instrumentalism vs realism
I'm attending an event called Freezing Woman this March, and as part of it I'm planning on putting together some kind of interesting "microtalk". At first, I was thinking this would be similar to talks I've given at Burning Man, which have ranged from 30-60 minutes plus Q&A. But apparently it's supposed to just be 5 minutes. I was a little disappointed with the time limitation, but I still get excited any time I'm allowed to give a completely open-ended talk on anything in the world I find interesting! How awesome is that? Time to share some knowledge.
So for the past couple weeks I've been brainstorming about different ideas and topics I might want to cover. I realized that there is a huge connected set of issues that I'm maximally interested in, but they span so many different related topics that there's no way I could even fit them all into an hour talk. So I'll have to significantly narrow it down. All of them are in some way related to either philosophy of science, philosophy of quantum mechanics, philosophy of mind, philosophy of mathematics, or epistemology. It's kind of the intersection of all of them that interests me, but I've been having trouble isolating one without feeling like the others are too crucial for understanding any of them.
Since physics is the area where most of my expertise lies, my initial thought was that I wanted to give an overview of the main philosophical lessons one learns in the course of learning more and more about the physical structure of the world. A lot of naive common sense notions are replaced by other notions, and you're whole picture of reality starts to become a bit different. Over time you start to even forget how most people think about the world. My first thought about what a good title for the talk would be, was "materialism". It could basically be me summing up what the ancient view of materialism was, and summing up how that view has changed over the course of the history of physics, and finishing with the current status of materialism. Which in some ways stands in a very ironic state: on the one hand, the evidential support for some very minimal kind of physicalism/naturalism has grown extremely strong, but on the other hand the physical structure of the world as uncovered by scientific investigation has turned out to be so much more weird and different than was envisioned by the original "materialists" that it seems like that's the wrong word for it and now conveys something pretty different from what was original meant by it or from what an ordinary person unfamiliar with any of this stuff might imagine by it. In some ways, it's clear that the original doctrine of materialism was completely wrong, but compared to any of the early theories that predated it or were seen as valid alternatives to it (idealism, dualism) it still seems like the closest to the truth. But who knows? My views on this have evolved within the past few years, and I might be willing to admit now that some aspects of idealism or dualism might need to be reincorporated into it. Or, maybe neutral monism or something like "mathematicism" is a better term than materialism.
But when I started exploring the main issues, and reading up on this again, I realized that the debate over physicalism/materialism is not really at the heart of what I wanted to cover. What I'm really more interested in is the debate between instrumentalism and scientific realism. The modern debate over materialism (which has by now mostly been renamed physicalism since it's been obvious from physics for a long time that most of the world is not "material" in any real sense--matter is just one form of energy/information and a lot of the world isn't in the form of matter at all) is within the province of philosophy of mind. The realism vs instrumentalism debate is instead within the province of philosophy of science and its most up to date form is within philosophy of quantum mechanics, where it takes shape in the debate between the Copenhagen Interpretation and the Many Worlds Interpretation.
The modern physicalism debate centers on whether consciousness can be reduced to--or eliminated in favor of--physical brain states. This is something I have my own opinions on, but which I'm far from an expert on. Whereas the debate between the scientific realists and instrumentalists is closer to my expertise since it's a debate about whether the theoretical constructs which physicists come up with (particles, fields, strings, branes, the quantum wavefunction, etc.) can be said to be "real" in any sense or if they are simply convenient fictions used to aid us in the practical business of predicting the outcomes of future experiments. Phrased in another way, the debate is over whether science has anything to say about what the world "is", like what it is ultimately made of, or if instead it only gives us a useful oracle for predicting future experiences. An instrumentalist would say that science cannot tell us about what the world beyond our senses "is", and a hardline instrumentalist might even argue that there is no fact of the matter at all about what the world is, that any such questions are just meaningless "metaphysical" nonsense.
I've always been a bit more on the side of scientific realism in this debate, however I acknowledge that there are many valid points on the instrumentalist side. In fact, I think the real answer is somewhere between pure realism and pure instrumentalism; the most accurate view of what science is and what it can say, I believe, must incorporate some aspects of both.
The most extreme form of instrumentalism was logical positivism. Actually I'm still unclear on this but it seems to me that instrumentalism and positivism mean almost the same thing and their histories are very intertwined. It seems like instrumentalism began with a French physicist / philosopher of science named Pierre Duhem from the late 19th century. In the early 20th century, it became more extreme and kind of morphed into logical positivism, where Niels Bohr and other founders of quantum physics used logical positivism to interpret quantum mechanics and came up with the Copenhagen Interpretation. Niels Bohr was both an instrumentalist and a logical positivist. So was Werner Heisenberg, although he read and wrote less about philosophy than Bohr did. Later, Quine revived instrumentalism. And pragmatism also became intertwined with instrumentalism. It's kind of ironic that the modern revival of instrumentalism was mostly Quine's doing, considering I don't think of myself as an instrumentalist, but Quine is probably my biggest hero in philosophy--mostly because of his explanation of why there is no meaningful distinction between analytic and synthetic truths.
Today in physics, the Copenhagen Interpretation of quantum mechanics, and instrumentalism in general, remains the dominant ideology. But in philosophy, as I understand it, logical positivism has been completely discredited and realism has made a comeback, while instrumentalism in a milder form remains acceptable to many philosophers but is probably overall less popular than realism (although I'm unsure of this last part and would love to find out what exactly the breakdown is).
My own belief? Either some very mild form of instrumentalism is right or some mild form of realism, or some combination. Surely the extreme forms of instrumentalism are wrong. Actually, I tend to suspect that the truth is somewhat more toward instrumentalism than philosophers realize, but somewhat more toward realism than most physicists realize. Although it is quite interesting that the physicists, you would think, would if anything have a bias toward thinking that what they do does in some way say something meaningful about the world--but instead it tends to be the opposite. Maybe by putting it in that way I'm making a straw man out of instrumentalism though?
