In this post she sums up beautifully what I and many physicists believe, and is vehemently opposed by the prevailing realist crowd here on LW. A few excerpts:
Look, I am a scientist. Scientists don’t deal with beliefs.
Can you point out a specific an example of “the prevailing realist crowd here on LW” or, if you don’t want to unfairly single out a specific example, concoct a charitable facsimile? (The fragment “is vehemently opposed by the prevailing realist crowd here on LW” seems hostile, I’d guess due to frustration, but I’m uncertain so I’m curious as to the relevant motivations for you to use it.)
Obviously scientists deal with beliefs. You’re claiming (and I believe you) that both you and “many physicists” don’t believe that philosophical realism is true (or ‘true’) or useful (or that it’s a ‘wrong question’). And, presumably, you and Sabine both believe that the theory that predicts that Higgs-bosons ‘exist’ is the best available theory for predicting anticipated experiences.
Maybe I’ve been drinking the Kool-Aid David Chapman’s been giving away for too long, but obviously, being something inside { reality / the universe } I have no privileged access to whether any particular beliefs are ultimately or perfectly true or that the objects of those beliefs are likewise ultimately or perfectly real. But if sure seems like we’ve been able to get closer and closer to true beliefs about what’s real. On the gripping hand, we also seem ‘doomed’ to run up against the inevitable nebulosity of our beliefs.
So, I’ll try to answer the questions that both you and Sabine seem to find so frustrating:
Does the Higgs-boson exist? – Yes, it seems to exist (i.e. to be a real particle). We have pretty strong evidence that it’s been detected and the evidence strongly suggests that its properties match our predictions.
Do black holes exist? – Yes, they seem to exist. We’ve even been able to recently generate an image of one (relatively) nearby!
Do quarks exist? – The best theory of particle physics suggests that they do but currently we don’t expect to be able to observe them ‘freely’, i.e. not bound within other less elementary particles, with our available tools, so the evidence of their existence is more indirect than we may otherwise hope to someday have.
Does time exist? – Yes, in the sense that we don’t have much of an ability to understand anything without, essentially, assuming it exists, tho we do know, and have strong evidence thereof, that it’s weirder than our intuitions would otherwise lead us to believe (e.g. it can ‘dilate’, even in ways we can precisely measure, in certain circumstances). But there are somewhat plausible ideas by which time may not be ‘ontologically primitive’ relative to some deeper understanding of the (observable) universe, e.g. timeless physics.
Do gravitational waves exist? Yes, they same to exist, and we have evidence that’s consistent with their existence according to our best theories of physics.
Sabine wrote:
Look, I am a scientist. Scientists don’t deal with beliefs. They deal with data and hypotheses. Science is about knowledge and facts, not about beliefs.
That’s just wrong. There is no knowledge, there are no facts, there is no data, nor hypotheses, divorced from or somehow separate from beliefs. It’s a belief that facts, or knowledge about them, exist, that statements of or about them are true. Indeed, I don’t know what a fact is or what knowledge could be if they were not also true. A statement of fact can be false, i.e. not true, i.e. a statement of something that is not a fact.
Sabine’s last paragraph:
Here is a homework assignment: Do you think that I exist? And what do you even mean by that?
You seem to be arguing that the correct answer is no, Sabine Hossenfelder doesn’t exist. I know of no theory, and definitely no mathematical framework, that predicts (specifically or even in general possibility) that she does. According to the best theories of physics there are only quantum fields and space-time. QED
Except, that’s silly – of course she exists (and is real), at least as far as I can tell!
I think I may have demonstrated that I’m not in fact a philosophical realist. But I think that’s wrong too. I strongly suspect that the universe (reality) is ontologically independent of my, or anyone else’s, consciousness, or any ideas, beliefs, facts, or knowledge we may have with regard to it. I’m pretty sure we haven’t measured or observed any such ontologically primitive elements, and I’m agnostic as to whether we (or anything else in the universe) will ever be able to do so. I wouldn’t be surprised if it was actually impossible to do so. But I do believe they’re real and that they exist.
As to everything else tho, e.g. the Higgs-boson, quarks, black holes, let alone planets, species, individual people – obviously those are not ontologically primitive and so the degree to which they are ‘real’ and ‘exist’ is nebulous. (Unless of course Platonic realism/idealism, or mathematicism, is true (or maybe even also true), in which case everything imaginable (and more) ‘exists’ and is ‘real’.)
