video
Episode
Why Philosophy of Biology?
Philosophy of Biology has two sides: the process of science and the content of biology. We address key questions. What is the nature of life? How does evolution work and what are its challenges? How to consider race, sex/gender, cognition, culture, morality, healthcare, religion, alien life and alien intelligences.
Contributors
- Robert Lawrence Kuhn
- Closer To Truth is my life passion. For more than 25 years, and intensely since 2006, I’ve explored on Closer To Truth the big questions of raw existence and human sentience in three pillars: cosmos, consciousness, meaning. Cosmos – the mystery of existence from fundamentals physics to beginnings and ends of the universe. Consciousness – the mysteries of mind and brain, free will, personal identity, even survival, and ESP. Meaning – the challenges of theism, atheism, agnosticism, and the philosophy of religion. But something has been missing, and it’s bothered me. Something between Cosmos and Consciousness. Closer To Truth now begins a fourth pillar: Life. We’ll cover all aspects of life, from anthropology to astrobiology and those are just two of the “A’s”. To begin, to explore a fresh way of thinking about life, I focus on philosophy of biology, and address three kinds of basic questions: 1. What is the deep nature, or essence, of life? 2. How did life on Earth come to be as it is? How did we humans come to be as we are? In other words, how does evolution work? 3. How to consider biologically-based issues, such as race, sex and gender, cognition, culture, morality, healthcare, religion, alien life, death & more? Why philosophy of biology? I’m Robert Lawrence Kuhn, eager to begin Closer To Truth’s new pillar: Life. We begin Life with biology, because biology is the fundamental science of life. And we begin biology with philosophy of biology, because a philosophical perspective clarifies concepts and sharpens issues. It was only in the second half of the 20th century that philosophy of biology emerged as a scholarly field in its own right. How to fathom the field? Learn philosophy of biology, its scope and ways of thinking? I go to the source: I meet philosophers of biology, the founders and pioneers, the thought leaders. I start with one of the pioneers: founder and long-time Editor of the journal, Biology & Philosophy, Michael Ruse. Michael, I’d love to hear your perspective of the reasons for philosophy of biology, and something of the development, of course, of the field.
- Michael Ruse
- So, if you go back to the 1960s, which is when it started, suddenly biology had reached a kind of level of maturity which was significant. When I say “biology,” I mean, particularly evolutionary biology, because although, let’s say, psychology is important, it’s not something which immediately gives rise to philosophical problems, whereas evolution bursts with them. Suddenly, biology was no longer the—what shall we say—the poor little cousin of the physical sciences: it was doing its own thing. No, I wasn’t the only one. There was David Hull, in Chicago, particularly. And other people like that, Bill Wimsatt in Chicago, and then, of course, ten years later, the younger generation like Philip Kitcher, and Elliot Sober came along. In many respects, far more sophisticated than we, but we’d already been there, doing our bit. So, this was philosophy of biology, for me. And here I am, 50 years later, doing the same stuff.
- Robert Lawrence Kuhn
- One book that helped establish philosophy of biology that made philosophers aware of the new field is The Nature of Selection: Evolutionary Theory in Philosophical Focus, published in 1984. I meet its author, Elliott Sober.
- Elliot Sober
- Let me start back in 1859, with Darwin’s publication of The Origin of Species, and from the get-go, it was clear to everybody that this theory had immense philosophical significance. How is the belief in God related to Darwin’s theory? What does it tell us about human nature? I mean just from the beginning, everybody recognized this as a fundamental thing. What’s happened since the 1960s is a continuation of some of those questions. But new questions became interesting. One of them was the result of a big controversy about the units of selection problem. Does natural selection just involve organisms competing with other organisms in the same species? Do groups of organisms compete with other groups? That would be an example of group selection. That was a giant debating question among biologists then. And philosophers—myself included—recognized that there were a number of important philosophical issues that were raised by these questions about reductionism, and so on.
- Robert Lawrence Kuhn
- Why did the units of selection problem trigger such controversy? I meet an expert on evolutionary structure, including the units of selection and adaptation, Elizabeth Lloyd.
- Elizabeth Lloyd
- When I went to Princeton, to graduate school, I was interested in philosophy of biology. I had written a paper my first year there, and Bas van Fraassen told me it was publishable, so I thought, well, this is great. It was about the theory structure of evolutionary biology. But, nevertheless, I was told by the chair of the Princeton department, you can’t write your dissertation in philosophy of biology — it’s not a field.
