Welcome to Stuff to Blow your Mind from how stop works dot com. Hey, you're welcome to stuff to Blow your Mind. My name is Robert Lamb and I'm Joe McCormick and Robert I want to put you in a scenario. All right, let's do it. Okay, So just recently I was at a family gathering, a wedding and old family event. And when you go to a you know, family reunion type event, you meet a lot of people you haven't seen in a long time. You get to catch up on what they're doing. So imagine you are at a family reunion type event and you're talking to a distant cousin of yours who's going to night school to get her graduate degree. And you're like, oh, cool, yeah, I do I do a science show. What what are you studying at your your school? And she can give you a couple of answers. Let's contemplate the first one. The first answer is, oh, I study radio astronomy. So we look at distant objects in the sky by measuring the radio frequency energy they admit. And you're like, cool, so how does that work? And she says, well, so we aim radio telescope arrays at far away stars and galaxies, and we collect the data and feeded into computers, and that allows us to draw conclusions about the physical properties of those objects. Sounds legit. Okay, here's another answer she could give. She says, Oh, yeah, I study psychic astro sociology, So we study distant civilizations in the Milky Way galaxy by tuning into the psychic energies that they beam to our planet through their Numa transmitters. The number of red flags already, yeah, So you don't even really have to be a scientist or even very scientifically literate to tell that one of these answers refers to real science and the other one does not. But the question you should ask yourself is what is the criterion you have used. You've intuitively used some kind of rule to rule in one of those answers as real science and rule out the other one as fake side and pseudoscience. It sounds like garbage. So you know the difference when you see it, But what is the principle that actually makes the difference right? And and this question becomes ever more important when you when you move away from the obvious examples and you get into that h that stretch of gray area that that that borders the dividing line. Um. Now, in terms of pseudoscience, I do want to throw in real quick that the oldest known use of the word pseudoscience dates back from when the historian James Petite Andrew referred to alchemy as quote a fantastical pseudoscience. And certainly, un you can make that the case for that with alchemy. Well maybe if you have a closed mine, I'm gonna get some gold eventually. I mean, in some ways alchemy was kind of a protoscience, but the the actual scientific properties in alchemy, and this is kind of a topic for another day, um are kind of lost amid all the the cult concerns. But in the philosophy of science, exactly this problem, this problem of what rule do you use to tell the difference between science and pseudoscience has a name. It's a named problem, right, Yeah, the demarcation problem. Yeah, drawing the boundary, setting the border between one side and the other, between truth and falsehood, between good and bad, between sin and virtue. I mean it and it sounds pretty simple, but it's a it's a very important concern for the philosophy of science. For a couple of different reasons. From a purely theoretical point of view, uh, it's important philosophers talking to each other about what things mean and the depth of their meaning. But also from a very practical point and it's because obviously, science is humanity's most reliable font of knowledge. It's the tower we've built that we use to ascend to new heights. Uh, technologically speaking, cosmologically speaking, it's our it's our best method for advancing solutions, and something we're constantly touting in advertising, healthcare, criminal justice, environmental policy, entertainment, politics, and everything in between. So science is applied to science, isn't just uh, intellectual endeavor taking place in a vacuum. Once we have a scientific conclusion, we very often take that conclusion out and do something with it. Yeah, it's not just in the monastery on the hill. It's down in the marketplace, it's in the household. It's it's factoring in your decisions. I mean, like we're saying earlier, it's one thing to to hear someone's diet tribe about some very fringe e topic and and instantly judge, oh, well, that's that's complete malarchy. That's studioscience. But where it gets gets weirder is when you're picking up a product at the at the supermarket, you know, or you're you're you're the vitamin supplement exactly hand, and then you start trying to figure out, Wait, this is speaking the language of science. It's not hitting those crazy keywords that my cousin knows throwing out at this imagined wedding. What am I to do? Mega vitea fan burns fat fast. Should I trust this? I mean? Yeah? So it has real implications in the real world that it impacts your wallet, and it impacts the budgets of countries that fund scientific research. You don't want the government funding research in something that is complete bunk. So getting to this question of demarcation, like how do you tell the difference? What rule do you use? One one common dictionary definition of pseudoscience is something like quote a collection of beliefs or practices mistakenly regarded as being based on the scientific method. Well that's not very helpful, is it right, because that that just it's circular. It invokes the concept of science to say what's not science? So it's not helpful for solving the demarcation problem because it just says pseudoscience is that which appears to be science but is not those who are entering the tower of science and not doing science there, or something to that effect, because yeah, because the uh, the the scientific method is still present, at least it's invoked, right, So it becomes difficult to decipher. Yeah, So to really solve the problem, you'd want to come up with some descriptive rule that exclusively describes science. It's like a descriptive statement that describes everything that is science and rules out everything that is not science. But it's hard to come up with a rule like that, isn't it. Yeah. I mean again, especially as you you become closer and closer to the boundary line. You know, it's um because it we'll discuss here. It's it's kind of like imagine the border between two states and you have you have a couple, you have a couple of towns, right, and ones just immediately on one side of the state line, the others on the other. And if you're applying of it's a very strict understanding of boundary lines here, then this one is definitely in Arkansas, and this one's definitely in Tennessee. But then if you start saying, well, actually, there's a little room, uh to to go on either side. Then it just then you're confounded, All right, is this one in Tennessee or is this one in Arkansas? How about this one? Are they both in both states? Or is it just how I feel when I visit that town? Right? So, a lot of the solutions to the demarcation problem try to draw some clear line. Okay, here we have an exclusive rule that makes the distinction. So I know a lot of scientists and some philosophers of science would probably want to make a distinction based on empiricism as as the first criteria here. Right. So, empiricism is the idea that it involves observations. You know, it's what you see or what you can measure externally. That science can't be just an internal logical exercise that has no contact with something you see happening in the real world. Yeah, there has to. It has it's evidence based. Right. Then. Of course you've also got the you know, the scientific method that you learned in elementary school. Some people would look at that and say, okay, you know, that's basically how science works. You ask a question, you make an educated guess, that's your hypothesis. You do some kind of empirical test on observable reality to see if your guess is correct. Then you analyze the results and draw conclusions, and you know, that's a good simplified version for kids to learn. Yeah, I mean, how do you walk into a dark room and find out what the