Niels Bohr’s Argument for the Irreducibility of Biology to Physics (1994)
link.springer.com
link.springer.com
But what if the irreducible cell is made up of normal matter, but it has strongly emergent properties that can't be explained simply in terms of structure and function of it's physical properties? That's what would make it irreducible, if such things do exist.
I suppose there's a scale at which the "gap" becomes too large to call it "physics," but the larger the scale, the stranger it would be to find something irreducible across so many levels.
I don't want to argue about this or any word, but I think what was meant - and what I too would say - is that some things are emergent properties of interacting things. Yes, they consist of "physics stuff" following "physics rules", but also, together they create something new, on a higher level. If you take it apart it's gone, of course, and you go back to the physics. To give an example, something deliberately slightly extreme or ridiculous (depending on your POV): Try to examine the game of chess by looking at the atoms involved in a physical game.
Or, when I zoom in too far the forest disappears and I end up with first trees, then branches, then cells, then "physics". But someone who gets a degree in forest management does not benefit from learning particle physics, aside from the intellectual exercise of course. Some things stop existing if you zoom in too far, there is no "forest" or "love" or "chess" any more all the way "down there".
I think there is a misunderstanding, people talking past one another. Some people (here, but in general) think what is meant is something "meta-physical", esoteric. At least for me that's not true at all. There isn't anything magic, there is physics. But it took me decades to get to the POV that I tried to present here, which is just a different angle - and "POV" (literally, just shifting position, still looking at the same physical scientifically explorable universe). I think this is like what I remember from many higher math education revelations - you fail to see what the teacher is trying to say, and when you finally see it it' sooooo simple, just a different point of view, not actually different from what you know. What I'm trying to say is, if you don't understand what someone might mean like in this case, talking about "emergent properties" and the like, please don't assume they leave known science behind to go on an esoteric trip. It's got something to do with us not being "god", seeing the entire universe at once, but only being able to shine an extremely tiny extremely focused beam at one extremely tiny detail. So even if we had a few formulas for _everything_ (all energy, all matter, incl. what now is the dark stuff), it would not help us when we try to shine our tiny light at a higher level, so we need a different model even though the components everything is made of are more "fundamental". When you have surgery, you don't want a particle physicist wielding the knife, and you probably don't care if the surgeon would fail every elementary quantum physics question. It is just not useful if you want to do something on a much higher level.
It may not be so to a "god", but to our small minds all those basic tiny "physics things" working together create something new on top of them, and it gets lost if you start looking at the parts. Of course those components, atoms and below, are still explainable using nothing but physics. Just not a huge amount all of them together, interacting in ways for which we have created models far above physics, unless you look at mass/force/etc. Each time you zoom in you see the physics (or if you drop tree and measure the force of its impact, but even the part of physics you use there is far above the low level stuff).
Last example: Imagine all models gone, in all fields. Only the most low level physics exists. Try to explain the chess rules :)
Anyway, that's just my interpretation.
Whether emergence can explain everything is another matter though, and I think that's where "irreducibility" might come into play.
So why do we have these threads right here, that prompted me to write this?
> Whether emergence can explain everything
Nothing can explain "everything". What does that even mean? I refer back to my comment. You use the right tool for the job, and that is a different one depending on context and "zoom level". See my comment? As I already wrote, even if you had a "perfect" low(est) level model, of what use is it to you on a much higher level? You cannot deal with an unmanageable amount of "low level" model (the "but in theory" argument is not even a good one in theory - reminds me of "but I can in theory imagine things happening at the exact same time light years away" before relativity became way too established for anyone to dare make that kind of statement to not be laughed at). You can't use the same model for everything. Even if you had the perfect knowledge of the lowest level you'd have "emergent models" on higher levels. You can't work with quantum theory to explain chess (which, in addition, is disconnected from the actual physical chess pieces used, it could even just be electrons in a computer instead of wooden or metal or plastic chess pieces).
PS:
Using the opportunity of the follow up comment to add to my original one:
Another POV is - just another mental model, not "the ultimate explanation for everything", one model among many - is that the low(est) level just is the hardware, the silicon. When you write software you don't care about the (exchangeable, extremely variable) hardware underneath. Without it there would not be "chess" - there would be many "chesses" because the game in software would be something completely different from the game using wooden pieces. We would not see any of those high level concepts because we would drown in detail.