- Robert Lawrence Kuhn
- Wow. Uh-huh, because philosophy of science was the field?
- Elizabeth Lloyd
- Philosophy of physics was philosophy of science, philosophy of science was philosophy of physics. And I was told you’re smart enough to do philosophy of physics, why are you messing around with biology? And I said, you don’t even understand why biology is interesting, number one, and number two, there’s a lot of work to be done there. And people need to do it, and I’m doing it. As a philosopher of science, I have always been orientated towards addressing problems that scientists have, not so much problems that philosophers have. That is how to do good philosophy of science.
- Robert Lawrence Kuhn
- Pursuing philosophy of science for active scientists, I meet a philosopher working in evolutionary biology, adaptationism, and the mental life of octopuses, Peter Godfrey-Smith.
- Peter Godfrey-Smith
- In my mind, philosophy of biology has two sides that are constantly interacting and talking to each other, and we can understand them by thinking about the nature of philosophy, as a whole. There’s a famous one-line definition of philosophy that was given by Wilfred Sellers. Philosophy is about how things in the broadest possible sense of the term hang together in the broadest possible sense of the term. So, it’s sort of about everything, but about everything in a way that involves taking a step back, further back from the vantage point that you normally see in the sciences. Now, two parts of that everything, the activity of science, the human activity, trying to understand the world scientifically, and also, the living world itself. And in my mind, there’s a part of philosophy of biology which is more about the science, the nature of biological sciences, how the theories work, where the concepts come from, and how they fit together, the nature of our understanding, and there’s a side of the philosophy of biology that has more to do with ourselves, the nature of life. We’re looking at the world through the lens of science rather than looking at the nature of science. There’s a part of philosophy of biology that’s within the philosophy of science, how does science work? How does this part of science work? And there’s a part of philosophy of biology which is in what I call the philosophy of nature, the living part of nature, and how might the biological sciences, as used by a philosopher, help us understand that side?
- Robert Lawrence Kuhn
- Can philosophy of biology provide novel ways of thinking about biology? I ask a philosopher who advocates a “pluralistic metaphysics” of science, John Dupre.
- John Dupre
- I think a good starting point would be not to make too sharp a distinction between philosophy and biology. Then, I think, perhaps, there are two ways in which philosophy of biology can differ from the everyday practice. One of them would be just in the difference between breadth and depth. So, a lot of what philosophers do is trying to draw connections between things that biologists might be talking about, but they don’t necessarily think enough about the way they connect.
- Robert Lawrence Kuhn
- You’ve developed the idea of a metaphysics of biology …
- John Dupre
- My first interest in this came through an interest in essences of things, which is a kind of a negative bit of metaphysics, but it used to be that it was very much an assumption, that things fell into “kinds.” And that these natural “kinds” were natural kinds but that a thing belonged to an actual kind because it had a particular essence, an essential property. But so, one of my first interests, many years ago, was in what was a skeptical interest in this view, and partly coming from actual experience of particularly botany was incredibly difficult to make these distinctions, and everything hybridizes, and of course, everything is evolving all the time. You could see there was nothing in the biology that would make you think there was any such property. And indeed, quite the reverse, the possibility of evolution is largely premised on the fact that there is always indefinite variability within a “kind.”
- Robert Lawrence Kuhn
- Can philosophy of biology be distinguished from philosophy of science? I ask a philosopher known for theoretical perspectives of biology, Paul Griffiths.
- Paul Griffiths
- I think philosophers are always drawn to where the epistemic action is, and if you think about early 20th-century philosophy, the really exciting stuff is coming out of physics. In the second half of the 20th Century, biology just came to take center stage. Molecular biology is such a powerful and successful science but it doesn’t have the key features that we think of as typical of powerful and successful sciences. It doesn’t have a small core of theory that can be expressed in highly general mathematical terms. It doesn’t have, in fact, what a lot of early philosophers of science would have said was necessary to have a theory at all. It’s just a kind of engineering because it doesn’t have the distinctive features that we see in the really powerful sciences like physics and chemistry, and so, that’s a paradox. We’ve got this incredibly powerful and successful science, and it doesn’t fit our basic models in philosophy of science. So, I think those are key reasons why the discipline took off.