what what the room contains and accurately judge it without you know, hitting your head on something. But there's a problem with that if we're trying to describe science as it happens in the real world of professional discoveries, because it doesn't. That method doesn't very closely describe the process by which we came up with all kinds of important and correct scientific theories in history, Like lots of theories in physics, for example, we're just conceived simply as abstract thought experiments, and they went for a long time without empirical testing. Now we've empirically tested them and we know. But they just started in Einstein's head. There are a number of scientific concept that were conceived or certainly that the the people behind them attributed their conception to dreams, you know. So it's hard to fit the dream world into any serious contemplation of scientific method, right. Yeah, So there are plenty of examples you can go through through history of scientific theories that we didn't have empirical confirmation of for a long time, even after people had accepted them as probably true. You know, one good example that it comes up in the debate we're gonna be talking about today is the question of atoms. For a long time, scientists knew that matter was based on atoms, but there was no test they could do to confirm the existence of atoms. Now there are, fortunately, but we didn't. We didn't have those tests for a long time. Another problem with the basic scientific method you learn an elementary school is that if you just have some bad methodology, you can rule in plenty of pseudoscience. Right Like, if you just use the scientific method, but you use it poorly, you can prove the existence of psychics, ghosts, aliens, whatever you want. Yeah, I mean we see this time and time again. Right, There'll be one guy who is able to create a zero gravity state in a lab, and then any and everyone else tries to replicate it, and they don't get the same results. And therefore either either what everybody's wrong, and this one guy got it right once. No, it's the reverse. Yeah, he used the method. He just did a really bad job of using the method. Another way that I think some people would address how to define science and uh and solve the demarcation problem is I think totally useless. And they define science in a kind of post talk back engineered pragmatic sense, as in, they define sciences the method of inquiry which produces correct and useful results. This is obviously not a helpful solution to demarcation problem. Now, if you're hearing all of this and thinking, yeah, but then again, I mean, scientists are just doing their scientific work. Do they really need to worry about all of this, Uh, this philosophical back and forth, Like, is this just a lot of talk that doesn't really amount to anything? I would argue, No, it is not. I think these philosophical concepts are crucial to to doing good science. Yeah, and uh, especially when you when you start facing the realization that you can't just do the science right. Uh. There's a there's a wonderful quote from Daniel Dennett from his book Darwin's Dangerous Idea, which we've discussed this in a previous episode, but he says, quote, scientists sometimes deceive themselves into thinking that philosophical ideas are only at best decorations or parasitic commentaries on the hard, objective triumphs of science, and that they themselves are immune to the confusions that philosophers devote their lives to dissolving. But there is no such thing as philosophy free science. There is only science whose philosophical baggage is taken on board without examination. I entirely agree with that quote. I think that's right on the money. I mean, if you hear a scientist say, I don't bother with philosophy. I'm not interested in philosophical content concepts. I just do the science. It's kind of like if you had a person running for president who says, look, I'm not political, I'm just gonna govern. Would you trust that person? I mean, the reality is what they are going to be governed by some kind of philosophy, whether they acknowledge it or not. And uh in the person who claims not to have a philosophy or not to have you know, any kind of ideology guiding them is just advertising the fact that they haven't thought very deeply about this. Yeah, they because I like the idea of a non political uh individual just judging without and just ruling without any kind of uh you know, weird hang ups and constraints and agenda. But for that to really work, you'd have to have like a superhuman you have to have someone with like a self moving soul. Was someone who could who could think and approach the task at hand with just pure logic, unmoved by the undercurrents of opinion, bias, trauma or longing. Uh. You know. Part of the the the issue here is that science itself, with the scientific method as its backbone, it's it's kind of a perfect engine, right uh and and we are it's flawed operators. So for perhaps you know what we need here, I would look at like the done universe, we need like Mentat scientists, um or we would need Dounyane scientists or bodhisattvas of scientific inquiry. What do you mean, Duniane? What is that? Oh? They're a there are people that are kind of like Mentats and m are Scott Baker's Second Apocalypse saga. So they've been able to just really through just generations and generations of selective breeding and uh and and personal training, they've managed to enter the two to breed a people that are completely uh, in the now completely in control all of their of their soul and their mind states. So they're they're not governed by uh, you know, past concerns, and when they encounter people that are not doniating, they can just completely manipulate them because they sort of stand outside of that path. Humans engineered to no longer have preferences to only be computers sort of yeah, yeah, pretty much. And but that's the other thing. Maybe what we need is an advanced hyper computer, some sort of you know, super AI. They could do all of the science that could that could be science without the human concerns. But we don't have that right now. We just have the humans with some help from the computers. Right. So today, the main topic that we're going to be talking about is the idea of empiricism and falsifiability in science. And we're gonna get to what those what falsifiability means in a second, but also about whether we have entered a phase in science where there is room for a concept to known as post empiricism. And if that sounds crazy to you, we will explain what the arguments are in just a bit. But we should bring it back to the history of this demarcation problem. How do you separate the science from the pseudoscience? And one of the most common answers given by scientists today would be traceful back to the twentieth century philosopher of science Carl Popper. So who was Carl Popper? Now? Popper was an Austrian British philosopher generally regarded as one of the twentieth centuries greatest philosophers of science. And he identified demarcation as the chief problem in the philosophy of science. Again, how to judge science separated from from pseudoscience, separate the sin from the virtue. Here to draw a really firm line in the sand that we can stick by and judge everything accordingly. And he thought he came up with an answer to the problem, right, yeah, yeah, he thought he came up with with a pretty solid answer. And really I was reading about his life like he stuck to his guns, like towards the end of his life, you know, he had he had He had plenty of critics who said, actually, just doesn't work, blah blah blah. We'll get into the specifics in a second. But he was devoted and he would he spent his time either clarifying what he had said or shooting down his critics. So, yeah, he's he's specked with his guns on this. But what was his answer? How can you tell the difference between science and pseudoscience? What qualifies something as real science? Yeah? What is what is the litmus test? Right? The answer he gave is falsifiability. So what does that mean? So, according to Popper, in order for a proposition right or wrong to be scientific in nature, it has to be