 Hello, and welcome back to Beyond Networks, the evolution of living systems. Today, we're going to dive right in. And I'm going to give you some philosophical background in the next four mini lectures here about what I mean when I was telling you in the first lecture that I was giving you a sort of a different scientific perspective on evolution. Is that just my opinion that I'm going to give you? Everybody's entitled to an opinion. I think it was Mike Pence who said this. But that shouldn't be the case. In science, we're supposed to argue based on evidence and facts. And very often, we assume that there is only one way to understand reality. So what we need to do for me to be able to explain to you what I mean by a perspective is we need to dive into one of the main branches of philosophy. Here they are. These are the three main disciplines in philosophy. One is metaphysics, also ontology. So that's the sort of branch of philosophy that's busy with what exists. Then there's ethics, aesthetics, the branch of philosophy that has something to do with human values. But what we're going to look at today is the theory of knowledge, which is called epistemology. And we're going to think a little bit in this and the next few mini lectures about how we actually gain scientific knowledge. So epistemology is the theory of knowledge, especially with the regard to the methods, the validity, and the scope of the knowledge. And the distinction between what is justified, believe, and opinion come back to that. So I'm not just giving you an opinion here. I think what I'm going to give you has some justification. And this is what these lectures are going to be about. So traditionally or naively, when we grow up, before we become scientists, what we think is that there is some sort of truth about the world out there. We live in a world that doesn't depend on our existence. It goes on when we don't exist. It does things we don't want it to do. So there's some sort of objective reality. The truth is out there, as they said in the X-files. And what do you do when you apply the scientific method? You could naively think, what that is is it's like an algorithm. So you apply this method, and it gives you the truth about this reality, or the causal structure of the world that you live in. This is what you do when you do science. And it doesn't depend, in this view, who is doing the science. If you apply the scientific method correctly, you will get closer and closer to the truth. Some people believe you can even get to the truth. Others believe that you will just be better and better closer and closer to it as time goes on. And the scientific method kind of filters out the sort of human aspects, the messy everyday aspects of doing science, and gives us this sort of absolute and certain and objective knowledge. I'm not drawing any sort of strawman or cartoon here. This is one-to-one, the view that is publicly defended by certain scientists. One of the most famous is the physics Nobel Prize winner, Stephen Weinberg, who's written several books about this. And he's in the search, and often the search of the final physical theory that he believes will represent a sort of a complete and accurate description of the universe. But he's not alone, of course. Everybody really starts out as a sort of a common-sense realist. This is what this is. So basically, there's a world out there. And this particular view that, in the words of philosopher Hilary Putnam, there is exactly one true and complete description of the way the world is. That view is called Objectivist Realism, OK? And so Putnam actually, I have to say in this book that I'm citing here, is criticizing this view. And we'll see why it doesn't really hold up, although it is sort of the intuitive way of thinking about the world. And it was a way that was defended very famously here in Vienna about 100 years ago by the philosophers of the Vienna Circle, the logical positivists. Marchlich is especially famous for being murdered on the stairs of the main building of the University of Vienna by his PhD student. We're not quite sure if it had something to do with the student being psychotic, a Nazi, or because Schlich actually slept with his girlfriend, maybe all three of them. But it's a pretty fabulous death for a philosopher, quite unusual. Philosophers rarely get shot, although they say outrageous things sometimes. Neuerab, Rudolph Karnav, all these people formed a group that met every week to discuss how you could ground knowledge in reality and how you could get rid of all the what they called metaphysics, which was just idle speculation. So they said, only statements that you can actually verify through empirical observation are even meaningful. So all your feelings, your love for someone else, not meaningful in the view of the logical positivists. Okay, pretty radical position, but they came up with very strong and critical arguments. They were critical of each other as well. And they disagree on how you could verify empirical statements about empirical observations. It very soon turned out to be an impossible project, unfortunately. And another Viennese philosopher, who's maybe the most famous and well-known philosopher of science among scientists today, Karl Popper came up with a criticism that was pretty devastating and basically proof that the verification of such knowledge, empirical observation is a sort of a logical fallacy. So positivism is logically inconsistent. Instead, he said, you can't verify a hypothesis that you have, but you can falsify it. Okay, so if your hypothesis states something that is testable, then it can be refuted by the evidence. Okay, and that is not a fallacy. So we cannot really know whether our theories are true, but they are scientific theories if you can falsify them. A very different view of how science creates knowledge. And this basic view is still true. We think today that Popper's view was very over simplified, maybe the way that he thought that science works, but the basic assumptions underlying his falsification and positivism still apply today. There are more problems with certain, the idea of certain and objective