What is Philosophy of Science? | Episode 1611 | Closer To Truth

I love science because science accesses truths. To me, trained in science, it seems obvious that science is external, objective, and absolute. But some disagree, claiming that science is internal, subjective, and relative. Moreover, can science address all questions, or are there limits to science? What is science, anyway? Science itself, an idea, a process, a way of thinking? How to get at the essence of science, discern how science really works, how science should work. All this is called philosophy of science. But should science care about philosophy? Should science value philosophy? I'm Robert Lawrence Kuhn, and Closer to Truth is my journey to find out. I cannot make sense of the world of existence unless I feel confident I can know things that are true. Science gives me such confidence. But how can I have confidence in science? Unsurprisingly, philosophers claim that philosophy is how. That philosophy of science clarifies science, strengthens science, enriches science. Even if most scientists have no need for philosophy, the challenge is put forth, and I'm up for it. To investigate the philosophy of science, I speak with leading philosophers. I start in Cambridge, England, with a former editor of the journal Mind, Simon Blackburn. Simon, I love science, I love philosophy, but some of my scientific friends tell me the only purpose of a good philosopher is to keep all those other philosophers away from science. That's very good. I hadn't heard that before. So, let's start at first principles. Why philosophy of science? Well, as soon as you've got a science, you've got a description of the world in scientific terms, you've got an alleged explanation of some phenomenon which a scientist gives you, you're going to start worrying about the terms of the explanation and whether it really is an explanation. Let's take, for example, Newton's theory of gravitation. When Newton published that in 1690, quite a lot of other scientists were disappointed, funnily enough. They wanted to know what gravity was. And Newton, apparently, didn't tell them what it was. He just told them what it did. So, what is the gravitational field? Now, of course, that may have been a scientific question which remained unanswered at least till the 20th and possibly the 21st century. But it was a question about how much the explanation had achieved and what was left to be achieved. And Hume came along, the philosopher, did some philosophy of science, and said that actually the kind of thing Newton did was the only kind of thing the human mind could ever do. So, that was a claim about the scope and limits of science. And that's a claim which needs evaluating. It needs looking at in its own right. This is very important, the scope and limits of science. Sure, yeah. And so, how can we descend deeper into that? I think it's probably good to go back to the 17th century before Newton. There was a rationalist ideal. The ideal was that if only we could see the world properly, we'd see why things must be as they are. Just as we think that two plus two must be four. That's straightforward. So, we'd see that gravity must work in the way it does. That rationalist ideal took a knock from Newton because Newton just said, this is how it is. Why it must be like this, that's up to God, we don't know. And that's what Hume said was the limit. We'd never managed to achieve the rationalist ideal. We'd never see why things must be how they actually turn out to be. So, science was always going to be empirical. It was never going to be a priori, as the jargon is. That is, something you could just excogitate. That argument is still in play today. Oh, yes, very much so. People would love a kind of theory of everything. It's often promoted as an ideal. Now, if Hume's right, you can't have a theory of everything because your theory will eventually have to depend on unargued premises, unargued starting points, bare happenstance. It won't be like mathematics. Hmm. Simon presents a strong empirical view of science. Science can describe what things happen, but cannot explain what things are. It's like a kind of universal limit, like the speed of light. The human mind can find regularities in nature, but not penetrate the foundations of reality. But most scientists do not bother themselves with philosophy, and some openly dismiss it as irrelevant, if not obstructive. I've found a fondness for putting to philosophers these dismissive attitudes of scientists. It's a good conversation starter. More important, it probes philosophy of science. Historically, hasn't philosophy prepared the way for science? An Oxford professor of metaphysics thinks so. I meet John Horthorn. John, some of my scientist friends would say philosophers have a great value in the world, and that is when they keep other philosophers away from bothering scientists. What do you say? One thing that they should remember is that philosophers historically have had a huge role in the development of science. In fact, it's only a recent thing that people clearly self-identified as philosophers rather than scientists, or scientists rather than philosophers. Aristotle, Descartes, Leibniz, Newton, and many others recognizably did stuff that was both science and philosophy, and there was no clear divide between them. So I think it's a very strange thought to be having that philosophy is useless, because there's no sharp divide historically between philosophy and science anyway. And the argument back is that you're certainly right historically, but now we've grown up, and now science is real, and that's the part of this past tradition that is maintained, and