falsifiable, meaning you have to be able to describe empirical results, test results in the real world that would show the proposition to be false. And then in order to to strengthen the theory, to build confidence in it, you have to continually seek these exceptions to your rule. You have to keep looking for ways to break your theory, and you have to fail to attain them over and over. Yeah. And this means there has to be such thing as a critical test for any given proposition proposition in order for it to be scientific in nature. Right. Uh? And so let's give some examples in in science, just throughout a theory what the rule is, and then explain how how could you falsify it? So here's one. Einstein's special theory of relativity says the speed of light and a vacuum is the same for all observers. Now, if you could get people in spaceships moving at different speeds to measure the speed of light and a vacuum and get different results, than special relativity is wrong. It's falsified. The theory is, in principle, falsifiable. Another one would be how about common descent. Uh. Common descent says that all life on Earth is related and it evolved from a single organism known as the last Universal common ancestor or LUCA. So if we looked at the genomes of plants and animals and bacteria l the different kingdoms of life, and we found that they had all completely different genes and use different genetic tools to accomplish the same basic survival tasks like say metabolism, metabolizing sugars or something, this would probably falsify common descent. It would make it look like the kingdoms of life had multiple different origins. But that's not what we find. So there there is support for common descent. And here's one example that's often was often touted by Paper himself. So astronomers of the nineteenth century looked to the the the orbit of Uranus. Okay, something seemed a bit off here, so two separate astronomers they pointed out that the orbit of Uranis could be explained via Newtonian physics as being caused by a seventh and previously unknown planet, which of course turns out to be Neptune. Astronomers uh subsequently discover Neptune, and it's exactly where these two different astronomers predicted that it would be. So Papa argued that in this Newton's theory was subjected to a critical test and it passed. But critics would have a different view of this. Critics such as uh Emmor Lactose point out that if they'd been in error, if the if the two scientists here had been wrong, if we hadn't found Neptune exactly where it is, we wouldn't have thrown out Newtonian physics right. We would have looked for other possible culprits, any of the number of reasons that those that their their their theory here could have been wrong. So it was hardly a test of Newtonian physics at all. The falsification corroboration disjunction might very well, just be too simplistic. Yeah, and that's true that there are plenty of criticisms of the poparian Is that the word poparian the the falsification criteria in the philosophy of science. But but this has been one of the big ones that people have have latched onto over the past century. Now to continue exploring falsification. On the contrary, imagine what it's like to have a proposition where you can't come up with any in principle empirical test that would provide strong evidence against it. If you have something like that, this is not a good thing. So imagine a psychic medium claims to get information from the spirit world. Okay, well, well, let's come up with some tests for this. Let's say, let's test the information that he's getting from the spirit world and find out if it accurately reflects information about dead people that he wouldn't have been able to know. He can always say, well, actually, wait a minute, my powers aren't going to work in the presence of the negative energy created by skeptics. Uh so, well, well, maybe we can put some believers in place and blind them to the test and see if you're getting accurate information. The psychic could still say, well, wait a minute, there are also malicious spirits who are responsible for feeding me incorrect information. Uh so in in the end, there is no evidence that could really count against his powers. Anything that could count against it is explained away. Yeah, you can see this with a lot of supernatural ideas, like one of the big ones, of course, one that I often think about is the hand of God. Uh. Analogy here, So, if God exists outside of our universe, all right, if he's outside of our universe, we can't really do anything to disapprove or prove, right, because he's not a part of the observable universe that we can test and we can measure. Now, it's been argued that if the hand of God then reaches into our universe to do things you know, uh, you know, create life, turn a city, to solve whatever, then that hand has to interact with our universe. It has to interact with atoms and molecules, and therefore we would be able to measure a supernatural presence, a presence from the outside reaching into our own by the way it moved. Our molecules are atoms our world. Oh okay, so that makes it sound like the presence of supernatural interaction should be in theory testable. But when you bring that up people because because then you say, when we've ever observed that, people will say, oh, well, he doesn't have to he or she does not have to move the molecules. And then but then you're just saying, oh, well, then they don't have to obey any of the laws, and so it's super untestable. Right, You're removing all possible conditions that could falsify what you're claiming. Right, it kind of becomes like an argument between kindergarteners about who just blasted who with a laser gun on the playground, Like they can both deny that they've been vaporized by a laser gun based on, uh, you know, increasingly preposterous ideas about how the laser gun worked and what kind of imaginary armor they were wearing. Right, But of course, theories that are unfalsifiable in nature don't necessarily just appeal to the paranormals, psychics and you know, ghosts and aliens and stuff like that. You could also have secular unfalsifiable theories. How about this one, We are living inside a computer simulation? Oh yeah, I love this one. Now, there might be some ways that smart people could come up with to test whether not this is true. You could say, well, you know, on a computer simulation, we'd expect to find X. If we don't find X, that's evidence against it. Maybe, But as far as I know, there's no test you could perform to falsify the statement that we're living in a computer simulation. There's no way to prove this isn't correct. And thus it's just sort of like one of those things. Well that's interesting to think about, but it seems unscientific in nature, because if we're in a perfect simulation, we're in a perfect simulation, and how would you possibly see outside of it? It's um, it's kind of like this. Uh. There's a fabulous description of human sight that was related to me over the weekend, and that's the idea that when you look at something with your through your vision, um, you're essentially regarding a timeline of the evolution of human vision. So the corners of your eyes, you you're encountering just blurry shapes, less color, less detail, and as you move in towards the center of your eye, that's where you and actually make out the details and and and very precise movements and changes and and so it's a it's a timeline that converges at the center. But then that makes it kind of difficult and not impossible to envision things further along in the timeline because it's not a linear system, you know. Huh, it's a it's it's closed to us. I guess if that makes sense. That's a very interesting statement. I've never heard that before. Yeah, yeah, I keep keep thinking about it because it's I think it's appliable to a lot of things, a lot of topics concerning the limits of our of our observation, the limits of our of our experience, completely unrelated side note. Did you know that if you have people hold up colored flags at the very edge of your vision, you will not be able to tell what color they are? Oh? Yeah, well that makes sense because to go with