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All I can say about this as a dude with a doctorate in physics and an interest in foundations is: I guess, dude, if this is how you want to live your life. It

All I can say about this as a dude with a doctorate in physics and an interest in foundations is: I guess, dude, if this is how you want to live your life. It isn't that I agree with the person who wrote Asimov the letter (in fact, based on his description, I frankly wonder if the letter writer wasn't my father). Its just that there is something subtly wrong with Asimov's view of the progress of scientific knowledge. At least its extremely instrumentalist. If we think of knowledge as a sort of temporary mental state which lives between setting up a physical state and making a measurement, then, yes, knowledge has progressed in exactly the way that Asimov is saying. And that is nothing to sneeze at. But like consider quantum mechanics. People still cannot make heads or tails of what the ontology of quantum mechanics is, despite some compelling stories. And that makes perfect sense since QM is not compatible with special or general relativity! So its dumb to try and make sense of what QM tells us about what is. So why not try to understand what the ontology of QFT is? This seems reasonable, since QFT is capable of making correct predictions (at least in the scattering regime) and is invariant. But no one on earth can write down a coherent mathematical theory of QFT, so interpretation is even more difficult than QM. And this is yet to even try to tackle with conceptual gap between GR and QM/QFT, where we genuinely are perplexed but at least have good reason to think that the final interpretation of QM or spacetime has to have something to do with the way that the two theories interact. From this point of view as our ability to connect experiment with outcome has increased our ability to actually say what it is we are even talking about outside of the purely instrumental has decreased since the 19th Century. Back then we though we knew that there were atoms or electrons or whatever. Light waves or photons. Now, I would argue very strenuously, we genuinely have no understanding at all of what those things are outside of a set of purely instrumental definitions which leave a lot to be desired. My personal understanding here is that really there are no electrons, photons, quantum fields, masses, gravity. There is just the single substance of the universe which we have learned to manipulate and predict with ever improving precision (in limited cases). Maybe that is knowledge? Doesn't always feel like it.