I'm not saying I argue for the opposite, but that is very definitive statement in need of a very strong argument to be taken seriously.
> What does that even mean?
Things that we don't even know how to talk about yet, like consciousness.
Even if consciousness is just an emergent phenomenon, this still doesn't explain the subjective experience of consciousness. Subjective experience might be irreducible, but it might not. We don't know yet.
From what I understand, you're claiming that we can't explain higher levels of emergence in terms of lower levels. But that's not true, and your example of hardware/software is the prime example of that. We can explain or model every level of abstraction perfectly in terms of the preceding, lower level of abstraction, until we get to the quantum mechanical properties of the substrate your software is running on.
Whether it's practical to talk about the rules of chess in terms of QM is another matter - it's not - but I'd maybe argue that's because we're not intelligent enough to hold enough information at once in our brains, not because of some inherent impossibility of doing so.
Profound.
The claim is that mental events are supernatural?
In which case it sounds like there should be some mental events or experiences that are impervious to physical interference. So for example there is no conceivable physical intervention that could affect them. Do you believe there may be mental phenomena that are not causally related to physical processes in that way? It sounds like this should be testable.
I think he is only saying that an empirical language alone will not be enough to relate mental processes to physical ones. You have to define what a mental event really is before you can properly test anything about it, and depending on what definition you choose it might be inherently un-testable. If you define a mental process as being composed of physical processes from the start then of course you will conclude that all mental processes are influenced by physical ones. There are other possible definitions though such as physical processes being composed of multiple mental processes (the opposite of the last) in which case no physical test could be performed to verify a "change" occurred in the mental subject (but a "mental test" of sorts might still be able to tell us)
It's like saying you can't model a football game in terms of the behavior of proteins. Sure there are proteins, and there is no magic anywhere, but the conceptual gap is just too vast.
It's also not just about adding more variables because "it's complicated". Biology for example seems to be highly reflexive, that sort of behaviour can't really be accounted for in basic causal models. At best we have models which resemble fluid dynamics, and fluid dynamics is only as good as it is because we don't reduce the phenomena down to every molecule.
A for loop in a computer program is a property. It causes a behaviour. It can only do that because it is encoded in the materials of the computer. The question is, are there any properties a biological system can have that are not encoded in its physical constituents? Anyone answering ‘yes’ to that question really needs to provide a very clear answer as to how they think that might be possible and how else that property might arise.
I believe the answer is that there are properties which only come into existence once you have the right physical arrangement, but these properties can't be predicted in advance from the physical constituents.
As to how it could be possible that truly novel properties come into existence, that's not really different than how it can be possible that QM can have indeterminate properties, or anything that's physically fundament for which we have no explanation. Something happens to exist, and we don't know whether there is answer to why anything exists.
There's also other possibilities, like the existence of abstract and universal entities, such as numbers or universals. How is it that every electron has the exact same charge and mass? Is electron a universal? Why does math work so well for physics? Are there laws of nature that govern the world (make it be a certain way as opposed to just being regularities)? That sort of thing.
In order for such properties to not be predictable from the physical constituents, they must not be encoded in the physical constituents. If they are encoded in the physical constituents, then they must be predictable from them.
If these properties are not encoded in their physical constituents, where does the information come from and where is it represented?
Suggesting that the natural laws are such that all behavior must be entailed by "lower level" natural laws, is a stronger position than stating that all things follow natural law. I think it is hubristic to think that somehow our understanding of natural law is exempt from the same issues that are raised by the incompleteness theorem in math.
I would expect the answer would be "no". You would have to know about the environment that trained them, which blows the door open for something which is irreducible without knowing about environmental conditions, and biology having too rich of an environment to be as precisely reducible as computers might ever be without them being also a computer system.
In my other posts in this thread I emphasize the "in-principle" and "in-practice" distinction because I don't believe it is the "in-principle" part of reductionism that ought to be at stake. It's if we can actually do it in a way that doesn't invite approximations.