the part that was useless should be ejected. It's clear that philosophy as a discipline is the end of inquiry that isn't to do with, say, hands-on experimentation. There's a lot of science that is quite distant from hands-on experimentation, too, and what you find is that there's fairly seamless interaction between philosophers and scientists at that end of things. So if you look at foundations of physics, there's quite healthy collaborations going on between philosophers and cosmologists. They have particular skills in clarifying things, connecting disparate areas, looking at the logic behind certain argumentation, bringing a bit of discipline to what can be sometimes wild speculation, trying to do a little policing in terms of standards for theory choice and so on. And there's just no basis at all for sort of the kind of dismissive attitudes that you're describing. What are some of the contributions that philosophy can make to modern science? I mean, there are lots of issues of clarification in... I mean, I've been picking on the example of foundations of physics, issues about the interpretation of quantum mechanics. You know, there's been these proliferation of approaches among physics that physicists fighting with each other about how to interpret the foundations of quantum mechanics, whether Bohmians, Copenhagen, and so on. And all the evidence is that philosophers have been actually quite adept at clarifying what's at stake, looking at, in a careful way, at what the evidence is and what sorts of standards for theory choice are in play and available and so on. So there's a good example of something that's one of the deepest, you know, a range of very deep questions about the ultimate structure of the physical universe where there's no reason to think that philosophers aren't currently playing a very important role and will continue to do so. Obviously, there are certain areas of science where the structure of the theories is pretty clear, the standards for success are pretty clear, where philosophers aren't going to play a good role. I mean, philosophers aren't going to help people cook nice dinners either, you know? So it's not like philosophy helps everywhere. I don't want to say that, but philosophers do have a special ability to help in areas where there's need for clarification, both of the nature of the theory and the evidential standards that are being brought to bear. John argues that philosophy benefits science by clarifying ways of thinking, how issues are described, how evidence is considered, how theories are constructed. But how does all this wonderful stuff happen? How does philosophy work its putative magic? I hear that several of my favorite philosophers are attending a conference on consciousness, so I go to Tucson, Arizona, to see how they react when some scientists attack most philosophers. I meet a philosopher of mind who stresses philosophy's impact on the world, Rebecca Neuberger-Goldstein. Rebecca, it seems that many scientists today have taken a special interest in attacking philosophy as not only worthless, but debilitating to doing good science under the theory that philosophy was and is pre-scientific. It was fine when we didn't have science, but now that we do have science, it gets in the way. Yes, and there's a lot in the history of science and the history of philosophy to support that view, if you look at it very superficially, I would say. Of course, all science began as philosophy. The word science didn't even come into existence until the 19th century. It was called natural philosophy, and that covered physics, and it covered cosmology. And as science makes progress, the sphere of philosophy shrinks. There's no doubt about that. So the questions that had been philosophical sometimes are proto-scientific questions, and it's simply a matter of science to develop the techniques, the methodology, so that it can turn them into empirical questions and then make progress. So that's generally the argument, and the terminus of this ongoing problem is that the set of philosophical problems will go to the null set. Well, here's why that won't work, I would say. First of all, you need quite sophisticated philosophy to make that argument. You need a way of demarcating science, for example, from other explanations. Who is the person to whom all scientists turn when they want to make that demarcation between a scientific theory and a non-scientific theory? Karl Popper, right? Falsifiability. Who was Karl Popper? He was a philosopher, and he made the argument philosophically. So, you know, to help yourself to philosophical conclusions in order to argue that, you know, philosophy is not necessary is just, it's not kosher. The other thing, of course, is, you know, to say that science is discovering the nature of reality, and, you know, we don't need philosophy, once again, to make the claim for scientific realism depends on very, very sophisticated work that has to be done in philosophy of science. Because the scientific method, per se, by definition, deals with and is assuming naturalism, methodological naturalism, ontological naturalism, that that's the only reality is the natural world. You have to argue for that, too. Two separate issues. One is the actual substance of the world, ontology, and the other is the methodological approach. There are many scientists who are not realists about the physical, the external world, the physical world. The problems of quantum mechanics have produced so many interesting points of view, and one of them is as idealism. I mean, things don't exist until we observe them. This kind of question, what is the consequence of a particular theory? We know