have no excuse not to know what it is:

“You, your dog, and the specifics of your person-dog affection could not be predicted, even in principle, even from perfect knowledge of all your elementary particles.”

Clear now?

Quote
…but a speculation based on the inability to demonstrate an asserted principle as exemplified by your own continual refusal or inability. Nature abhors a vacuum and I abhor yours.

And for those of us working in English?

I’ll try to put it more simply for you then: every time I throw something out of my window it hits the deck shortly afterwards. My default position therefore is that every time you throw something out of the window the same outcome will follow. That’s not to claim a universal truth that things thrown out of windows will always hit the deck shortly afterwards, nor even is it the claim that one day an object I throw out of the window won’t shoot upwards instead. The clue is in the word “default”.

Do you understand this now?   
Title: Re: Reductionism vs. Emergence
Post by: bluehillside Retd. on February 23, 2023, 02:38:21 PM
Stranger

Quote
Sorry but I don't see the relevance. The point I made has nothing to do with whether humans can do the calculations or not. If you're trying to make a prediction that involves long chains of probabilistic events, then the longer the chain, the more possible outcomes you have and the lower the probability of even the most probable one becomes. If every outcome has a tiny probability, then it isn't really much of a prediction.

But as I said before, there seems to be a confusion between predicating the future (from a point in time, somebody mentioned from the big bang) and emergence, i.e. predicting properties that will emerge from the combination of entities that don't have them individually. In the latter case, the probabilities might not matter at all - as in the example I gave of making a quantum model of an atom and predicting its chemical properties (which none of the parts have themselves).

Much as I hesitate to wade into an area in which you clearly know more than I do, for an in principle argument does the number of probabilistic events matter? Isn’t this a bit like the black hole paradox whereby it’s now generally thought (as I understand it) that information is not destroyed in a black sole so, given enough computing power, it should be possible to throw, say, Vlad into a black hole and then predictably reconstruct him after after evaporation?     

As for emergence, what then would be inherently problematic with predicting the characteristics of an emergent phenomenon (or of other emergent phenomena many generations later) given perfect, universal knowledge of the starting conditions and (effectively) unlimited computing power? 
Title: Re: Reductionism vs. Emergence
Post by: Stranger on February 23, 2023, 04:57:59 PM
Much as I hesitate to wade into an area in which you clearly know more than I do...

Wade ahead.  :)

...for an in principle argument does the number of probabilistic events matter?

It depends on what you want to achieve. There is a difference that I've been trying to point out between predicting the future from some point in time and dealing with emergence.

An in principle argument can't change the underlying mathematics, so if you're trying to predict an inherently probabilistic chain of events, then the number of possible outcomes grows very rapidly, so for a series of events for which there are only two outcomes, there are 2N outcomes for N events. At the same time, the probability of any one particular outcome is the product of the probabilities in the chain that leads to it, and so the probability of even the most probable outcome will rapidly shrink, even if the individual events in the chain are highly probable individually. So, to the extent probabilistic events matter to the prediction you're trying to make, the number of outcomes will quickly become vast and the probabilities tiny for each one. A perfect calculation, with infinite computing power, isn't going to give you much of a prediction.

The problem with prediction is therefore that we simply don't know if the universe is deterministic or relies on probabilities. You have no problem with perfect predictions for a deterministic universe (except the possible problem with chaos and continua that I mentioned before), but if it relies on fundamental probabilities, then you do.

On the other hand, if you're dealing with emergence, i.e. properties that emerge from the interactions of parts that do not possess them individually, it might not matter. To go back to the example of a quantum model of an atom, you're not really interested in what one specific atom does, you're interested in the generic properties that different kinds of atoms (elements) have. The emergent properties of atoms are mostly to do with the states it is possible for its elections to be in and, specifically, the energies associated with each one. So, for example, the spectral lines associated with each element correspond to the energy differences between possible states of the electrons, because they represent absorption or emission of photons with those energies, and energy is directly related to frequency. The model cannot tell you about what state one atom is in, or where one electron is, but it does tell you that the possible energies are quantised and what the allowed energies are - and that's all you really need to know. [I'm glossing over a lot of detail here, but I'm trying to get the basic idea across as simply as I can.]