Look, I am a scientist. Scientists don’t deal with beliefs
That’s absurdly wrong under some interpretations of “belief”. I would assume that what Sabine means by belief is some combination of certainty and not being based on evidence.
obviously those are not ontologically primitive and so the degree to which they are ‘real’ and ‘exist’ is nebulous
It’s not obvious that being complex or a compound makes something less real.
I’m not sure what conceptions of ‘belief’ you have in mind in the first part of your reply. Are you claiming tho that Sabine, and other physicists, as shminux claims, don’t have beliefs as would be commonly understood? Even about physics, or the accuracy of the mainstream theories in that field? I admit to being confused as to exactly what point shminux, or Sabine, are trying to make tho.
I would assume that what Sabine means by belief is some combination of certainty and not being based on evidence.
I find it hard to imagine what Sabine or shminux could have in mind if what you write is true. They, apparently, would claim that the some physics theories are accurate. In what sense do those claims not correspond to beliefs, e.g. that the theories actually are accurate?
Maybe you’re on to something about this whole discussion being confusing because the participants, particularly Sabine or shminux, aren’t explicitly discussing degrees of certainty or amounts and strength of evidence. For example, it certainly seems completely reasonable to reply to “Do black holes exist? Are they real?” with something like “They’re predicted by our best theories of physics and we have pretty strong indirect evidence of their existence, in specific places (in space-time), so we’re reasonably certain that they do in fact exist and are real. For one, we’ve generated an image of one that’s relatively nearby and all the methods we used to do so seem, as far as we can tell, to be eminently reasonable based on everything else we know (and believe to be true).”.
It’s not obvious that being complex or a compound makes something less real.
Sure, if by “the Higgs-boson, quarks, black holes, let alone planets, species, individual people” we ‘only meant’ something like a (Vast) group of quantum field excitations (or similar). But, as far as I can tell, we mean very different things by each of those different words or phrases. It seems pretty obvious to me that the ‘reality’ of a species is a very different thing than the reality of an individual, and neither are always clear in every situation. During speciation, it’s not clear when one species has become many – so the ‘reality’ of the species, one or many, seems less real to me, in that specific situation anyways. Similarly, victims of brain trauma are often described as ‘like another person’ – that seems to clearly infringe on the ‘reality’ of personal identity, which seems like a pretty important component of personhood. Generally, the degree to which a concept or category is nebulous seems to match how ‘real’ it is, or seems.
They, apparently, would claim that the some physics theories are accurate. In what sense do those claims not correspond to beliefs, e.g. that the theories actually are accurate?
These claims-to-accuracy are not beliefs in the sense that they are based on evidence and are subject to revision, and are therefore not certain.
It seems pretty obvious to me that the ‘reality’ of a species is a very different thing than the reality of an individual,
There may be some issues about the classification or demarcation of complex entities , but they are not necessarily the same as issues about the existence of entities.
For instance, there was confusion about whether the platypus was a mammal or marsupial, but no dou t that they exist.
These claims-to-accuracy are not beliefs in the sense that they are based on evidence and are subject to revision, and are therefore not certain.
That seems like a really tortured definition/interpretation/understanding of ‘belief’. What’s the motivation for that? To distinguish these “claims-to-accuracy” as different than religious belief? I’m confused why this rhetorical stance is useful or interesting given that even religious belief is based on evidence and subject to revision, and even very few religious believers claim total or complete certainty.
There may be some issues about the classification or demarcation of complex entities , but they are not necessarily the same as issues about the existence of entities.
I agree with respect to classification but not for demarcation – if it’s unclear how to demarcate two entities isn’t it unclear whether two entities exist (versus one or none)?
And generally, because of the seemingly inevitable issues with demarcating individual entities of a given class, it’s less clear that they exist, or the reality of their existence (as entities of that class) seems less obvious, i.e. they are ‘less real’.
I’m suggesting that ‘is real’ and ‘exists’ are not binary values but rather magnitudes. Unicorns seem pretty clearly ‘not real’ and that it is true that they ‘do not exist’ (and never existed). But the magnitude of their reality or non-existence is not perfectly un-real or non-existent, as even something folk tales that mention them is (very) weak evidence that they might be real or might have existed (or might still exist somewhere).