"More is Different: Broken symmetry and the hierarchical nature of science" http://robotics.cs.tamu.edu/dshell/cs689/papers/anderson72mo...
Science divides into different disciplines precisely because the units and laws of one model do not close over the phenomena of another.
Anderson is right to point out that reduction is easier than construction. I deny him the implication that construction is fundamentally impossible, only that it is out of reach of current human knowledge.
Nothing prevents a Demon from starting with first principles of natural laws and matter, sitting and pondering for infinity, and writing a treatise on any number of emergent phenomena, say: realpolitik between countries made up of parties made up of people made up of organic matter made up of atoms made up of...
We know this must be possible because it must have happened at least once, in the mind of the demon we call reality.
I get the distinction you're making between in-principle and in-practice, but this is an accident of our capabilities. Any gaps between the sciences is due to our ignorance. Sadly it seems human scientists desire to claim their corner of science is strong, independent and just as "fundamental" as any other's, and like playing up these gaps in our knowledge. I don't understand this desire to draw permanent boundaries based on arbitrary human limitations, and so quickly declare non-overlapping magesteria.
If it's a matter of the framing that makes you sombre, consider the alternative where being a finite observer with the capacity for self-reflection such as ourselves is put in a situation where we can navigate alternative descriptions of reality, never having to terminate with a final explanation, yet always growing in personal understanding... this is what your Demon would actually be doing, for if it were as powerful as you imply, it would not be a scientist at all. It would simply be reality, with these observers the lesser of it.
Heck below atoms, which lend themselves most strongly to the reductionist intuition, we have quantum waves. The wave-particle duality should at least simultaneously give reduction and non-reduction some credence.
Maxwell's Demon is new to me, and I'm not quite sure how to interpret it in this context. At first read, the claim that the observing, calculating, acting Demon, manipulating a physical trapdoor is not part of the thermodynamic system seems... laughable.
You don't have to posit the supernatural. People conflate believing in a single objective reality with having to believe in strong materialism (or worse, atomic materialism, when QM goes deeper), when all you have to do is believe that reality is consistent. You might not be able to create a total consistent model of reality, but if reality is consistent then you don't have to propose extra-physical forces due to conservation of energy or other such constraints. You can exclude contradictory hypotheses even if you can't settle on the "actual" one, even in-principle.
In which case you can have models in one domain of science, and models in another domain, which may not connect with each other, but they don't have to contradict each other either, and you can do this all while not believing in the supernatural or denying an objective reality.
That's the immediate refutation a lot of people propose, but then to model that demon plus the system is to also become another demon. So you can't escape this problem as long as you are not an abstract ideal observer, which none of us are in practice.
(The fact that it's laughable is correct, because it could never happen, including to us.)
The individual mind is far more complex than any existing programs. We are certainly not aware of all of the aspects of the world it is responding to. Furthermore, the diversity of those responses across the population is staggering. 'Irreducible' seems like the right adjective at present.
Issac Newton also believed in things we would laugh about and heck even back then were considered a laughing stock by scientists https://en.m.wikipedia.org/wiki/Isaac_Newton%27s_occult_stud...
You're taking what should be proven as a premise. He's only "flawed" if he's wrong, which is not really a closed case.
Besides, what's this "he doesn't have to have a reason" thing? He has a reason, and it's exactly the very arguments in TFA.
Anything particularly flawed about his argument in TFA (or him as a person)?
That said early QM had a lot of metaphysical stuff in it for example CCC had a pretty substantial following at the time due to some of the prominent people that supported it
https://en.m.wikipedia.org/wiki/Von_Neumann–Wigner_interpret...
However it’s highly unlikely that the Avon Neumann interpretation is correct given what we know about QM, in fact it was highly unlikely back when the interpretation was initially conjectured.
And this brings me to a personal anecdote I don’t believe that Consciousness Causes Collapse is a correct interpretation of quantum mechanics, I don’t actually have sufficient faculties to argue with someone like Von Neumann on this matter however it just sounds utterly stupid and rediculous to me that a consciousness would be required for QM effects to be manifested.
This is an utterly flawed and poorly constructed logic but I am most likely right in my assumption.