Isn’t this a bit like the black hole paradox whereby it’s now generally thought (as I understand it) that information is not destroyed in a black sole so, given enough computing power, it should be possible to throw, say, Vlad into a black hole and then predictably reconstruct him after after evaporation?

Talk about opening the proverbial can of worms! I think I'll pass on this for the moment because it risks either going off at a tangent, or possibly just revisiting the same unknowns from a different point of view. We can go back to it if necessary.

I hope what I've said covers the rest of your questions, if not, let me know and I'll try again.
Title: Re: Reductionism vs. Emergence
Post by: bluehillside Retd. on February 26, 2023, 03:11:00 PM
Stranger,

Quote
Wade ahead.

Thank you!

Quote
It depends on what you want to achieve. There is a difference that I've been trying to point out between predicting the future from some point in time and dealing with emergence.

But my question is why. Leaving aside for now the complexity of the calculation, what special characteristic do emergent phenomena have that, just by virtue of being emergent, makes them non-predictable even in principle – in essence the claim of the author Vlad linked to in the OP, and rebutted by the author (Ethan Siegel) I linked to in Reply 1?

In other words, why in principle should it be any more difficult/impossible for the reductionist model to predict an emergent future event than it is to predict a non-emergent one?

Quote
An in principle argument can't change the underlying mathematics, so if you're trying to predict an inherently probabilistic chain of events, then the number of possible outcomes grows very rapidly, so for a series of events for which there are only two outcomes, there are 2N outcomes for N events. At the same time, the probability of any one particular outcome is the product of the probabilities in the chain that leads to it, and so the probability of even the most probable outcome will rapidly shrink, even if the individual events in the chain are highly probable individually. So, to the extent probabilistic events matter to the prediction you're trying to make, the number of outcomes will quickly become vast and the probabilities tiny for each one. A perfect calculation, with infinite computing power, isn't going to give you much of a prediction.

Yes I get that iterative probability events spiral quickly (exponentially?) into very, very hard to predict outcomes but isn’t this still a computing problem of scale rather than one of principle? Take a horse race for example - sure I could study the form, talk to the trainers etc before placing my bet but there are still vast numbers of unknown variables potentially in play that could affect the result. What though if instead I knew absolutely everything there was to know - every possible component of the horses, every possible thought process they would have, every possible weather parameter, every possible chance of a bird passing by and distracting the horse I fancied, every everything in other words? That is, what if there were be no more unknowns that could affect the outcome? And let’s say too that I knew all that ab initio, and also that I had a big enough computer to do the calculations - would I then know in advance the winner with no possibility of not cashing in? Isn’t that what a deterministic model would imply?           

Quote
The problem with prediction is therefore that we simply don't know if the universe is deterministic or relies on probabilities. You have no problem with perfect predictions for a deterministic universe (except the possible problem with chaos and continua that I mentioned before), but if it relies on fundamental probabilities, then you do.

Siegel covers this I think:

Some composite structures and some properties of complex structures will be easily explicable from the underlying rules, sure, but the more complex your system becomes, the more difficult you can expect it will be to explain all of the various phenomena and properties that emerge.
That latter piece cannot be considered “evidence against reductionism” in any way, shape, or form. The fact that “There exists this phenomenon that lies beyond my ability to make robust predictions about” is never to be construed as evidence in favor of “This phenomenon requires additional laws, rules, substances, or interactions beyond what’s presently known.

You either understand your system well-enough to understand what should and shouldn’t emerge from it, in which case you can put reductionism to the test, or you don’t, in which case, you have to go back down to the null hypothesis: that there’s no evidence for anything novel.

And, to be clear, the “null hypothesis” is that the Universe is 100% reductionist. That means a suite of things.

• That all structures that are built out of atoms and their constituents — including molecules, ions, and enzymes — can be described based on the fundamental laws of nature and the component structures that they’re made out of.

• That all larger structures and processes that occur between those structures, including all chemical reactions, don’t require anything more than those fundamental laws and constituents.

• That all biological processes, from biochemistry to molecular biology and beyond, as complex as they might appear to be, are truly just the sum of their parts, even if each “part” of a biological system is remarkably complex.