the theory works. It gives us predictions that have not yet been falsified. But how do we make sense of the whole thing? What view of reality does it lead to? You're in the domain of philosophy then. Most of the people I know who argue for this kind of, the eliminative view of philosophy, that science is discovering the nature of reality, there is going to be no place for philosophy, first of all, don't understand that philosophy does other things than trying to describe reality. I do believe that is the sphere of science. Science is this wonderful technique that we've worked out that acknowledges how wrong we get everything and gives reality a chance to answer us back when we're getting it wrong. And I think that's what we have to depend on in order to understand reality. Philosophy has other uses. For example, what I just said, that was pure philosophy, right? Science can't give you that interpretation of science. That was philosophy. So, that's my answer. Rebecca offers a robust defense of philosophy. Science cannot escape philosophy's power, she argues, and shouldn't seek to, because philosophy makes science make sense. But to most philosophers, facilitating the theory and practice of science, while useful, hardly represents the deep value of philosophy. What is the deep value of philosophy? I ask a philosopher of mind, language, and social construction, John Searle. John, there are some scientists who say that philosophy is pre-scientific. General public might think that philosophy is ivory tower-ish. What's the value of philosophy in the modern world? Yeah, well, a lot of it depends on what you think is valuable. To me, these questions are absolutely fascinating. I cannot imagine living a life without being obsessed by philosophical questions. I've always been obsessed by these questions since I was a small child. What are your favorites? Well, my favorites is how does the mind represent reality? How does language express the mind? How is a society formed and maintained? And above all, what's the nature of the real world, and how do we have access to the real world? That's a start, and I can't imagine somebody not being interested in those questions. But I wouldn't want to give you the idea that the value of philosophy depends on whether or not it's got some practical use in the marketplace, because the value of philosophy is like the value of anything that's valuable in itself. It's absolutely fascinating, and it makes life worthwhile, really. Nonetheless, there are a lot of practical importance to philosophical investigations, and in particular, as a general critique of society and intellectual life. So, for example, here's an interesting philosophical question. The social sciences proceeded essentially by imitating the natural sciences. To some extent, that was successful, but in most cases, it really wasn't very successful. Now, that raised an interesting philosophical question. How is the subject matter of the social sciences different from the natural sciences, and how is it different in ways that would render the model provided by the natural sciences inappropriate for the social sciences? But another point I would want to make is, at the level at which I work, I don't make a distinction between philosophy and science. So, a narrow scientific question is, what causes cancer, let's say? A philosophical question is, what's the nature of causation? And of course, that question is in part addressed by thinking how causes work in the sciences. So, we have had to alter our conception of causation by discoveries in physics. There's a constant interplay between philosophy and science, and indeed, the very greatest scientists, like Einstein or Newton, are philosophers, and both of them thought of themselves as philosophers. But some scientists say that just that kind of question, what is causation? Science has usurped philosophy, and philosophy was doing all sorts of things that really weren't addressing the question coming up with dead ends and paradoxes, and science is just getting down to the facts and how it works, and now they know causes, and some are Newtonian, and some are quantum mechanical, and now we know. Yeah, but the problem is that they don't make it look as if all of this is already established, or this discussion is still going on. Einstein, he could never accept quantum indeterminacy. He thought that cannot be the last... And that's a philosophical objection. That's a philosophical objection. Now, the fact is, we've had over 50 years of experiments, and they always support quantum mechanics, in this particular quantum indeterminacy. There are certain sorts of experimental procedures which are more or less cut and dried. You perform the experiment, and it comes out, or it doesn't, but at the level that I find interesting, where you're asking yourself, well, what is the significance of all of this, and how much do these methods apply elsewhere, and what's the logical form of the explanation provided by this type of investigation? I think those are essentially questions where there's an overlap, where you can't make a sharp distinction between philosophy and science. There are a lot of the questions that interest me most, though, that most scientists can't see are real questions, like how does language relate to reality? They think, well, that must be some atomic explanation of that. Or, what's the ontology of society? So, when you deal with the ontology of society, is that a purely theoretical, or can that actually help understand the fundamental being of what it is? Yeah, I think if you want to understand anything, you better understand the ontology. You better understand the nature of the