Here are two of my favorite examples of categories of entities that are somewhat unreal or less ‘existential’:
Tectonic plates
The species of dogs, wolves, and coyotes
For tectonic plates, it’s not obvious how many exist, thus the existence of some possible plates is uncertain. Obviously the components of plates exist but, at least for some (possible) plates, it’s not clear that they do exist or are ‘real’ – as tectonic plates.
And dogs, wolves, and coyotes can all interbreed, and produce sexually fertile offspring, and genetic evidence of existing (individual) dogs, wolves, or coyotes indicate that they are all genetically intermixed. Are those species real? Do those species exist? Surely, in general, the individual members of those species exist, but do the species themselves exist? Are those species ‘real’? It seems clear to me that the ‘reality’ of those three species is strictly less than the reality of any members of those species.
I wasn’t trying to attack you, or Sabine or shminux either, so I’m sorry if seemed that way to you.
I think I understand their position pretty well – all of the questions they supposedly face about whether the objects of study are ‘real’ or whether they ‘exist’ are almost certainly frustrating. Obviously all of those objects are real enough, or likely enough to exist, in the sense that a sufficient cumulative weight of evidence exists and is accepted, for it to be almost entirely uncontroversial for professional physics to study them. On one end of professional practice of their field, just studying the relevant mathematics is a perfectly accepted practice in and of itself. On the other end, there’s sufficient observational evidence, especially given the corresponding (accepted) theoretical interpretations, that the study of these objects is by itself relatively mundane and unremarkable.
The annoying real/exists questions are almost certainly interpreted as critical, if not negative, judgements implying that the physicists at whom the questions are addressed are either stupid or naive, or maliciously deceptive, for believing the objects of study as being (sufficiently) real or existing. So I’d expect an almost overwhelming urge for them, the physicists, to want to avoid dealing with such questions or otherwise to be able to themselves imply or aver that such questions are stupid or naive, or even unanswerable (and thus not ‘scientific’, i.e. worthy of their consideration).
And I’m sure some (small) degree of ill will, on both the part of physicists and the real/exist questioners, is warranted. Asking whether the object of someone’s studies are real or whether they exist is almost unavoidably derogatory. And surely some physics will turn out not to have been about or in search of anything that could reasonably be believed to be real or to exist, as has happened many times before.
That seems like a really tortured definition/interpretation/understanding of ’belief
If there is an ambiguity in natural language, then an attempt unpick it will look unnatural.
Consider a situation where two theories are equally supported by evidence. If a physicist backs theory A over theory B that would be the kind of belief that Sabine is rejecting.. I think.
I agree with respect to classification but not for demarcation – if it’s unclear how to demarcate two entities isn’t it unclear whether two entities exist (versus one or none)?
In this and your other examples, one can adopt an arbitrary classification scheme, and then the question of whether the posits of the scheme exist can be settled straightforwardly. So problems of existence are not problems of existence per se but problems of classification.
I’m confused:
Can you point out a specific an example of “the prevailing realist crowd here on LW” or, if you don’t want to unfairly single out a specific example, concoct a charitable facsimile? (The fragment “is vehemently opposed by the prevailing realist crowd here on LW” seems hostile, I’d guess due to frustration, but I’m uncertain so I’m curious as to the relevant motivations for you to use it.)
Obviously scientists deal with beliefs. You’re claiming (and I believe you) that both you and “many physicists” don’t believe that philosophical realism is true (or ‘true’) or useful (or that it’s a ‘wrong question’). And, presumably, you and Sabine both believe that the theory that predicts that Higgs-bosons ‘exist’ is the best available theory for predicting anticipated experiences.
Maybe I’ve been drinking the Kool-Aid David Chapman’s been giving away for too long, but obviously, being something inside { reality / the universe } I have no privileged access to whether any particular beliefs are ultimately or perfectly true or that the objects of those beliefs are likewise ultimately or perfectly real. But if sure seems like we’ve been able to get closer and closer to true beliefs about what’s real. On the gripping hand, we also seem ‘doomed’ to run up against the inevitable nebulosity of our beliefs.
So, I’ll try to answer the questions that both you and Sabine seem to find so frustrating:
Does the Higgs-boson exist? – Yes, it seems to exist (i.e. to be a real particle). We have pretty strong evidence that it’s been detected and the evidence strongly suggests that its properties match our predictions.
Do black holes exist? – Yes, they seem to exist. We’ve even been able to recently generate an image of one (relatively) nearby!