empirical knowledge. If you think about it a little further. So one problem, it's a problem of sensation. All empirical knowledge needs to come into your brain through perception, okay? And so what you see here is not a swan. It is a picture of a swan that is processed through your sense of vision, through your eyes and your brain, and all you can experience is that image, that representation of the swan. You cannot represent, you cannot access what Immanuel Kant called the swan an sich, the thing in itself that's out there somehow in that real world that we assume exists. So that's a problem because to make a long story short, our senses, they may not deceive us. They may have evolved to be pretty good at detecting the relevant features of our environment, but they are not absolutely trustworthy. And what's very important, we cannot make, we cannot prove that we can trust our senses, okay? So whether our senses are trustworthy enough is itself a sort of an empirical investigation on which you cannot ground empirical investigations on another empirical observation. So the sort of range and the reliability of our senses limits what we can know in the first place, empirically about the world out there, okay? So that's one problem. The second problem is a very famous problem in philosophy. It was first stated by the Enlightenment philosopher, David Hume, ultimate empiricist. And it goes as follows, you observe a bunch of swans and they're all white, okay? So after a few dozen swans, you probably conclude quite reasonably that all swans are white. This is the problem of induction, of inductive generalization, okay? So what you're doing here is you take a sample of swans, it's a limited sample and you say, you make a generalization and say, the class of all swans in the universe, they are all white, okay? But this is very dangerous to do because you can't actually conclude this. It's not logically consistent. And it's dangerous because, as in the case of the swans, of course, Willem Flaming, the Flaming traveled to Western Australia in 1697 and discovered this species, Cygnus Tratus, the black swan. This, by the way, gives the name to Nassim Taleb's idea of the black swan. It's an unexpected, unpredictable event. Nobody could predict that one day, a black swan would be discovered. Nowadays we know there are plenty of black swans. They've been introduced to other continents. So based on that limited sample that you had, you cannot generalize with certainty to all swans. That is just because we are fundamentally limited beings and our experience is always by definition because of that limited. So it doesn't even make sense to talk about, we could have knowledge about the universe in total because we cannot. We would have to be unlimited in some way, okay? So our inductive generalizations are always fallible. They could be wrong. And what's even worse, we're not gonna go into this today because we don't have time. You don't know when you can rely on them and when you can't. But that's not all. There is a third problem. And that is the problem of theory ladenness. That brings us to another very important philosopher of science. Thomas Kuhn, who came up, who was one of the main philosophers apart from Willard Van Orman, Quine, who came up with this idea of theory ladenness. And it's a very simple idea. It just means that you're biased by what you've experienced before. So any observation or interpretation of data that you make depends on what you've experienced before. For example, look at this beautiful picture by the Hubble Space Telescope with the three pillars of creation in the Eagle Nebula, about 6,000 light years from the Earth. What do you see here? You know, because you've seen it in the news probably, is a huge cloud of gas in space. But just think about all the things you need to know already before to make this sort of interpretation. You need to know about the existence of the Hubble Space Telescope. This picture doesn't show you visible light, but it shows you infrared and other ranges of the spectrum as well. So the green parts of the cloud are hydrogen, the blue, oxygen, red is sulfur, okay? And so this image doesn't really, this is not what you would see if you would look at this patch of space with your naked eye. So you need to know the theory of optics. You need to know about different wavelengths of light. You need to know about the chemical elements, these colors are representing. You need to know about the evolution of stars and so on and so forth. This is a pretty contrived example, of course, but if you think about it, if you just look outside and check what the weather is, you already need all kinds of sort of assumptions to be able to reliably conclude it's raining, okay? So we're bound to our biases and assumptions and we cannot basically, that's the basic truth, we cannot step out of our heads and see the world in a truly objective or maybe God's eye view, we'll come back to that. Observations and interpretations are always dependent on our assumptions and those assumptions they rest on previous experience and knowledge we have about the world. So one of the Vienna circle members, Dr. Neuerhardt, he said, the scientist is like a sailor that is rebuilding their boat while they're sailing on the ocean. We cannot just jump into the ocean and start from scratch. So what we have to conclude here after this very brief argument, I have a lot more to say about this in my philosophy course for scientists that I will put online, hopefully in the summer. What we can say is that the truth may be out there. We can be realists about the world, it may be, but we'll never have objective and certain knowledge of that world, okay? And this is a philosophical stance that is called fallibilism. And it makes a lot of sense if you go through this argument, we've gone through it very quickly, but it's very new. It only exists for a few hundred years and has only become popular over the last few decades, even after positivism turned out to be inconsistent. Before that, people were infallibilists or foundationalists. They believed that you could ground scientific knowledge in some of objective argument