the timeline analogy, you are seeing out of your corner. You're seeing with a very primitive form of vision. But we have the illusion that the corners of our eyes have color to them when you look out, Yeah, my peripheral vision has just as much color as the center of my vision. You can test this and show it to be false that statement is falsifiable and has been falsified because when you hold up these red flags at the very edge of your vision, you can't tell the difference between red blue orange. Try it out. Yeah, yeah, no matter what your memory says, because your mind is up stitching it all together into some form that makes sense at least you know, at a glance. Okay, so we've got this criterion here for for the demarcation problem. Real science is falsifiable. It makes predictions, and it says, if this were true, my theory would be false. Ideas that don't conform to this are in our experience, in our experience, incredibly annoying to interrogate. And also, I would say, in our experience, do not generate accurate predictions, technologies, or new knowledge. Yeah. Yeah, because if it's just if it's an idea that you can't test, you can't prove, you can't do experiments on it. All you can do is just sort of is either nod along or shake your head. You're not gonna conduct any experiments and learn something more about the the the inner workings of reality. Yeah. One last distinction I want to make before we start to get to this weird world of the idea of post empiricism. So there's another type of empirical theory of science that's simply a corall area I would say a falsification, and that's verification. And this is actually the older theory. So it's they're both empirical. They're really two halves of the same coin. Right. But with verification, you make a positive prediction and then you test to see if that's the case. So my prediction is that all cows on Earth are brown. Um, so you go out and look, and let's say you find some brown cows. Oh, what do you know? My theory is correct. So you can sort of see the problem with this. You can keep testing and looking for brown cows and finding brown cows, and if you were to regard these the fact that you keep finding brown on cows as an evidence that your theory is correct. Instead, what you should be doing is looking for non brown cows, and you keep looking for them, and eventually if you find a non brown cow, then your theory has been falsified. Right. It's like finding a black swan, Yeah, and then it changes what you know about swans as they actually exist. Now, of course, the fact that all the statement that all cows are brown is wrong. That is wrong, even if it is formulated in such a way that it could be falsified. An unfalsifiable version of the same idea would be cows that appear brown to all observers and instruments are nevertheless not really brown. That that is worse than being wrong. It's not even wrong, it's unfalsifiable. But so one takeaway from this, of course, is that you never actually verify a theory under the criterion of falsifiability. There's no such thing as one confidence that a theory is correct. You just keep building up higher and higher levels of confidence every time you try to find an exception, every time you try to falsify it, and you can't. Yeah, So that I mean, in that sense, the boundaries of scientific understanding are constantly shifting, the constantly changing um at least you know in the realms beyond like extremely verified fact. Right, But his red wine good for you? Is coffee good for you? This is a line that is that is continually changing. Right, And that's a problem because that that that question is not well defined. What do you mean good for me? On average? How do you compare the different goods versus bads, goods and bads? What are studied by science? All right, we're gonna take a quick break, but when we come back, we're going to get into post empiricism. Okay, So we've established that some scientists and philosophers of science have latched onto this idea of falsifiabile or at least some version of empirical confirmation, as as the criterion you use to tell science from pseudoscience. But are there any scientific problems that would lead a non quack that would lead a respectable scientist who does real work with with real data, to propose a non falsifiable hypothesis. Actually, there are some cases where we have very smart, very respectable scientists who are doing work on hypotheses that are widely agreed to be non falsifiable, at least today. And so how about fundamental physics. What's at the bottom of our physical theory of the universe? Well depends on who you ask, But if you ask a certain portion of the scientific community and the philosophic community, they will say string is at the bottom of everything. Yes, And we're of course talking about string theory. Now I know what you're thinking out there, are you thinking, Hey, Robert and j I didn't sign up for string theory on this episode. While you're getting some string theory. But well, we're gonna blow through just a very quick definition of what it is a reminder of what it is so that we can proceed. And uh, we're we're gonna be fairly limited in this, I think, yeah, yeah, yeah, We're not gonna go in too deep on this. Uh, I mean you can really leave it at just imagining a cartoon character and a sweater and what happens when someone pulls on the threat at the bottom of everything unravels. That is true, that is the full scientific definition. But but to go a little deeper, Um, okay, So you have particle physicists to define elementary particles or fundamental particles as the smallest building blocks in the universe. In other words, particles such as leptons and quarks have no substructure. There As small as it gets, you can't split them up. Now, that's not the case for string theorists to think we need to venture deeper or smaller than our current technology allows. So they propose that each so called fundamental particle fundamental particle actually contains a tiny vibrating one dimensional loop of string. The vibration of the string determines the charge and mass of the greater particle. So superstring theories take this idea and build the entire universe from the bottom up. Uh And it's it's a challenging task. And that's why we speak of string of theories in the plural, because there are several different string theories that attempt to make it all work. At least ten dimensions are called for um. A lot of math physicists proposed that any dimensions beyond time and visible space are folded up out of sight into these you know, very complex uh, extra dimensional shapes that you often see are rendered both computer graphics on string theory articles, tiny extra dimensions that that that we can't even measure. They're they're just too small for us to perceive, crawling with shadow creatures that come out to grab children. Um. So and and it is and is that that what indicates a superstring theory is still developing, meaning that physicists continue to work out the kinks in the individual stringth theories, but they're eventually What they're aiming to do is is fulfill Einstein's unrealized goal of unifying general relativity with quantum theory. And that's why string theory is also sometimes called a theory of everything, because it would serve someday as a foundation for all future scientists, scientific discovery, and innovation. The idea that it is an incomplete section in this grand bridge. Yeah. So another way string theories often characterized is that that it's a unification attempts. It attempts to bring together macrophysics, things like relativity you know that happened on huge energies and and and scales with microphysics, the stuff in the quantum world, you know, very very small. Right now, we have strong theories of microphysics that explain very well what we see at those scales, and we have strong theories of relativity that explain very well what we see, you know, with gravity at huge scales. But they just don't mesh together very well. And so string theory would attempt to explain all those things with one underlying theory that that implies both of them. And in reality, the theory is just a set of mathematical models, right It's