• And that everything that we regard as “higher functioning,” including the workings of our various cells, organs, and even our brains, doesn’t require anything beyond the known physical constituents and laws of nature to explain.

To date, although it shouldn’t be controversial to make such a statement, there is no evidence for the existence of any phenomena that falls outside of what reductionism is capable of explaining.


This seems persuasive to me. Does it to you?

Quote
On the other hand, if you're dealing with emergence, i.e. properties that emerge from the interactions of parts that do not possess them individually, it might not matter. To go back to the example of a quantum model of an atom, you're not really interested in what one specific atom does, you're interested in the generic properties that different kinds of atoms (elements) have. The emergent properties of atoms are mostly to do with the states it is possible for its elections to be in and, specifically, the energies associated with each one. So, for example, the spectral lines associated with each element correspond to the energy differences between possible states of the electrons, because they represent absorption or emission of photons with those energies, and energy is directly related to frequency. The model cannot tell you about what state one atom is in, or where one electron is, but it does tell you that the possible energies are quantised and what the allowed energies are - and that's all you really need to know. [I'm glossing over a lot of detail here, but I'm trying to get the basic idea across as simply as I can.]

OK (I think) but I’m still not seeing a qualitative difference between the predictability of non-emergent outcomes and emergent ones. Perhaps this is what you meant by “On the other hand, if you're dealing with emergence, i.e. properties that emerge from the interactions of parts that do not possess them individually, it might not matter”? Does not the explanation you set out here apply to both categories?     

Quote
Talk about opening the proverbial can of worms! I think I'll pass on this for the moment because it risks either going off at a tangent, or possibly just revisiting the same unknowns from a different point of view. We can go back to it if necessary.

Yeah I know - seems I’ve been listening to the Infinite Monkey Cage podcast a little too much lately (!) but the point was just a simple one - ie, that no matter how vast (and currently unachievable) the computing power necessary, that’s no reason to invalidate the hypothesis.   

Quote
I hope what I've said covers the rest of your questions, if not, let me know and I'll try again.

Yes, thank you - though I’m still left with the same open question about why, fundamentally, for prediction purposes emergent phenomena break the reductionist model of reality (as Vlad’s author claims) when it seems to me they do no such thing (as my man says).     

Title: Re: Reductionism vs. Emergence
Post by: Stranger on February 26, 2023, 04:34:31 PM
But my question is why. Leaving aside for now the complexity of the calculation, what special characteristic do emergent phenomena have that, just by virtue of being emergent, makes them non-predictable even in principle – in essence the claim of the author Vlad linked to in the OP, and rebutted by the author (Ethan Siegel) I linked to in Reply 1?

In other words, why in principle should it be any more difficult/impossible for the reductionist model to predict an emergent future event than it is to predict a non-emergent one?

It isn't. The problem with predicting the future, from some staring point in time, depends entirely on if the universe is deterministic or not; it has nothing at all to do with emergence. That's why I was trying to draw a distinction between that and 'predicting' or explaining from first principles (as you can usually see what has actually emerged) emergent properties.

The former is to do with the passage of time and how things develop over time, while the latter is to do with going 'up' the hierarchy of emergent phenomena, and has nothing to do with development over time per se.

Yes I get that iterative probability events spiral quickly (exponentially?) into very, very hard to predict outcomes but isn’t this still a computing problem of scale rather than one of principle? Take a horse race for example - sure I could study the form, talk to the trainers etc before placing my bet but there are still vast numbers of unknown variables potentially in play that could affect the result. What though if instead I knew absolutely everything there was to know - every possible component of the horses, every possible thought process they would have, every possible weather parameter, every possible chance of a bird passing by and distracting the horse I fancied, every everything in other words? That is, what if there were be no more unknowns that could affect the outcome? And let’s say too that I knew all that ab initio, and also that I had a big enough computer to do the calculations - would I then know in advance the winner with no possibility of not cashing in? Isn’t that what a deterministic model would imply?           

Yes, it is (ignoring the chaos and continua problem for the moment). The problem is that we don't know for sure if it is fully deterministic or not.

