I would agree. Usually in a larger scale the there simply are new questions, new relations and interactions that do not arise on the smaller scale. A metallurgist might know a lot about steel, aluminium and titanium, but from this knowledge you cannot make a supersonic aircraft.
This is also the reason why I emphasize examples where this logical problems arise somewhere else than in Quantum Mechanics as we can use mathematical models in many other situations.
This is very informative to me, thank you.
Iâve read about the meeting that Wittgenstein had with Turing and it seems that the two simply were talking a bit of different things. Although Wittgenstein understood the diagonal method and the Church-Turing thesis, I think he didnât understand the impact. And of course, this was the time before computers really had broken through and a âcomputerâ were indeed many times people making computations.
Iâm very drawn to the idea of the âparticipatory universeâ. It has come up in physicist John Wheelerâs work. But itâs important to understand what it does and doesnât say. Wheeler was a profound scientist - he coined the term âblack holeâ, among other things, and was teacher to Richard Feynmann and others. His âparticipatory universeâ and âit from bitâ analogy remain influential.
But what jumped out at me, was the similarity to a phrase I consistently noticed in John Vervaekeâs lecture series, Awakening from the Meaning Crisis. He speaks the âfour Pâs of knowingâ:
Propositional knowing â knowing that something is the case (facts, beliefs, declarative knowledge)
Procedural knowing â knowing how to do something (skills, tacit competence)
Perspectival knowing â knowing from a point of view (situational awareness, being in a context)
Participatory knowing â knowing through being in relationship with something (transformative, enacted, relational â the deepest level)
Vervaeke argues these are irreducible to one another, and that much of the Western tradition has over-privileged the propositional at the expense of the others â particularly participatory, which he connects to meaning-making and what he calls relevance realization.
Now, obviously, John Wheeler, and physics generally, knows nothing of this list, and I donât want to over-state the case. But I think the âparticipatoryâ dimension of knowing appears in physics in what Bitbol calls the âembodied activities of the scientistâ. When the scientist realises that she or he is an active participant not simply a detached spectator.
This is not âconsciousness causes collapseâ â Wheeler explicitly criticizes such ideas in his paper Law Without Law â but the realisation of the inherent limits of the âview from nowhereâ that characterised a lot of modern science.
(I also think that the particular area of science that has become acutely aware of the participatory role of the scientist is, of course, environmentalism, ecology, and wildlife preservation, although that is a bit tangential to the main thread.)
Yes, but a non-reductionist universe is harder to imagine than a reductionist one. I incidentally believe that even Newtonian mechanics isnât reductionist. For instance, you canât get the conservation laws from the properties of single particles. Rather, conservation laws seem to be properties of whole systems.
Youâre welcome. Iâm not an expert about the Church-Turing thesis but it wouldnât be an isolated case. Wittgenstein apparently also learned about Goedelâs theorems and didnât think of it about too much.
Anyway, there is a historical precedent of denying the whole talk about essences. Think about the Buddhist apoha theory, in which universals were denied and concepts used for classifications merely grouped things that lacked some differences instead of being used for grouping things that had properties in common: Apoha - Wikipedia *
Personally, I find the ânominalistâ approaches wanting because it does seem indeed that there are defining characteristics and entities can be grouped according to their common features.
from Wiki:
DignÄga defined apoha as a theory of classification based on exclusion. He said that a category such as âcowâ is arrived at not by the inclusion of all objects we would, based on some criteria, identify as cows, but by the exclusion of all objects we would identify as ânon-cows.â Concepts thus involve a double negation - the category of âcowâ is, in fact, the category of all ânot non-cows.â Since a negation or an absence cannot, according to the Buddhists, be objectively real (since absences are not caused and have no causal efficacy), this shows that concepts, though referring to a class of particulars, have no basis in reality.
Right, and I agree with that. But in the case of QM there is also the idea that the concepts that are used in the theory do not âmirrorâ something real. The wavefunction isnât a representation of something real like the âpoint particleâ of classical mechanics is supposed to be. What matters is that QM works.
So there are two insights here. The first which was already âimplicitâ even before QM was that a knowledge of how âphysical reality is in itselfâ is outside the scope of empirical knowledge. The second insight is that theory can make correct predictions even if they do not contain concepts that are supposed to ârepresentâ physical objects.
Jo Marchantâs book that the thread is about, is called âIn Search of Now.â And you know what doesnât exist without an observer? Now! The present is something that is only real for an observer. Relativity shows there is no absolute present. The present only exists in the awareness of individuals. I think this is also the conclusion of her book.