Do quarks exist? – The best theory of particle physics suggests that they do but currently we don’t expect to be able to observe them ‘freely’, i.e. not bound within other less elementary particles, with our available tools, so the evidence of their existence is more indirect than we may otherwise hope to someday have.
Does time exist? – Yes, in the sense that we don’t have much of an ability to understand anything without, essentially, assuming it exists, tho we do know, and have strong evidence thereof, that it’s weirder than our intuitions would otherwise lead us to believe (e.g. it can ‘dilate’, even in ways we can precisely measure, in certain circumstances). But there are somewhat plausible ideas by which time may not be ‘ontologically primitive’ relative to some deeper understanding of the (observable) universe, e.g. timeless physics.
Do gravitational waves exist? Yes, they same to exist, and we have evidence that’s consistent with their existence according to our best theories of physics.
Sabine wrote:
That’s just wrong. There is no knowledge, there are no facts, there is no data, nor hypotheses, divorced from or somehow separate from beliefs. It’s a belief that facts, or knowledge about them, exist, that statements of or about them are true. Indeed, I don’t know what a fact is or what knowledge could be if they were not also true. A statement of fact can be false, i.e. not true, i.e. a statement of something that is not a fact.
Sabine’s last paragraph:
You seem to be arguing that the correct answer is no, Sabine Hossenfelder doesn’t exist. I know of no theory, and definitely no mathematical framework, that predicts (specifically or even in general possibility) that she does. According to the best theories of physics there are only quantum fields and space-time. QED
Except, that’s silly – of course she exists (and is real), at least as far as I can tell!
I think I may have demonstrated that I’m not in fact a philosophical realist. But I think that’s wrong too. I strongly suspect that the universe (reality) is ontologically independent of my, or anyone else’s, consciousness, or any ideas, beliefs, facts, or knowledge we may have with regard to it. I’m pretty sure we haven’t measured or observed any such ontologically primitive elements, and I’m agnostic as to whether we (or anything else in the universe) will ever be able to do so. I wouldn’t be surprised if it was actually impossible to do so. But I do believe they’re real and that they exist.
As to everything else tho, e.g. the Higgs-boson, quarks, black holes, let alone planets, species, individual people – obviously those are not ontologically primitive and so the degree to which they are ‘real’ and ‘exist’ is nebulous. (Unless of course Platonic realism/idealism, or mathematicism, is true (or maybe even also true), in which case everything imaginable (and more) ‘exists’ and is ‘real’.)
That’s absurdly wrong under some interpretations of “belief”. I would assume that what Sabine means by belief is some combination of certainty and not being based on evidence.
It’s not obvious that being complex or a compound makes something less real.
I’m not sure what conceptions of ‘belief’ you have in mind in the first part of your reply. Are you claiming tho that Sabine, and other physicists, as shminux claims, don’t have beliefs as would be commonly understood? Even about physics, or the accuracy of the mainstream theories in that field? I admit to being confused as to exactly what point shminux, or Sabine, are trying to make tho.
I find it hard to imagine what Sabine or shminux could have in mind if what you write is true. They, apparently, would claim that the some physics theories are accurate. In what sense do those claims not correspond to beliefs, e.g. that the theories actually are accurate?
Maybe you’re on to something about this whole discussion being confusing because the participants, particularly Sabine or shminux, aren’t explicitly discussing degrees of certainty or amounts and strength of evidence. For example, it certainly seems completely reasonable to reply to “Do black holes exist? Are they real?” with something like “They’re predicted by our best theories of physics and we have pretty strong indirect evidence of their existence, in specific places (in space-time), so we’re reasonably certain that they do in fact exist and are real. For one, we’ve generated an image of one that’s relatively nearby and all the methods we used to do so seem, as far as we can tell, to be eminently reasonable based on everything else we know (and believe to be true).”.
Sure, if by “the Higgs-boson, quarks, black holes, let alone planets, species, individual people” we ‘only meant’ something like a (Vast) group of quantum field excitations (or similar). But, as far as I can tell, we mean very different things by each of those different words or phrases. It seems pretty obvious to me that the ‘reality’ of a species is a very different thing than the reality of an individual, and neither are always clear in every situation. During speciation, it’s not clear when one species has become many – so the ‘reality’ of the species, one or many, seems less real to me, in that specific situation anyways. Similarly, victims of brain trauma are often described as ‘like another person’ – that seems to clearly infringe on the ‘reality’ of personal identity, which seems like a pretty important component of personhood. Generally, the degree to which a concept or category is nebulous seems to match how ‘real’ it is, or seems.