Siegel covers this I think:

Some composite structures and some properties of complex structures will be easily explicable from the underlying rules, sure, but the more complex your system becomes, the more difficult you can expect it will be to explain all of the various phenomena and properties that emerge.
That latter piece cannot be considered “evidence against reductionism” in any way, shape, or form. The fact that “There exists this phenomenon that lies beyond my ability to make robust predictions about” is never to be construed as evidence in favor of “This phenomenon requires additional laws, rules, substances, or interactions beyond what’s presently known.

You either understand your system well-enough to understand what should and shouldn’t emerge from it, in which case you can put reductionism to the test, or you don’t, in which case, you have to go back down to the null hypothesis: that there’s no evidence for anything novel.

And, to be clear, the “null hypothesis” is that the Universe is 100% reductionist. That means a suite of things.

• That all structures that are built out of atoms and their constituents — including molecules, ions, and enzymes — can be described based on the fundamental laws of nature and the component structures that they’re made out of.

• That all larger structures and processes that occur between those structures, including all chemical reactions, don’t require anything more than those fundamental laws and constituents.

• That all biological processes, from biochemistry to molecular biology and beyond, as complex as they might appear to be, are truly just the sum of their parts, even if each “part” of a biological system is remarkably complex.

• And that everything that we regard as “higher functioning,” including the workings of our various cells, organs, and even our brains, doesn’t require anything beyond the known physical constituents and laws of nature to explain.

To date, although it shouldn’t be controversial to make such a statement, there is no evidence for the existence of any phenomena that falls outside of what reductionism is capable of explaining.


This seems persuasive to me. Does it to you?

I don't disagree with any of that but it's not about predicting the future from a given point in time, it's about explaining the higher levels, with all their emergent features, in terms of the lower, more fundamental levels.

OK (I think) but I’m still not seeing a qualitative difference between the predictability of non-emergent outcomes and emergent ones.

Probably because there isn't one. I obviously haven't managed to get the distinction I'm trying to make across. It's almost as if the two things, emergence and predicting the future, are orthogonal: one proceeds along the time axis and the other goes up the hierarchy of more complex emergent behaviour.

For example, if some hypothetical theorist, with access to unlimited computing power, had existed before there were any atoms, they may have been able to predict that some combinations of protons, neutrons, and electrons might come together to make atoms, that atoms may then be able to make molecules, and that some of them would be large and complex, how these could form the basis for organic chemistry, and then go on to predict life itself, yet have been totally unable (unless the universe is fully deterministic) to predict any of the specific details about the future in terms of events (the formation of a planet called Earth and the path of evolution that led to humans).

Yeah I know - seems I’ve been listening to the Infinite Monkey Cage podcast a little too much lately (!) but the point was just a simple one - ie, that no matter how vast (and currently unachievable) the computing power necessary, that’s no reason to invalidate the hypothesis.   

The black hole information problem is still not settled (although some physicists seem to have made up their minds, there are others that still disagree), because it arises from making certain assumptions one way or the other.

In a Newtonian universe, a prefect picture of the present would give you, not only a perfect prediction of the future, but also a perfect reconstruction of the past, because everything is deterministic and time-reversible, hence you could say that no information is lost or gained. The advent of general relativity and black holes seemed to kill the idea because the world-lines of some particles would become inaccessible when they passed the event horizon and would actually terminate at the singularity.

Then we have the further problem of quantum mechanics. Ignoring field theory for the sake of simplicity, the Schrödinger equation seems to offer just as much certainty as the Newtonian model. As long as the wave-function behaves according to it, it is also deterministic and time-reversible. The problem is that when you're doing a practical calculation and you do a measurement of some observable (position, spin, energy, etc.), then you then know the value of that for certain, and you basically throw the Schrödinger equation in the bin for a moment and start again with a wave-function that reflects your new-found certainty. This is what's called 'the collapse of the wave-function' or 'state reduction'. Some new information seems to have appeared (the value of the observable) and some lost (the exact history). Hence The Measurement Problem (https://en.wikipedia.org/wiki/Measurement_problem), which remains unresolved.

Add to that that we still don't know how to properly model black holes because we don't have a fully worked out and tested theory that unites quantum field theory with general relativity, and you're left with a lot of unknowns (perhaps more than some like to admit to and more than pop-science programs and articles might lead you to believe).

Again, I hope this helps but I don't mind carrying on this discussion, it makes a change from the endless repetition we get from some on here.   :)