This perspective requires a completely different conception of time, from that which is standard or conventional. It requires that the future (or at least some aspects of it) has no physical existence, existing only as possibilities. This produces a significant problem, because it means that the physical world has to be recreated (in some sense), at each passing moment of time.
I donât think that this is an acceptable proposition. Interference patterns are empirically observable, directly with the eyes, as are other wave features like refraction and rainbows. This means that these waves which we observe with our eyes, just like sound waves, which we observe with our ears, must be physical waves. Sensation is of physical things. That the mind produces a nonphysical âprobability wavefunctionâ to represent the waves does not mean that the waves themselves are nonphysical. This is simply a manifestation of the difference between the representation (nonphysical) and what is represented (physical).
David Mermin, a supporter of QBism, actually wrote a paper about the âproblem of the Nowâ. Interestingly, it was considered a serious issue even by Einstein as his theories of relativity (both special and general) seem to imply that the passage of time is a perspectival illusion
Recognising that science is about the subject (the users of science) and not just about the object (the world external to that user) can eliminate well entrenched confusion in classical physics too ~ David Mermin
I donât see how the passage of time could be a perspectival illusion. That would mean that the subject would have to have something intrinsic to itself which makes the appearance of external things moving. How could the subject possibly be doing that? And even if that were the case, how would all the different subjects get their time passing systems in synch with each other? It seems very unrealistic.
Here are some snippets from the referenced article;
The problem of the Now will not be solved by discovering new physics behind that glowing point. Nor is it solved by dismissing the Now as an âillusionâ or as âchauvinism of the present moment.â It is solved by identifying the mistakes that lead us to conclude, contrary to all our experience, that there is no place for the Now in our physical description of the world.
To represent my actual experiences as a collection of mathematical points in a continuous space-time is a brilliant strategic simplification, but we ought not to confuse a cartoon that concisely attempts to represent our experience, with the experience itself
There is only one fundamental constraint on the Nows of two different people. When two people are together at a single event, if that event happens to be Now for either one of them, then it must be Now for them both. Like the Now of any single person, this is an obvious feature of human experience.
From the conclusion:
That there is such a thing as the present moment is an undeniably real part of the experience of every one of us. The fact that we have a useful formalism that represents our experience and seems not to contain a Now does not mean that Now is an illusion. It means that we must not identify the formalism with the experience that the formalism was constructed to describe.
Yes, I agree. And, indeed, many physicists donât agree with that reading of relativity.
I think it also provides an epistemic problem that would undermine science in general. If the ânowâ and change were illusory, then our experience would be completely illusory. If it is the case, how could any kind of empirical knowledge (science included) be reliable, then?
The problem with relativity theory is that it is utilitarian rather than truth motivated. After the heliocentric model of the solar system replaced the geocentric, Galileo realized that the same motions could be modeled from different reference frames, producing the same predictive results. Relativity was derived from this insight, as a pragmatic principle. We donât need to know the truth about motions in order to make accurate predictions.
Einstein introduced the speed of light into relativity theory as a constant, through the stipulation that simultaneity is relative. (The lightening/train example; there is no truth about whether the two lightening bolts struck the train at the same time, simultaneity is frame dependent). This is special relativity. The truth about ânowâ is sacrificed in order to integrate light into relativity theory, as something constant relative to classical relativity theory.
Relativity theory becomes a problem when people start to think that it provides us with the truth, or that it is the truth. The opposite is the case. It was intentionally designed by Galileo, based on the fundamental principle that truth is not required for modeling motions. So if we take that principle, motions are relative, as âthe truthâ, then the truth is that there is no truth about motions. This leads to ontologies like model-dependent realism, and Many-Worlds.
What I think is that it creates a separation between what we know from direct experience (as stated in your referenced article, that there is a real difference between past and future), and what we know through science. This is definitely âan epistemic problem that would undermine scienceâ. The scientific method intends to verify theories through empirical evidence. But if a principal âscientificâ theory (relativity) is unverifiable empirically, and actually designed to be contrary to fundamental experience, along with the intuition of âreal truthâ, and the desire for that, then it creates a separation, a gap within the domain of empirical knowledge.
See how this frames the pain felt by Bob is an item, as if it were a thing that could be moved from Bob to Alice? That framing is what Wittgenstein is dismissing.