To be continued...
So for the past couple weeks I've been brainstorming about different ideas and topics I might want to cover. I realized that there is a huge connected set of issues that I'm maximally interested in, but they span so many different related topics that there's no way I could even fit them all into an hour talk. So I'll have to significantly narrow it down. All of them are in some way related to either philosophy of science, philosophy of quantum mechanics, philosophy of mind, philosophy of mathematics, or epistemology. It's kind of the intersection of all of them that interests me, but I've been having trouble isolating one without feeling like the others are too crucial for understanding any of them.
Since physics is the area where most of my expertise lies, my initial thought was that I wanted to give an overview of the main philosophical lessons one learns in the course of learning more and more about the physical structure of the world. A lot of naive common sense notions are replaced by other notions, and you're whole picture of reality starts to become a bit different. Over time you start to even forget how most people think about the world. My first thought about what a good title for the talk would be, was "materialism". It could basically be me summing up what the ancient view of materialism was, and summing up how that view has changed over the course of the history of physics, and finishing with the current status of materialism. Which in some ways stands in a very ironic state: on the one hand, the evidential support for some very minimal kind of physicalism/naturalism has grown extremely strong, but on the other hand the physical structure of the world as uncovered by scientific investigation has turned out to be so much more weird and different than was envisioned by the original "materialists" that it seems like that's the wrong word for it and now conveys something pretty different from what was original meant by it or from what an ordinary person unfamiliar with any of this stuff might imagine by it. In some ways, it's clear that the original doctrine of materialism was completely wrong, but compared to any of the early theories that predated it or were seen as valid alternatives to it (idealism, dualism) it still seems like the closest to the truth. But who knows? My views on this have evolved within the past few years, and I might be willing to admit now that some aspects of idealism or dualism might need to be reincorporated into it. Or, maybe neutral monism or something like "mathematicism" is a better term than materialism.
But when I started exploring the main issues, and reading up on this again, I realized that the debate over physicalism/materialism is not really at the heart of what I wanted to cover. What I'm really more interested in is the debate between instrumentalism and scientific realism. The modern debate over materialism (which has by now mostly been renamed physicalism since it's been obvious from physics for a long time that most of the world is not "material" in any real sense--matter is just one form of energy/information and a lot of the world isn't in the form of matter at all) is within the province of philosophy of mind. The realism vs instrumentalism debate is instead within the province of philosophy of science and its most up to date form is within philosophy of quantum mechanics, where it takes shape in the debate between the Copenhagen Interpretation and the Many Worlds Interpretation.
The modern physicalism debate centers on whether consciousness can be reduced to--or eliminated in favor of--physical brain states. This is something I have my own opinions on, but which I'm far from an expert on. Whereas the debate between the scientific realists and instrumentalists is closer to my expertise since it's a debate about whether the theoretical constructs which physicists come up with (particles, fields, strings, branes, the quantum wavefunction, etc.) can be said to be "real" in any sense or if they are simply convenient fictions used to aid us in the practical business of predicting the outcomes of future experiments. Phrased in another way, the debate is over whether science has anything to say about what the world "is", like what it is ultimately made of, or if instead it only gives us a useful oracle for predicting future experiences. An instrumentalist would say that science cannot tell us about what the world beyond our senses "is", and a hardline instrumentalist might even argue that there is no fact of the matter at all about what the world is, that any such questions are just meaningless "metaphysical" nonsense.
I've always been a bit more on the side of scientific realism in this debate, however I acknowledge that there are many valid points on the instrumentalist side. In fact, I think the real answer is somewhere between pure realism and pure instrumentalism; the most accurate view of what science is and what it can say, I believe, must incorporate some aspects of both.
The most extreme form of instrumentalism was logical positivism. Actually I'm still unclear on this but it seems to me that instrumentalism and positivism mean almost the same thing and their histories are very intertwined. It seems like instrumentalism began with a French physicist / philosopher of science named Pierre Duhem from the late 19th century. In the early 20th century, it became more extreme and kind of morphed into logical positivism, where Niels Bohr and other founders of quantum physics used logical positivism to interpret quantum mechanics and came up with the Copenhagen Interpretation. Niels Bohr was both an instrumentalist and a logical positivist. So was Werner Heisenberg, although he read and wrote less about philosophy than Bohr did. Later, Quine revived instrumentalism. And pragmatism also became intertwined with instrumentalism. It's kind of ironic that the modern revival of instrumentalism was mostly Quine's doing, considering I don't think of myself as an instrumentalist, but Quine is probably my biggest hero in philosophy--mostly because of his explanation of why there is no meaningful distinction between analytic and synthetic truths.
Today in physics, the Copenhagen Interpretation of quantum mechanics, and instrumentalism in general, remains the dominant ideology. But in philosophy, as I understand it, logical positivism has been completely discredited and realism has made a comeback, while instrumentalism in a milder form remains acceptable to many philosophers but is probably overall less popular than realism (although I'm unsure of this last part and would love to find out what exactly the breakdown is).
My own belief? Either some very mild form of instrumentalism is right or some mild form of realism, or some combination. Surely the extreme forms of instrumentalism are wrong. Actually, I tend to suspect that the truth is somewhat more toward instrumentalism than philosophers realize, but somewhat more toward realism than most physicists realize. Although it is quite interesting that the physicists, you would think, would if anything have a bias toward thinking that what they do does in some way say something meaningful about the world--but instead it tends to be the opposite. Maybe by putting it in that way I'm making a straw man out of instrumentalism though?
To be continued...