kitchi 1y ago
As another dude with a doctorate in Physics, I have to disagree with you (at least somewhat). > From this point of view as our ability to connect experiment with outcome has increased our ability to actually say what it is we are even talking about outside of the purely instrumental has decreased since the 19th Century. Back then we though we knew that there were atoms or electrons or whatever. Light waves or photons. Now, I would argue very strenuously, we genuinely have no understanding at all of what those things are outside of a set of purely instrumental definitions which leave a lot to be desired. I disagree with this entirely. The existence of QFT, and our knowledge of the inconsistency between say GR and the quantum realm does not negate the idea of photons and electrons as real, measurable quantities. The fact that we have GR does not negate the fact that we still use Newtonian gravity in regimes where it is sufficiently accurate. All the new knowledge we have learned still is (and absolutely must be) consistent with our old knowledge that has been proven correct in the regimes that they were proven correct. This is effectively what Asimov is saying (as I understand anyway) - the knowledge that the Earth is a sphere does not invalidate the assumption that the Earth is flat approximately and locally. I would also argue that the only things we can "know" are what you call the instrumental definitions. We only know what we measure. The rest is interpretation, and self-consistent understanding. String theory can tell me that we have several dimensions etc but until we have a way to measure and check it remains a conceptual framework to make predictions, rather than a description of how things really are. GR is much closer to a description. It told us about the precession of mercury, it told us to account for time dilation so we can use GPS satellites. It also predicted black holes, which were conceptually consistent but it's only been in the last ~ 5 years that we have the closest thing yet to experimental verification with the Event Horizon Telescope and gravitational wave measurements. If another theory comes along and explains all of GR with a different explanation for black holes, we will need still more accurate measurements to discriminate between the two theories. Knowledge is only as accurate as we can measure.
- glenstein 1y ago
  I agree much more with your approach. The way I've heard it best described is these notions of electrons and photons etc will still be retained as a special case of whatever theory supersedes them, which is critical, because that's at the heart of the "relativity of wrong" argument. Some take the prospect of a future revision of theories to mean our present state of knowledge is no different than any prior failed theory, which I think is an urgently, catastrophically wrong, catastrophically confused way to regard the history of scientific knowledge.
- nathan_compton 1y ago
  I don't think you get my point because I don't think of anything you are saying as having anything to do with what I was saying. If you have a purely instrumentalist view of reality, where, as I said, your so-called knowledge is actually just a model of an unknown thing which you employ to predict the measurements you read out against a ruler or on a meter or something, then yes, we've made progress exactly of the kind you describe. But I was trying to make a point about epistemology and ontology. Physics has actually been pretty catastrophic for ontology. I don't think its wrong to say that from the point of view of physics we simply do not know what anything actually is. > I would also argue that the only things we can "know" are what you call the instrumental definitions. We only know what we measure. The rest is interpretation, and self-consistent understanding. Yes. But this is a fairly radical position historically and philosophically. Most people would say that there is more to existence than measurement and I while I share your instrumentalist sympathies, like most physicists, I don't see the philosophical case that we can have a consistent worldview if we denounce all knowledge not related to measurement as a total non-starter. Think about what instrumentalism really means. When you utter the sentence the earth is an oblate spheroid, you are actually making an incredibly complicated set of statements about the outcomes of experiments. If we take the instrumentalist view the measurement doesn't actually tell us the earth is an oblate spheroid - it just tells us that if we make a series of measurements then they come out in such a way as to be concordant with a model of the earth as an oblate spheroid. Are you really prepared to give up the idea that the earth is a thing you can know about? I actually rather think physics strongly encourages us to adopt the instrumentalist view, primarily because it seems so clear that physics has a local character. In GR there simply is no state of affairs whatever about what is happening "right now" except at the point in spacetime where you make a measurement. Really think about what that means. If we are standing at the north pole and make a measurement of some kind, how can it pertain to the earth as a distributed object in space when we know GR says there is no state of affairs pertaining to that object at the moment of the measurement? GR tells us all about what the outcome of various measurements will be, but it also calls into question what precisely those measurements might mean. The instrumentalist is committed to the idea that the only thing we can talk about is the results of measurements. What the measurements operate on is just not something we can know. I think that's weird. Physicists often conflate their mathematical models with reality and that lets them think an instrumentalist view is sufficient: the measurements coming out such and such a way is taken as evidence that the universe is filled with objects consistent with the model. But that association is non-trivial in modern physics.
the_af 1y ago
Your answer here puzzles me. It seems as if you intended it to disagree with Asimov, while in practice you actually agree with him and disagree with the English Lit professor?
- nathan_compton 1y ago
  Yeah, I'm not disagreeing with Asimov at all, I just think his characterization of physics as constituting knowledge is overly enthusiastic. Like, yes, its clear physics constitutes knowledge of some sort, but I think its much less knowledge of what things actually are than Asimov might be prepared to entertain. The reason I raise the point is that its at least conceivable that we could have found ourselves in a world where physics discovered a fundamental ontology of the universe. Eg, maybe we could have discovered that quantum fields could be consistently described at all scales and thus we could more definitively say "yes, Virginia, the universe is composed of quantum fields." But we did not find this. Quantum Fields are widely understood to be effective descriptions of some unknown phenomenon which may not even resemble anything which makes intuitive sense with the rest of the way we think about physics. And all of that is to say nothing about quantum mechanics or quantum gravity. This isn't a trivial observation. We seemed to know more and more about the ontology of the world up to and perhaps slightly after the annus mirabilis. Simply establishing that atoms existed was a sort of ontological climax which then unraveled into a flaccid denouement as quantum mechanics and then QFT and the inability to formulate quantum gravity cast deep doubt on what things are even made of or whether its even possible to conceive of things at all. I stress again, this might not have happened. I can imagine some possible world where t'Hooft like cellular automata were somehow confirmed and the question of ontology was well and truly put to bed or at least for any but the most extreme philosophical skeptics.
  - the_af 1y ago
    But aren't you essentially arguing that, indeed, there's wrong and there's wronger, and refuting the English professor who seemed to argue that "everyone is wrong but until shown this they are convinced they are right, therefore all knowledge is impossible"? (i.e. a slightly less new age version of "everything is relative!"). In other words, that Asimov is saying 2+2=5, while the English professor is saying "there's not difference between 5 and 'purple' as an answer!". In other words, don't you agree with main point of the article? I think we do understand a lot about the universe, even though there's also a huge amount we don't. I do think we understand "the basis" as Asimov put it -- it's just that even with the basis there's a lot we don't understand.
b_e_n_t_o_n 1y ago
Forgive me if this is a stupid interpretation and question, but are you basically saying that the tools we use to measure the universe actually produce our knowledge, rather than reflect an accurate model of reality? As in, in an alternative universe where we used different measurement tools, we would have discovered entirely different phenomena that we would consider to be part of the universe, but is really just a different way of interpreting the single substance of the universe? If so this is compelling to me. In the same way that or senses impact our view of what exists and how it exists, but it's really just an interpretation of what's out there.
- nathan_compton 1y ago
  I'd say its subtle. The instrumentalist just says that measurements are reality period and that there isn't anything to say about what goes on between measurements. You can sort of see this at an extreme in QBism. You just write down the quantum Bayes rule and that is all you commit to saying about the universe. I'd argue that what physics finds are (possibly non-unique) mathematical structures which correlate to the physical world. Because they are non-unique it is, in my opinion, silly to say things like "spacetime is a 4d manifold of Lorentzian signature with a connection like so and so, blah blah." There are other ways to describe the same dynamics which offer a different ontology and so we shouldn't just assume the terms in our physical models correspond to things in the universe. I think we reasonably can say "there exists a thing in the universe or a part of the universe that has the property that we can describe it with a 4d manifold of Lorentzian signature and so on." So physics does identify properties that hold for parts of the universe on certain time, length, action scales. But I think the general vibe of physics in the 20th and 21st centuries is that we don't know what those things are beyond the properties we give them. Maybe that is what knowing what something is is?