However, even though Alice canât feel Bobâs pain, she will presumably know what it means to feel pain. So, what is the point?
Also bear in mind where the âAlice and Bobâ talk originated - with explanatory examples of the apparent paradoxes of observations in quantum physics. Here the cardinal difference is that the subject of the discussion is not âpainâ, which is first-person as a matter of definition, but observations, which prior to quantum physics were always thought to be perfectly objective.
Actually, Wittgenstein argues explicitly in âPhilosophical Investigationsâ, 253, that depending on the criterion of identity, two people truly can feel the same pain.
253. âAnother person canât have my pains.ââWhich are my pains? What counts as a criterion of identity here? Consider what makes it possible in the case of physical objects to speak of âtwo exactly the sameâ, for example, to say âThis chair is not the one you saw here yesterday, but is exactly the same as itâ.
In so far as it makes sense to say that my pain is the same as his, it is also possible for us both to have the same pain. (And it would also be imaginable for two people to feel pain in the sameânot just the correspondingâplace. That might be the case with Siamese twins, for instance.)
I have seen a person in a discussion on this subject strike himself on the breast and say: âBut surely another person canât have THIS pain!ââThe answer to this is that one does not define a criterion of identity by emphatic stressing of the word âthisâ. Rather, what the emphasis does is to suggest the case in which we are conversant with such a criterion of identity, but have to be reminded of it
It is not so poor when we think that meaning can be transmited but experience cannot. If we consider, for example, the scientific community, we must note that it is a community of meaning, and not of experience (unless the experience is already imbued with meaning). Furthermore, if we place ourselves at the heart of quantum mechanics, we must ask: is the role of experience really so essential? Yet another argument against the subjective idealism of quantum physics: the universality of quantum physicsâ discoveries, in terms of meaning and significance, must transcend experience, which is always particular.
That is why experiments are set up under conditions of repeatability and reproducibility, something which experienceâalways particularâcannot provide. Experiments are designed so that meaning, as something ideal and repeatable, can take place as the same; subjective experience is secundary.
âNot to mention how this scientific community is shaped and educated by meaning (language): the scientist learns to interpret through their training (learning the meaning of scientific practices) and, above all, learns to perceive with some meaning.
The possibility of science lies beyond subjective experience. Its possibility lies, as theory (theorein), in meaning.
The repeatability of experiments doesnât demonstrate that experience has been eliminated from physics â it demonstrates that the conditions under which experience occurs have been standardised. Repeatability is an intersubjective achievement: it still requires observers to set up apparatus, read results, and agree on outcomes. The universality of experimental findings is built out of a community of experiencing subjects coordinating their observations, not arrived at by transcending experience altogether.
As Michel Bitbol points out, inferring from the ideality of experimental results to the dispensability of experience is precisely the move that smuggles in a âview from nowhereâ â a third-person standpoint that tacitly presupposes what it claims to have demonstrated.
And thereâs even experimental evidence that undercuts the repeatability argument. The Wignerâs Friend scenario while originally a thought experiment â was realised in the lab by Proietti et al. at Heriot-Watt in 2019. The results showed that two observers can produce irreconcilable accounts of the same experimental outcome â and that both observations can be equally valid. Notably, the experimenters themselves observed that the scientific method relies on facts established through repeated measurements agreed upon universally â and then their own results undermined precisely that assumption.
So repeatability doesnât dissolve the observer; it presupposes one. See this link.
Which is not at variance with the QBist account but is just as predicted.
Iâll also explain what I mean by idealism. I donât mean that the world exists in the mind, nor that the mind or âmind-stuffâ is in any sense a constituent of the world. I mean that any conception or perception we have of the world is in some fundamental sense observer-dependent - and that this is something of which we are not generally aware, and which cannot be disclosed by empirical observation. So we do not see the world as it would really be without any observer in it, even if we can reliably infer and model that. And furthermore this is what the âobserver problemâ in quantum physics has shown to be the case. As Chris Fuchs has said in relation to QBism:
The very idea of science from the usual point of view is to take out everything to do with human subjectivity and see what remains. QBism says, if you take everything out of quantum theory to do with human subjectivity, then nothing remains.
I donât see your point. My point was that there are indeed situations in which we are able to recognize the limitations of our empirical knowledge. So, the knowledge that science give us of âphysical realityâ might be limited in an analogous (not identical) way in which our knowledge of the mental states of others is (the fact that we have empathy seems to suggest indeed that we do have some knowledge of the otherâs mental states).