mathematical models showing the behavior of these strings and how they could produce the effects of the universe we see at these different scales. But there's a problem, right. String physics phenomena are too tiny to observe even with our most powerful experimental instruments. They can't be found by our particle colliders or anything else were likely to build in the near future. So we can make a mathematical string theory model that very beautifully explains everything we already know, but we can't use it to predict any new physical results that we'd be able to detect and use to confirm or falsify it. So that's sort of a problem. Right Is this still science? Wait a minute, now, if we're just coming up with mathematical instruments that explain what we already know but don't make predictions that we can experimentally test, well, is it science and is it useful? Yeah? It's It sounds like it's like putting the car in if not parked, then at least neutral, you know, it's it's going to stop moving after a while, right right? Uh, here's another one. How about cosmology? Oh yeah, what's the ultimate nature of the universe. It's a big question with big answers, Big answers that we often cannot test. Um generally cannot test and going you on one side just say the existence of God or God's but also you get into multiverse theory, the idea that our universe is just one of many and essentially the library of babble, right right, Yeah, so it's that movie multiplicity. Wait, what was that movie? Is that the one one more jetly kills all the other jet leads to game power? No, I think that's the one. That's a really good one. Though, now I'm thinking, what's the one that has lots of Michael Keaton? Yeah, that the clone Michael Keaton's I think it's multiplicity, Okay, yeah, no, no no, no, I was confusing it mentally with virtuosity. The one oh that has with the Russell Crowe is like a synthetic human clone. Yeah, and Denzel Washington, Yeah, yeah, each other. I just remember he had like there's a blue Blood or something like that. Well, anyway, like string theory, that there's this idea of the multiverse that's pretty much untestable. It's but it could be a very elegant outworking of the data we already have. So we have a bunch of observations. We say, if there were many, many universes. It would explain some of the things we see. But we can't make a prediction based on the belief in the many, many universes that we can test. At least there's not a clear one. In fact, I think I have read some physicists suggesting that multiverse could maybe be potential really tested in theory, based on something about spacetime geometry. But I think that's an ongoing debate that I don't fully understand. Yeah, a lot of this kind of it boils down to the prospect of building a bridge into the darkness, and how far into the darkness are you willing to build that bridge accepting that the necessary substructure will be there? Right? Okay, Well, in this case, if we are talking about science, and you know, real science and maybe multiverse cosmology or string theory being some people would have a problem with that statement exactly. No, no, no, I'm saying, if we consider these things science, uh, it seems like we need to sort of revise what are demarcation problem solution is right, assuming we were starting with false liability, which a lot of modern philosophers of science probably wouldn't um. And so here's where we get into the idea of post empiricism, the idea of so just meaning after empiricism, after only being based on observations and physical tests. And I want to talk about a theoretical physicist turned philosopher named Richard Davitt who has studied and written in favor of the concept of post empiricism on behalf of string theory. And he he had this interview with three Am magazine that was published in July. He but he also wrote a book called String Theory and the Scientific Method, and he tries to make a case for a new sort of philosophy of evaluating the scientific merits of theories that isn't just based on empirical testing. Uh, that sounds kind of crazy, right, But let's see what he has to say. So, you've got string theory. You've got this problem that you can paint a self consistent picture of the mathematical properties of strings. And if they existed, they'd answer a lot of questions, right, they would help unify our view of physics. But there's currently no way we know of to directly detect strings or their effects. So in what sense is string theory different from saying invisible acid gremlins push all the particles in the universe around to produce the effects we interpret as microphysics and general relativity. Is it any better and and Davitt would argue that these are not equally valid claims, that string theory is actually much better as a scientific claim, even if it's not empirically testable. And the thing is that that feels like a true statement, right, Yeah, but not everyone would agree. So instead, Davitt thinks that even in cases where you can't falsify a theory empirically, you can establish confidence in the theory with the use of philosophical and probabilistic arguments. Sort of about the research program that produced the theory. It's sort of a meta science. It's judging the quality of science by the scientific situation that created it. Okay, So let's try to give some examples of the arguments he would give on behalf of something like string theory. One argument is the lack of alternative theories. Okay, So it kind of goes back to Holmes logic. Yeah, it's it's the only game in town. Davitt says, string theory is the only theory that integrates into one overall theory. Our topical understanding of high energy physics based on gauge field theory and our understanding of cosmology based on general relativity. So he's saying that there just aren't any other theories that explain all this stuff. It's the only one we've come up with that seems viable. And Dovit also argues that in the past, when we had no alternative to a consistent theory, that theory was often later shown to be correct. So there's sort of a precedent for saying, well, when scientists are working on a question and they come up with a theory that answers the question, even if it's not empirically testable at the time, we later learned that they were right if it was the only theory they could come up with. Right, Yeah, and that makes sense, right, You to proceed to actually push forward, sometimes you have to envision what that reality may be. You have to create this model and then see how it plays out over time exactly. So he also says, look, it has proven conceptually useful. That's a second argument. So Dobvitt suggests that string theorists have given physicists insights into other problems in physics that they weren't originally setting out to solve when the theory was conceived, so it explains more than it was originally meant to explain. That seems like another good tick in the evidence column. In other words, it's not predicting a physical outcome that we tested, but it's sort of yielding some mathematical results that that that fit together in interesting ways. And then the last major argument he gives is sort of that the way I would put it is that it grows from proper scientific soil. You know, it's not like saying, uh saying acid gremlins. That it comes out of a research project of high energy physics. And this research project of high energy physics has generated all kinds of other ideas that have been testable empirically and have been accurate. All right, well, all three of these are making sense. He seems logical, sure, And he gives another example from the past. I think it's when we mentioned earlier, but he says, you know, if if you look at the past, what about atomists, people who thought that the matter in the world was made of atoms. According to Davitt, scientists thought that the world was made of atoms long before they had any way of experimentally confirming predictions of atomic theory. Of course we have those experiments now, but atomic theory was the only serious theory of matter on the table, so there were no alternatives. It yielded insights that it didn't set out to yield, Like, it explained more than it was