kitchi 1y ago

As another dude with a doctorate in Physics, I have to disagree with you (at least somewhat). > From this point of view as our ability to connect experiment with outcome has increased our ability to actually say what it is we are even talking about outside of the purely instrumental has decreased since the 19th Century. Back then we though we knew that there were atoms or electrons or whatever. Light waves or photons. Now, I would argue very strenuously, we genuinely have no understanding at all of what those things are outside of a set of purely instrumental definitions which leave a lot to be desired. I disagree with this entirely. The existence of QFT, and our knowledge of the inconsistency between say GR and the quantum realm does not negate the idea of photons and electrons as real, measurable quantities. The fact that we have GR does not negate the fact that we still use Newtonian gravity in regimes where it is sufficiently accurate. All the new knowledge we have learned still is (and absolutely must be) consistent with our old knowledge that has been proven correct in the regimes that they were proven correct. This is effectively what Asimov is saying (as I understand anyway) - the knowledge that the Earth is a sphere does not invalidate the assumption that the Earth is flat approximately and locally. I would also argue that the only things we can "know" are what you call the instrumental definitions. We only know what we measure. The rest is interpretation, and self-consistent understanding. String theory can tell me that we have several dimensions etc but until we have a way to measure and check it remains a conceptual framework to make predictions, rather than a description of how things really are. GR is much closer to a description. It told us about the precession of mercury, it told us to account for time dilation so we can use GPS satellites. It also predicted black holes, which were conceptually consistent but it's only been in the last ~ 5 years that we have the closest thing yet to experimental verification with the Event Horizon Telescope and gravitational wave measurements. If another theory comes along and explains all of GR with a different explanation for black holes, we will need still more accurate measurements to discriminate between the two theories. Knowledge is only as accurate as we can measure.

glenstein 1y ago
I agree much more with your approach. The way I've heard it best described is these notions of electrons and photons etc will still be retained as a special case of whatever theory supersedes them, which is critical, because that's at the heart of the "relativity of wrong" argument. Some take the prospect of a future revision of theories to mean our present state of knowledge is no different than any prior failed theory, which I think is an urgently, catastrophically wrong, catastrophically confused way to regard the history of scientific knowledge.
nathan_compton 1y ago
I don't think you get my point because I don't think of anything you are saying as having anything to do with what I was saying. If you have a purely instrumentalist view of reality, where, as I said, your so-called knowledge is actually just a model of an unknown thing which you employ to predict the measurements you read out against a ruler or on a meter or something, then yes, we've made progress exactly of the kind you describe. But I was trying to make a point about epistemology and ontology. Physics has actually been pretty catastrophic for ontology. I don't think its wrong to say that from the point of view of physics we simply do not know what anything actually is. > I would also argue that the only things we can "know" are what you call the instrumental definitions. We only know what we measure. The rest is interpretation, and self-consistent understanding. Yes. But this is a fairly radical position historically and philosophically. Most people would say that there is more to existence than measurement and I while I share your instrumentalist sympathies, like most physicists, I don't see the philosophical case that we can have a consistent worldview if we denounce all knowledge not related to measurement as a total non-starter. Think about what instrumentalism really means. When you utter the sentence the earth is an oblate spheroid, you are actually making an incredibly complicated set of statements about the outcomes of experiments. If we take the instrumentalist view the measurement doesn't actually tell us the earth is an oblate spheroid - it just tells us that if we make a series of measurements then they come out in such a way as to be concordant with a model of the earth as an oblate spheroid. Are you really prepared to give up the idea that the earth is a thing you can know about? I actually rather think physics strongly encourages us to adopt the instrumentalist view, primarily because it seems so clear that physics has a local character. In GR there simply is no state of affairs whatever about what is happening "right now" except at the point in spacetime where you make a measurement. Really think about what that means. If we are standing at the north pole and make a measurement of some kind, how can it pertain to the earth as a distributed object in space when we know GR says there is no state of affairs pertaining to that object at the moment of the measurement? GR tells us all about what the outcome of various measurements will be, but it also calls into question what precisely those measurements might mean. The instrumentalist is committed to the idea that the only thing we can talk about is the results of measurements. What the measurements operate on is just not something we can know. I think that's weird. Physicists often conflate their mathematical models with reality and that lets them think an instrumentalist view is sufficient: the measurements coming out such and such a way is taken as evidence that the universe is filled with objects consistent with the model. But that association is non-trivial in modern physics.