or criteria. But we know we're pretty certain, we can't be entirely certain, of course, that empirical knowledge can never be absolutely certain. But that's the point, right? Science is not about certainty. This is very important, I think, for scientists to know. If you want certain knowledge, go to church. There you get the truth. You don't know questions asked, but of course science always has to be able to revise its beliefs based on new evidence that may be coming in. And that brings us to the dynamics of how science progresses and back to Thomas Kuhn. So we're gonna talk very briefly about Kuhn's view of what he called scientific revolutions. Kuhn said, science usually progresses kind of steadily by accumulation of new insights and facts. So he called this normal science a little disparagingly. He said, what scientists are doing every day is puzzle solving. A puzzle is a small problem. You can solve it without a scientific revolution. But at some points in history, a classic example being the transition from a geocentric worldview of Ptolemy to the Copernican system, heliocentric system of the world. Sometimes these sort of periods of conceptual continuity that are interrupted by periods of revolutionary science. And Kuhn famously called this a paradigm shift. Never quite defined what it exactly is, but that's quite a famous concept in the philosophy of science. And he said, people who work before and after such a paradigm shift, they cannot even talk to each other or sit at the same table, which is the meaning of this Latin word, income and surability. Their concepts, their frameworks of thinking are so different, they cannot understand each other anymore. And the actual meaning of scientific propositions and truths changes through a revolution like this. New paradigms also allow us to ask new questions, look at a problem with completely new eyes. And this is where these perspectives come in. Of course, from this point of view, we would say before and after the revolution, you have a different scientific perspective. This was taken up by historians and sociologists of science especially, which argued that in fact, scientific knowledge is not discovered, it is created. So scientific knowledge is some sort of social construct. And there are different variations of this, a very strong version that we're gonna talk about briefly towards the end. We're not actually gonna talk about this. I talk about this in my philosophy course. I get confused sometimes about my different lectures. We're not gonna talk about this, it's fact constructionism, constructivism. So the idea that we're actually building facts, but you can argue that radioactive radiation happened before we had the concept of radiactivity and so on and so forth. So you can come up with a sort of a weaker version of social constructivism that says, okay, science is history dependent. It has a historical path dependence. The application of the scientific method, the questions we ask and the way we interpret the answers, they depend on our historical and social circumstances. We are part of our community. And so we cannot only step, we are unable to step out of our own heads, but we're also unable to step out of our social and historical context. And further on, the contingency hypothesis says that reality seems capable of sustaining more than one account of it. So at different times, but also at the same time, different scientists will have different perspectives on the world. So basically, oh, this is an interesting sort of aside to this, of course, constructivism is reflexive. It's itself just a construction. The point is not to come up with a theory of reality in constructivism, it's just a criticism of realism apparently, all right? So what is happening here, okay? So we have two different views and we have to admit, okay, they both make sense, right? In some ways, there is objective is realism that says there's exactly one way, one complete and accurate way to describe the world. And there is constructivism that this construction knowledge is constructed. It's not discovered and depending on where and when you work, you will have different views. Of course, this is a problem, this is a paradox. These two things cannot both be true. And so for a long time, there was a huge debate raging, it actually was called the science war. So I'm sure you've never heard about this before in the 1990s, sociologists of science attacks, scientists and scientists barely noticed them. But they had some really interesting points to make that we needed to address because we cannot deny that science is sometimes, the process of doing science is flawed, it's context-dependent. Luckily, and this is the topic of the next unit, there is a middle way, a way out of this, a compromise, okay? And this compromise is called perspectivism, realism with perspective, perspectival realism. I'm gonna use the next mini lecture to take a wonderful book by Ron Geary, contemporary philosopher of science, it's called scientific perspectivism and introduce the concept. And then we're gonna sort of enrich that over the following two units, to make it practical and to come back to the question, how can you justify scientific truths in this view? So what perspectivism does is it realizes that the problem is not that realism, the belief that there's a real world and constructivism, the belief that knowledge is some sort of social construct, they're not incompatible, that's not the problem. You can believe in the real world, that it's out there independent of your mind. And in your inability to comprehend it in its entirety, because you are a limited human being, any limited being will have this problem. So the problem is not realism, the problem is objectivist realism. This idea that we apply the scientific method like an algorithm and we get independently of what's happening in history closer and closer to the truth. We need to leave this behind and that opens the door to look at the world with different eyes because we're all different limited beings. And this will be the topic of the following lecture. Thanks for listening. Tune in soon when I upload the next unit.