designed to explain. That's his second case with string theory, and he says it emerged from a research program that had success in making other predictions that were empirically verified, you know, not from It didn't come from demonology. It came from chemistry and physics. So that's interesting to me. Now we're going to get into some serious criticisms of this way of thinking, but this does kind of broaden the picture and suggest that maybe our way of thinking about what's a good scientific idea should be more complicated than just saying like, well, it's something where you can do a physical test with an observable result, and you can say what would falsify it? And you show that that's not the case. Yeah, it, you know, and I can't help but think of examples such as geocentricism, uh, hedio, centrist is um. You know, in terms of all of this, you know, certainly false theories that we eventually realized, oh, well, the Earth isn't the center of the universe. The Sun is at the center of the universe. And yet all those theories were still they were still useful models thinking about the structure of the Solar system before we really had a more nuanced understanding of what it was. But with something like string theory, it's such a complex and robust uh creation. You know, it was such a robust theory that it seems like there's there's much more on the line, and there's much more room to potentially create something that is not so Yeah. Well, and with string theory also, should we treat string theory differently than other theories because it's supposedly a final theory? You know, if it's the ultimate theory of matter in the universe, should there be different rules for assessing it than there would be for assessing you know, some theory of genes selection or some other you know, some theory in in biology or regular chemistry or something. Because it doesn't set itself up to evolve, and of course hindsight, but you look back at heliocentricism and you can see its place in an evolution of thought. But but certainly when people are arguing strength theory, they're not saying, well, this is strength theory and hopefully we'll work up to wool theory and nylon theory, you know, or whatever. Like you said, it's it's it's it's argued as a as a as a as a fix to the end of the line. But yeah, that's that's a very good point you make about heliocentrism, because it's like, um, it was less wrong. That was the important thing was that it was less wrong than geocentrism, and though it was still wrong, and it still allowed you to have a pretty accurate understanding of the of immediate solar mechanics. Yeah, so to me, there does seem to be something interesting going on in what David is saying, Like it's not, um, it's not just a bunch of junk. Then again, there might be limits to how far you can extend these ideas he's propounding in in how you're going to define science. It almost makes it seem like it would have to be a case by case scenario. Uh, you'd have to take him on a case by case basis, and that that means there's no absolute rule. It thinks there's just some guidelines and then we have to weigh in on it. Yeah, so I want to read some some criticisms. One of them is the theoretical physicist Sabine Hassenfelder. She responded to this interview that I mentioned, and first of all, she says, flatly, post empirical science is an oxymoron, just flat out there is no such thing. Now, David actually defends himself by saying that he doesn't advocate quote post empirical science, just post empirical theory assessment, which is honest, I have to admit as a distinction which I have failed to grasp thenificance of. But well it's maybe there's something there. But anyway, Hassenfelder, her response to this, had a really good quote that I wanted to read that I thought sums up the attitude of the critics of post empiricism pretty well. She said, quote this non empirical theory assessment, while important, can however only be means to the end of an eventual empirical assessment without making contact to observation. A theory isn't useful to describe the natural world, not part of the natural sciences, and not physics. These insights that Davitt speaks of are thus not assessments that can ever validate an idea as being good to describe nature, and a theory based on non empirical assessment does not belong in the natural sciences. So I think she's acknowledging that maybe there is something to non empirical theory assessment, only in the sense that it might help bridge us along until we can get to a time when there is empirical confirmation. Maybe if we can eventually come up with ways of testing the predictions of string theory. But until but if we don't ever get there, then this assessment is type of assessment is useless, right And then, of course, how do you get to the point where you can test it if you're not working towards that point, you know, you know, just say, oh, accidentally, we're now in a position to test out this theory that we refused to give credence earlier. Now, another voice on this matter that we came across is a cal Tech physicist Sean Carroll, who wrote on edge dot org answering the question what scientific idea is ready for retirement? His answer falsifiability. Um, you know, he he sticks by empiricism, but once a different empirical paradigm, not post empiricism, but post falsifiability. Simply put, and this is a quote from from his paper, refusing to contemplate their possible existence on the grounds of some a priori principle, even though they might play a crucial role in how the world works, is as non scientific as it gets. Yeah, and I think Carol makes a good point. They're like, so there may in fact be strings at the bottom of reality, you know, matter, the universe may be based on strings and and membranes. Uh. And there may in fact be a multiverse. There may be other universes out there and stuff like that. It doesn't make sense for us to say, well, we can't entertain that possibility because it doesn't fit with our model of the solution to the demarcation problem. You know, He's saying, we should have we should be coming up with ways to assess these things, even if it doesn't classically fit the philosophy of science, definition of science. And of course, Carol, he posits a couple of different criteria, so he he still wants to stick with empiricism, but he proposes I think that that it must be what definite and empirical rather than falsifiable. Uh So, that it has to be a theory that is scientific in nature, has to be well defined, it's described in a clear, unambiguous way, and it also has to interact with empirical data in some way, like it has to take into account what we know empirically about the universe, which, of course, like string theory and the multiverse do, they explain what we already know. The problem is they don't make predictions about what we could know in the future that can be tested. Right, So you couldn't You couldn't use it as a way to prop up your own hollow earth theories. Yeah, all right, So what else do we have here in terms of criticism, agreement, etcetera. In the string wars. Well, I've came across a Nature comment piece from December by the mathematician George Ellis in the physic theist Joe Silk called scientific method defend the integrity of physics, and they were taking a stand against post empiricism, or against at least some uses of it. Uh So that they start off by saying that, you know, some scientists now argue that if a theory is quote sufficiently elegant and explanatory. It doesn't have to be tested experimentally. And some examples they give our string theory, the kaleidoscopic multiverse, the many worlds interpretation of quantum reality. That's one. You know, so you've got the the equations of quantum physics. We those are very well tested, we know they're accurate. But what do they mean when you have the you know, the supposed collapse of the way of function or whatever, what do they mean really happens in reality when a probabilistic wave function event happens. Well, one way of interpreting it is saying, okay, every time there's a quantum event that could go one way or another, reality actually splits into different reality and you have different