I don't think anyone here paid $40 to read it most people just know to go to SciHub and search for the article :)
If we’re talking about VSI/GAI or some sort of singularity event where people can upload their brains into a computer and remain conscious well then their definition would be which ever legal and common definition society would grant them.
There is absolutely nothing special about intelligence or consciousness and it’s an arbitrary definition in the first place which we put in due to fear of the unknown and our own physical limitations.
Anything beyond that is for the most part intellectual masturbation with little actual value or true insight that can be gained from it.
We created the definition for what is alive, conscious and intelligent based on our limited understanding of the universe and our human centric world view these definitions change as time changes just like every other arbitrary definition we have set in stone in the past.
Same goes for life which is why often we use the phrase life as we know it.
If a cloud of gas can do everything a brain can and we set an arbitrary set of rules of consciousness and it passes the benchmark then it’s conscious based on our arbitrary definition on a cosmic scale it’s still a cloud of dust just like we are lumpy specs of hydrated carbon.
There is no special meaning to life or to consciousness other than the former might be an intrinsic outcome of a universe with an entropy driven arrow of time, and the latter might be an intrinsic outcome of iterative natural selection of self assembling replicating strands of hydrated carbons and other organic molecules.
As far as Boltzmann brains go then a classical Boltzmann brain can actually be disproven even without going into the debate if there is even unbounded amount of randomness in the universe.
As for quantum Boltzmann brains then it’s not again freaky and it heavily is dependent on how you take on physicality.
If you think that the brain is a quantum system then a Boltzmann brain can never be a duplicate of you due to the no cloning theorem.
If the brain is not a QM system but a classical one which is more likely to be the case then classical Boltzmann brains aren’t really possible in our universe.
Overall this is again a philosophical niche not really physics it’s a fun anecdote to ponder not something you should take on seriously.
Now if you want to take evolution as a random activity despite it not being random then we are all Boltzmann brains but again as a whole a Boltzmann brain does not provide any insight into fundamental natural law or useful heuristics for emerging properties so it’s not as much freaky as well pointless.
It's somewhat arbitrary, but hardly utterly. If anything, not only it comes from direct experience, but is also the most constant experience we have.
(That's the point of Descartes cogito ergo sum, btw. We could doubt that the landscape arounds us that we see exists, but we can't really doubt that we think, for to doubt is itself part of thinking).
There is no single objective and useful definition for consciousness in philosophy or natural science other than the clinical definition of being aware and responsive to one's surroundings which technically mean that an ameba can be considered conscious since it's definitely aware of it's surroundings.
And even the clinical definition is arguably not very useful in the grand scheme of things because it does not deal with inanimate objects and the definition of life is murky at best.
So the best the best definition we have for consciousness is a clinical definition which is only applicable to life as we know it which has nothing to do with what ever you were talking about, hence utterly arbitrary.
There's nothing arbitrary about it. All of those ("thought", "doubt", "inner monolog") go hand in hand with consciousness in the common sense, and at worst case, they are phenomena that presuppose it (secondary effects).
It's also quite common in discussions regarding qualia for consciousness to include "self consciousness", not some low level awareness of surroundings that it's not aware of itself.
Else a Rumba is also conscious.
>And even the clinical definition is arguably not very useful in the grand scheme of things because it does not deal with inanimate objects and the definition of life is murky at best.
Well, everything's murky if you try hard enough. Still, aside from some corner cases (e.g. are viruses living, are robots?) life is as clear cut as things come.
>So the best the best definition we have for consciousness is a clinical definition which is only applicable to life as we know it which has nothing to do with what ever you were talking about
It makes sense it has "nothing to do" with what I was talking about, since that's a definition you brought forward here and put up as the "best" and single useful one.
It might be the simpler to test for, or the most useful for medical use. But it's even murkier than mine (since "awareness" itself reintroduces the issue). If we were to be content with low-level awareness then a Roomba is conscious, as it is in a way aware of its surroundings too.
When we discuss consciousness, qualia, etc, we go beyond this basic definition. That doesn't make it "utterly arbitrary" -- if that was the case any random definition would do.
Again an arbitrary definition based on a human centric view.