phenomena that you are describing. Now, I have to tell you, most social scientists don't worry about that. I mean, I know a guy who's doing studies of trade unions, the decline of trade union membership. It's a straightforward sociological problem. But what exactly is a trade union, and how does it relate to other institutional structures, and how do these institutional structures come into being, and how do they continue to exist? Those, to me, are the fascinating philosophical questions. And if I were... And should that inform his study? I think it should. Or will it confuse him? No, well, who knows? That's always a possibility. But I think you're bound to do better work if you have a deeper philosophical grip on the material. Now, of course, life is short. And if a guy wants to devote his life to just studying decline in trade union membership and not worry about all these philosophical problems, that's okay. It's a free country. But my own view is you get much greater philosophical depth, much greater intellectual depth, if you understand the ontology, if you understand the theoretical underpinnings of what it is you are investigating. To John, the profound value of philosophy is posing fundamental questions. Philosophy is the best way, perhaps the only way, he says, for finding the foundations of things. But if so, why then do so many scientists dismiss or ignore philosophy? I love probing this point, and I do so with a no-nonsense philosopher, known for exposing woolly thinking and expanding hardcore science, Daniel Dennett. Dan, philosophy is under attack. One prominent scientist told me that there is value in good philosophers, but that only value is to keep the bad philosophers off my back. I have some sympathy for that view, because it seems to me that I spend a lot of my time doing pretty much the hat or trying to. So, scientists would think you're a good philosopher because you keep all the bad ones from annoying too many scientists. But if none of you existed at all, so much the better. Well, I think there's a good positive role for philosophers. What philosophers are good at is clarifying questions. At their best, that's what they're good at. And in any area where you're not quite sure what the right questions are, whether you're asking the right questions, that's where what you're doing is philosophy, whether you like it or not. And the reason that a trained philosopher can help with that is that we know the history of all the tempting bad answers. It is really fascinating and even entertaining to watch really brilliant scientists start thinking about tough issues and reinventing all the mistakes of the history of philosophy. Why are they reinventing them? Because these are very tempting mistakes. And if you don't know the history of what's wrong with Hume and Kant and Aristotle and Plato and all the rest, then you're going to fall into those mistakes, burn their fingers a few times like that, and then they begin to realize that there is a role for philosophy because they don't know for sure if they're asking the right questions. What's an example of that? Let's look at consciousness. So many people, when they start thinking about consciousness, are basically thinking, as I like to say, about the show that's going on in people's heads and how you account for that. But that's... They get off on the wrong foot if they think it's obvious that that's what's going on. It takes some heavy lifting, philosophical lifting, to show them that there are alternative questions which really get at what they're interested in, which don't presuppose that there's a place where the show goes on. And if you think there's a place where the show goes on, then you're postponing the serious work. You're only doing half the job. Sometimes I ask people in this position, I say, what's the product of apple trees? And they say apples. I say, no, apple trees are the product of apple trees. Apples are an intermediate product. Consciousness is an... It's not the end of the line. It's an intermediate product. And the ultimate product is intelligent, apt, guided behavior, sensitively guided behavior in the world. Until you answer that part of the issue, until your theory handles how the experiences are consumed, how they're used, how they modulate your behavior, you don't have a theory of consciousness. So, about half the people in the field simply stop short. They don't even try to do anything but the first half of a theory of consciousness. And that's a mistake. And it's a philosophical mistake. Yes, philosophy is a progenitor of science. But we do not worship our ancestors, and so that history, to me, has marginal meaning. I want to know today, should science value philosophy? Sure, but only if philosophy benefits science. Here are five possible benefits. One, philosophy clarifies the kinds of questions science asks, enabling answers that are more precise. Two, philosophy expands the kinds of questions science can ask, enlarging the scope of problems that science can solve. Three, philosophy enhances experimental design and the robustness of evidence, strengthening the scientific method. Four, philosophy defines the boundaries between science and pseudoscience, marking certain fields or claims as unscientific. Five, philosophy sets the limits of science, distinguishing science from non-science. Take the relationship between science and morality, or between science and art. With neuroscience blurring boundaries, careful philosophical analysis is vital. Though science is king, philosophy can steady the crown, keeping science closer to truth. For complete interviews and for further information, please visit closertotruth.com.