worlds where both are true. Now in the multiverse, right, yeah, different type of multiverse, the many worlds quantum reality multiverse. Another one would be pre Big Bang concepts. They say, you know, trying to do math about what happened before the Big Bang, if that makes any sense, Like what happened before the initial singularity of all existence? Like was it in a giant's pocket? Some marbles on the back of a turtle exactly. Uh. And so they say, if you if you d couple science from experimental false falsification, quote, theoretical physics risks becoming a no man's land between mathematics, physics, and philosophy, that does not truly meet the requirements of any I love that quote. That's a great quote from from the article. Yeah, does it become this own purely? You know? Did it become just an abstraction? Right? Has it left the realm of the natural sciences without yet just because coming a philosophical discussion or or abstract mathematics in in truth, so they make a couple of specific examples about string theory where they disagree with with Davitt's arguments. Um. But then they also go on to say, you know, look, history is full of examples of elegant and compelling theories ideas that lead scientists in the wrong direction. They cite Ptolemy's geocentric universe, Lord Kelvin's vortex theory of the atom, Hoyle's steady state universe, you know, the the eternal unchanging universe. And in the end they say, quote, in our view, the issue boils down to clarifying one question. What potential observational or experimental evidence is there that would persuade you that the theory is wrong and lead you to abandon it. If there is none, it is not a scientific theory. So here they're staking out basically with falsification. They're saying it's got to be falsifiable in in a testable physical a or it is just not science. This is not meeting the definition. And they also mentioned some practical considerations that that are worth considering. One of them is that they say, you know, even if there's some merit to post empirical theory assessment in niche subject areas where we can't perform experiments like string theory and stuff, public discussion of this could have disastrous consequences. It could cause confusion and undermine public confidence in uh in science generally, and especially in politically charged scientific ideas like climate change, evolution, vaccines, GMO safety, all of which are empirically based. But if you start introducing this idea but what waits some science isn't based on empirical testing, You're going to hurt people's confidence in the science. That is, yeah, it ceases to become this this pure engine of learning and knowledge and truth and becomes this more abstract thing where people, if you're always asking, well is driving it? Yeah, people are asking this, Wait a minute, so what is just people doing weird intellectual experiments in their ivory towers that can't be confirmed or denied by by experiments. Um. And then so they go on to say also that claiming the theory is too good for testing opens the door to two genuine pseudoscientists to would claim the same thing about their ideas. My my psychic powers are are just too elegant and too well explanatory, you know, they explain the facts too perfectly to be suggested subjected to this you know, prediction problem. Yeah, this is kind of the scenario you get into the hand of god argument or conversation, the one might have with with someone where you can you throughout the criticisms you point out to where it wouldn't work, But then they can always they can always change the argument until it's it's there's no way to possibly refute it. Right, And so they end by saying the imperimeter of science should be awarded only to a theory that is testable. Only then can we defend science from attack. And to me, these seem like concerns that are a very important part of the conversation about science communication. It's almost more about what you and I do, Robert, But they don't seem especially relevant to me, at least to the internal conversation between scientists about what kind of work in physics is worth doing and how much confidence we should have in ideas like string theory. I don't know what you think about that, but it seems to me like that that's kind of irrelevant. That's more just a public policy conversation. Yeah, I would, I would agree, though. I mean, when it comes to reading about physics, I have to admit I would probably choose to read about theoretical physics before I would read anymore about experimental experimental things. Yeah. Um, And of course we should point out that not all theoretical physics is is removed from experiment. I mean, I think, I think most theoretical physics, you know, they're interacting with particle colliders and and and all the experiments that were out there doing gathering data on But yeah, I don't know. I don't know what you're supposed to do in these cases where where it's not just that string theorists decided that they didn't want to test their their theories. You know, that they are by necessity dealing with a part of reality that we can't access experimentally. That that's just how it is. They didn't design it that way, you know what I mean, Like, they didn't pick it. It's just a problem with our powers. And another thing I think I would acknowledge is that it seems like almost all of these people who are critics of the the idea of post empirical theory assessment, you know, using these criteria other than physical testing, acknowledge that there's something to it. They seem to say, okay, yeah, they would probably admit that string theory has more going for it than the acid gremlin's hypothesis. There, so there is something to the non empirical uh theory assessment. They just don't seem to say that it's enough to call it science. Yeah, you know, I can't help me. Be reminded in all this of nineteenth century German philosopher Frederick of Wilhelm Joseph Schilling's Natural Philosophy Um Philosophy of Nature in German Um. And this is a concept um he developed as a sort of augmentation to science that would allow science to investigate the human spirit, because he saw nature or the force nature and the human spirit or the forced geist as the two great opposing forces in cosmos, with the human mind at the center of everything. So nature, according to two Shilling, is the visible spirit of the invisible spirit of the mind. But again the mind is very much at the center of the equation um. Now he was this This concept was attacked for, among other things, lack of empirical orientation, And indeed a lot of it seems to inge on the investigation of the invisible, the comprehension of the scientific getting unverifiable through the lens of something at least linked to the substance of science. So it's it's hard to I think I thought of that a lot when I was reading over some of the material, because it seems like a good example of sort of bad post empirical science. Yeah, the idea that you're gonna you're gonna, you're gonna take, you're gonna go as far as science will take, and then you're just gonna completely extrapolate it into the unseen um. But then the counter argument is, then, how is that different? How is that ultimately different from something like string theory. Yeah, I mean we're back to the demarcation problem, right, Yeah, Like, what is the rule we're using to tell the difference? I sense a difference to a sense that there's something much more respectable about string theory and multiverse cosmology than there is about the the invisible spirit um. But it's hard to articulate exactly what that is though, though I would say that Davitt's criteria are somewhat useful in that regard that they give you some criteria for saying, Okay, we're not running a test, but here are some characteristics of these theories that do seem to make them probabilistically and historically more likely to be correct than just gremlins or invisible spirits. You know, it reminds me of something else, and that is the the Ian and Banks Culture books, which I know would bring up a lot but but but he managed to fit a lot of science into these, at least in the earlier books. It's established that in this uh, in