It's quite possible that we will develop an AI that would fall under what we would consider consciousness that has no inner monolog, on the other hand it's also quite possible that we'll develop AIs that come no where near consciousness with one.
Consciousness as you continue to use it is an utterly arbitrary and irrelevant definition you can set an arbitrary benchmark for any arbitrary type of consciousness you want this is simply defining heuristics which is while can be a useful tool in some cases is not natural law or anything other than arbitrary.
> Else a Rumba is also conscious.
And what would be the problem or wrong with that? If the definition that supports Rumba being a conscious contraption is a useful heuristic model for you then use it there is no wrong or right with arbitrary definitions there is just useful or not.
That, like the rest of the arguments, it would expand the reach of consciousness so much as to make it meaningless.
Like GP, I'm hoping someone with the time and inclination will summarise that argument for us.
The cutting edge of physics is often borderline metaphysical and well to a point nonsensical especially when you rely heavily on flawed thought expriements and unable to construct any good experimental ones.
Edit: am just a hobbyist at this stuff, I’m probably wrong ;)
> I cannot imagine how P could be true; therefore P must be false.
That's the gist of the argument. Of course, there is disagreement about what counts as a sufficient explanation or the best explanation at a time and others may disagree. It's philosophy of science, not science.
The article in the OP is about the argument that the explanation of characteristic biological functions by physics is impossible. Niel argues for epistemological anti-reductionism. It's not about throwing doubt on the assumption that reductionism is true, it is specifically arguing that it is in fact false using the analogy of the complementarity that governs the explanation of the stability of atoms.
So for example, Chalmers arguing that consciousness can't be reduced to physics is not an argument from incredulity. Rather, it's an argument that it's conceptually impossible. People might disagree with either Bohr or Chalmers arguments, but that's different from them committing this particular fallacy, unless it can be pointed out how Bohr or Chalmers were arguing from a failure of imagination.
Charmers argues that quaila cannot be reduced to physical causes. However we know for sure that any conceivable information or process that can be performed on information must be tractable to physical encoding.
It seems to me that qualia are simply information, or a process performed on information. If so, clearly they can have a physical cause. To refute this, Chalmers would have to show some property or characteristic of qualia that is not information or a process performed on it. But this is impossible. Any such explanation would by definition have to be encoded in information or a process performed on information.
Therefore if it is even possible for Chalmers to explain or adequately describe his thesis in a complete and consistent way, it must be true that his thesis is false.
Not all information has a subjective component to it, so qualia can't be identical to information, unless one is a panpsychist.
Moreover, information can be seen as an abstraction from experience that humans create via cognition and language. One might respond that all physical processes involve information, but physics is itself an abstraction. It's our attempt to create a map or models of the world. It's not the world itself.
Doesn't that just make qualia a subset of information, not distinct from it? Even metadata is still just a form of data.
That's taking what you ought to prove for granted.
We hardly know it "for sure". Even if we're totally certain of it, he haven't proved it.
https://www.youtube.com/watch?v=wwgQVZju1ZM
and his BBC version
Of _course_ biology won't be explainable using just the mathematics for basic physics. Quantum physics and classical physics are able to account for an enormous amount of the complexity of in the universe. However, their representation is so compressed, and has been developed and tested on such 'low dimensional' system, that there are surely mathematical laws that they simply cannot encode, nor should we expect them to.
The number of stable combinations of fundamental particles and the number of different orbital configurations etc. etc. are a set of rules with which everything 'must' be consistent (unless there is a major shift in our understanding of the fundamental laws of the universe). However, they give us little to no insight into what other constraints might be imposed on systems where the phenomena they describe are merely parts (yes I know that I have a wave function).
All this to say that it seems to me that there must be other mathematical laws that do not follow directly from 'basic' physics, that also constrain the behavior of more complex physical systems. The answer is not therefore that biology irreducible to some mathematical description, which is how I usually interpreted these arguments, but rather that there are additional mathematical laws that are needed. Perhaps that rather than despairing at the 'irreducibility' of biology to physics, we merely need to extend our notion of 'physics' to include the mathematical laws that constrain biology.
"Emphasis Mine"