These claims-to-accuracy are not beliefs in the sense that they are based on evidence and are subject to revision, and are therefore not certain.
There may be some issues about the classification or demarcation of complex entities , but they are not necessarily the same as issues about the existence of entities.
For instance, there was confusion about whether the platypus was a mammal or marsupial, but no dou t that they exist.
That seems like a really tortured definition/interpretation/understanding of ‘belief’. What’s the motivation for that? To distinguish these “claims-to-accuracy” as different than religious belief? I’m confused why this rhetorical stance is useful or interesting given that even religious belief is based on evidence and subject to revision, and even very few religious believers claim total or complete certainty.
I agree with respect to classification but not for demarcation – if it’s unclear how to demarcate two entities isn’t it unclear whether two entities exist (versus one or none)?
And generally, because of the seemingly inevitable issues with demarcating individual entities of a given class, it’s less clear that they exist, or the reality of their existence (as entities of that class) seems less obvious, i.e. they are ‘less real’.
I’m suggesting that ‘is real’ and ‘exists’ are not binary values but rather magnitudes. Unicorns seem pretty clearly ‘not real’ and that it is true that they ‘do not exist’ (and never existed). But the magnitude of their reality or non-existence is not perfectly un-real or non-existent, as even something folk tales that mention them is (very) weak evidence that they might be real or might have existed (or might still exist somewhere).
Here are two of my favorite examples of categories of entities that are somewhat unreal or less ‘existential’:
Tectonic plates
The species of dogs, wolves, and coyotes
For tectonic plates, it’s not obvious how many exist, thus the existence of some possible plates is uncertain. Obviously the components of plates exist but, at least for some (possible) plates, it’s not clear that they do exist or are ‘real’ – as tectonic plates.
And dogs, wolves, and coyotes can all interbreed, and produce sexually fertile offspring, and genetic evidence of existing (individual) dogs, wolves, or coyotes indicate that they are all genetically intermixed. Are those species real? Do those species exist? Surely, in general, the individual members of those species exist, but do the species themselves exist? Are those species ‘real’? It seems clear to me that the ‘reality’ of those three species is strictly less than the reality of any members of those species.
Note that I am not defending Sabine’s usage, just trying to understand it.
I wasn’t trying to attack you, or Sabine or shminux either, so I’m sorry if seemed that way to you.
I think I understand their position pretty well – all of the questions they supposedly face about whether the objects of study are ‘real’ or whether they ‘exist’ are almost certainly frustrating. Obviously all of those objects are real enough, or likely enough to exist, in the sense that a sufficient cumulative weight of evidence exists and is accepted, for it to be almost entirely uncontroversial for professional physics to study them. On one end of professional practice of their field, just studying the relevant mathematics is a perfectly accepted practice in and of itself. On the other end, there’s sufficient observational evidence, especially given the corresponding (accepted) theoretical interpretations, that the study of these objects is by itself relatively mundane and unremarkable.
The annoying real/exists questions are almost certainly interpreted as critical, if not negative, judgements implying that the physicists at whom the questions are addressed are either stupid or naive, or maliciously deceptive, for believing the objects of study as being (sufficiently) real or existing. So I’d expect an almost overwhelming urge for them, the physicists, to want to avoid dealing with such questions or otherwise to be able to themselves imply or aver that such questions are stupid or naive, or even unanswerable (and thus not ‘scientific’, i.e. worthy of their consideration).
And I’m sure some (small) degree of ill will, on both the part of physicists and the real/exist questioners, is warranted. Asking whether the object of someone’s studies are real or whether they exist is almost unavoidably derogatory. And surely some physics will turn out not to have been about or in search of anything that could reasonably be believed to be real or to exist, as has happened many times before.
If there is an ambiguity in natural language, then an attempt unpick it will look unnatural. Consider a situation where two theories are equally supported by evidence. If a physicist backs theory A over theory B that would be the kind of belief that Sabine is rejecting.. I think.
In this and your other examples, one can adopt an arbitrary classification scheme, and then the question of whether the posits of the scheme exist can be settled straightforwardly. So problems of existence are not problems of existence per se but problems of classification.