this culture known as the culture, you have all these ai minds that are really ruling everything, that rule these giant warships, and they make all the decisions and they they do all the heavy thinking and heavy lifting for the humans and humanoids that make up the culture, but they keep the human humans around and they occasionally have the humans you know, engaging and very important roles. And part of this uh it's it's it's uh proposed is because the humans will occasionally make leaps in judgment or in theory that the machines do not cannot, which comes back to that that idea that I put forth earlier about how if you had a pure computer, a pure, pure logical entity doing the science, Um, would there be limitations to that? Would would there be this place where you would need a non empirical jumping logic that only a human who is abound and shackled to their prior beliefs and their philosophies, that only they could make what a what a skeptical engine? You know, a computer of scientific investigation not be able to make intuitive speculations. You would have to have the the the the Devil's advocate computer. Right, Yeah, throw weird ideas out there and then allow for testing. Soh this this veil of testing. Indeed, so one more thing I wanted to mention before the end of this. I was actually inspired to do this episode by reading a really good article on this whole subject of, you know, post empiricism and falsifiability in science by the philosopher of science Massimo Peleucci that he wrote in Eon magazine, which is always one of our favorites around And they're nonprofit now, so if you really like what they're doing over there, you can donate to the cause. By the way. Yeah, but uh so, Peleucci mates makes a point in his approach to this topic. He wonders if what if science is not it can't be demarcated in a way that a word like triangle can. So there's a word triangle that has a very clear definition, has what he would call quote necessary and jointly sufficient properties, and that just means it has a description which includes everything that could possibly be a triangle and rules out everything that is not a triangle. It has three angles that add up to eight degrees um perfect description of all triangles and nothing else. What if science is simply not like that? There aren't statements that are a perfect description of science and nothing else, and rather science is more a concept that is based on what Wittgenstein would call family resemblances in that it's a term like game. Now, could you come up with a definition or a description of what games are that includes everything that's a game and excludes everything that's not a game. Yeah, this is actually something that comes up a lot when I play games, such as my argument that apples what apples to apples? Apples to apples? Yeah, not a game? Um as fun as the other one is? What is it? The one with all the awful cards and it cards against Humanity? Also very fun, but not a game according to you? According to mean, some people would say it's a game. Is chopping would a game? You know? When I was a kid, I really love chopping woods. Some people think that as a chore, but I don't know. I guess it was just fun to swing an axe. Uh, well, certainly that's the thing. You can turn non games into games by establishing a set of rules for your completion of that task. Yeah. Yeah, you can turn things that shouldn't be a game at all into a game. But you could get a room full of people to have a list of activities like chopping wood, apples to apples, a whole bunch of things like that, and say, is this a game or is it not? And mostly I think they'd agree, you know, you'd get general agreement on the on the use of this term as it applies to things. And yet we can't come up with this necessary and jointly sufficient description of what games are. Maybe science is like that. So in a sense, science is a thing that would not be able to see itself. It would not be able to set itself because it itself does not fall into the uh specificity of form that science requires. Yeah, that could be. I don't know. Um, I I find this topic very interesting because I don't quite know what the answer is. I'm not sure how I feel about it. Obviously, I'm not a physicist, so I'm not I'm not working in these fields like multiverse cosmology and string theory, so I'm not even educated enough in them to really judge the intrinsic merits of the ideas, but just accepting that they are very good theoretical solutions. Yeah. Well, I think this is the that this is the appropriate feeling to have about it, because we're talking about theories that take us to the edge of human understanding and extrapolate beyond, and that's that is a place where I think where we can all agree it's okay to feel inadequate, It's okay to feel befuddled and unsure, because that is the nature of the edge. Yeah. Um, so yeah, I guess in the end, like I, I sort of see what Dovid is saying and like his his distinctions do make sense to me. I also see what the critics are saying about that not quite being science, or at least not science in the same way that all the science we really care about is uh. I wonder how that should work out in terms of practical concerns like funding, Like should we be funding uh, using public money to fund string theory research in the same way that we're funding stuff that is being tested and falsified. Yeah. I mean it seems to me you often encounter problems when you start opening up the discussion to the merits of this particular scientific inquiry versus all the others. You know, you kind of get into that hole, why are you doing this when we haven't cured cancer? And then you your answers like, well, this is this is theoretical physicist physics. Here, we weren't going to actually achieve a cure for cancer, as that's not our area of expertise. Yeah, like the the sort of false assumption of a zero sum game in the investigation of science. This is something that comes up a lot, you know, as somebody does a study that has an interesting but not necessarily technological results, and people comment under the article why are they studying this when they could be curing cancer? Right, as though, what the shrimp on a treadmill scenario where it's just become at all, I can't believe it. Our tax dollars are paying for shrimps on a treadmill. And then you ignore the fact that well it's it's it's still advancing science. If it's a you know, it's a valid study, it's just maybe not as as sexy or as a uh you knows, as obvious an advancement. And you don't even know in the future in what ways it may inform future technologies and other applications. I mean, that's always the thing with science. We we don't always know what the outcomes are going to be of learning something. Yeah, as this thing called science continues to creep out, sometimes into snail's pace, uh, sometimes a bit faster into the unknown. All Right, So how about you, how do you feel about this particular topic. And do you think the so called string wars that we're talking about here, do these, as some critics charge, distract from the real bad that should be going on against pseudoscience and the misuse of science by various outlets. Is this kind of the uh, you know, the wars of the of the Seven Kingdoms that are occurring while the White Walkers of pseudoscience marched down from the north. That that is true? Also, I mean, are are we sitting here arguing about what physicists should or shouldn't be contemplating? Meanwhile, we've got alternative medicine peddlers who are at the gates who knows. Uh. We'd love to hear from all you guys and gals about that. And if you we want to get in touch with us, you want to learn more about what we do, there are several ways to do so. First of all, Stuff to Blow your Mind dot Com is the mothership. That's where we have all of our podcasts, videos, blog posts, et cetera, as well as links out to our various social media accounts such as Twitter and Facebook and Instagram. We're active on all of those and Stuff to Blow your Mind dot Com itself has just recently experienced a redesign, so everything's coming together there. It's looking really sharp. 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