the_af 1y ago

Your answer here puzzles me. It seems as if you intended it to disagree with Asimov, while in practice you actually agree with him and disagree with the English Lit professor?

nathan_compton 1y ago
Yeah, I'm not disagreeing with Asimov at all, I just think his characterization of physics as constituting knowledge is overly enthusiastic. Like, yes, its clear physics constitutes knowledge of some sort, but I think its much less knowledge of what things actually are than Asimov might be prepared to entertain. The reason I raise the point is that its at least conceivable that we could have found ourselves in a world where physics discovered a fundamental ontology of the universe. Eg, maybe we could have discovered that quantum fields could be consistently described at all scales and thus we could more definitively say "yes, Virginia, the universe is composed of quantum fields." But we did not find this. Quantum Fields are widely understood to be effective descriptions of some unknown phenomenon which may not even resemble anything which makes intuitive sense with the rest of the way we think about physics. And all of that is to say nothing about quantum mechanics or quantum gravity. This isn't a trivial observation. We seemed to know more and more about the ontology of the world up to and perhaps slightly after the annus mirabilis. Simply establishing that atoms existed was a sort of ontological climax which then unraveled into a flaccid denouement as quantum mechanics and then QFT and the inability to formulate quantum gravity cast deep doubt on what things are even made of or whether its even possible to conceive of things at all. I stress again, this might not have happened. I can imagine some possible world where t'Hooft like cellular automata were somehow confirmed and the question of ontology was well and truly put to bed or at least for any but the most extreme philosophical skeptics.
- the_af 1y ago
  But aren't you essentially arguing that, indeed, there's wrong and there's wronger, and refuting the English professor who seemed to argue that "everyone is wrong but until shown this they are convinced they are right, therefore all knowledge is impossible"? (i.e. a slightly less new age version of "everything is relative!"). In other words, that Asimov is saying 2+2=5, while the English professor is saying "there's not difference between 5 and 'purple' as an answer!". In other words, don't you agree with main point of the article? I think we do understand a lot about the universe, even though there's also a huge amount we don't. I do think we understand "the basis" as Asimov put it -- it's just that even with the basis there's a lot we don't understand.

b_e_n_t_o_n 1y ago

Forgive me if this is a stupid interpretation and question, but are you basically saying that the tools we use to measure the universe actually produce our knowledge, rather than reflect an accurate model of reality? As in, in an alternative universe where we used different measurement tools, we would have discovered entirely different phenomena that we would consider to be part of the universe, but is really just a different way of interpreting the single substance of the universe? If so this is compelling to me. In the same way that or senses impact our view of what exists and how it exists, but it's really just an interpretation of what's out there.

nathan_compton 1y ago
I'd say its subtle. The instrumentalist just says that measurements are reality period and that there isn't anything to say about what goes on between measurements. You can sort of see this at an extreme in QBism. You just write down the quantum Bayes rule and that is all you commit to saying about the universe. I'd argue that what physics finds are (possibly non-unique) mathematical structures which correlate to the physical world. Because they are non-unique it is, in my opinion, silly to say things like "spacetime is a 4d manifold of Lorentzian signature with a connection like so and so, blah blah." There are other ways to describe the same dynamics which offer a different ontology and so we shouldn't just assume the terms in our physical models correspond to things in the universe. I think we reasonably can say "there exists a thing in the universe or a part of the universe that has the property that we can describe it with a 4d manifold of Lorentzian signature and so on." So physics does identify properties that hold for parts of the universe on certain time, length, action scales. But I think the general vibe of physics in the 20th and 21st centuries is that we don't know what those things are beyond the properties we give them. Maybe that is what knowing what something is is?