- Robert Lawrence Kuhn
- Yet, the claim is that there is indeed a core theory of biology – the gene. I meet the author of the seminal, epoch-defining book, The Selfish Gene, Richard Dawkins. Genetics is digital. It always was, really, since Mendel, but in a rather weaker sense, but Watson-Crick genetics is very, very digital. It’s exactly like computer code, except that it’s quaternary rather than binary, but apart from that, it is computer code, and it’s going from strength to strength. And, in my field of evolution, it’s proving crucial to working out, for example, the family relationships between animals, well, not animals, plants, and bacteria, and everything, because they all have the same genetic code. That’s an astonishing thing. Astonishing.
- Richard Dawkins
- That would have amazed Darwin. What it means is that you can actually literally compare, text for text, the genome of any two living creatures you like, and you can compare bits that are similar. You can count the number of similarities, literally count the number of similarities and differences. And that enables you to trace how long ago they had a common ancestor, calibrated by the fossil record, where you will have certain key landmark points in the fossil record, which you can date. Having calibrated that, you can then use the so-called molecular clock to date all the other points, all the other branch points.
- Robert Lawrence Kuhn
- Yet what happens when there are challenges to current beliefs? I meet philosopher of science and biology, Quayshawn Spencer.
- Quayshawn Spencer
- Thomas Kuhn, a philosopher of science, who wrote Structure of Scientific Revolutions, famously argued that science is structured in these little units called paradigms or research programs that change over time in ways that aren’t as cleanly connected as we previously thought. We make huge jumps, shifts from one way of doing science to another. That can be problematic for thinking about science as this cohesive, continually cumulative knowledge-generating project. So, in that book, he famously and I think rightly, argues that scientists are doing philosophy at certain points in the scientific project. Namely, when they’re building up a new paradigm or research program, there’s certain elements of that, like metaphysical principles, which could be things like definitions of terms. So, think about when scientists came up with research programs like phylogenetic systematics, or evolutionary systematics and numerical taxonomy, they had to define key terms, monophyletic group, species, higher taxa. That’s philosophy, right? Look at research from philosophers that have already been wrestling with these issues. There is already, for example, a long, ongoing debate about the right way to classify things, natural kind theory, even specifically, the right way to define species in philosophy of biology. So, why not tap into that literature and engage?
- Robert Lawrence Kuhn
- But, is a new paradigm shift in biology still possible? I meet the acclaimed heart physiologist with iconoclastic views of systems biology, Denis Noble.
- Denis Noble
- Who could possibly have checked, or have any problems with the idea that we should explore the logic of what we observe, and what we think about what we observe, and how we interpret it? That is what philosophy is. It is the logic of the way you put things together. And I really cannot understand why people should have any problem with that. We take logic as used in mathematics, and we apply it endlessly to biology now. Logic, in a philosophical sense, is much the same. It’s asking the question what is consistent with what we observe? Now, we might get that wrong. There may be many things that are consistent with what we observe, and what we choose amongst the possible consistencies, is a matter of discussion, and also, for future research. But what generates that future research are the ideas that say, well, out of these possibilities, can we distinguish between these? I’m Popperian, you see. The attempt to refute the hypotheses but that’s how science advances. We have an idea that this set of observations in our science may be consistent with this interpretation. But is there another way in which we can test whether that is true? That’s what I’m doing all the time. That’s my subject. That is physiology, which is the physio of logos, which is the logic of life. And I think that’s biological philosophy.
- Robert Lawrence Kuhn
- What about the kinds of questions that philosophy of biology can address? Biological questions? Philosophical questions? I ask a philosopher of biology who focuses on evolutionary theory, Samir Okasha.
- Samir Okasha
- I think of what we do in philosophy of biology as two-fold, really. On the one hand, we look at philosophical questions that arise within biological sciences. So, for example, within evolutionary biology, within molecular biology. So, a good example there, might be the species problem which asks what a species is? Or the question of why one uses functional language in biology? Why do we talk about the function of some organismic attributes? We don’t talk about the function of a river, or a glacier, so why do we talk that way in biology? On the other hand, we have the bearing of biology on traditional matters that philosophers care about. And a good example here might be the problem of free will. New developments in neurobiology, for example, immediately bear on that question of free will. So, that’s an example of the influence going the other way, if you like, from the biology to the philosophy. As for how philosophy of biology relates to the rest of philosophy, I think its reception is largely been a positive one, in the most philosophers, particularly those of a naturalistic persuasion, are on board with the idea that an integration of philosophy, with the natural sciences, is possible. Questions, in ethics, and political philosophy. Questions in metaphysics, and many other areas of philosophy, as well. So, philosophy of biology has a broad appeal.
- Robert Lawrence Kuhn
- Are there laws or regularities in biology, as there are in physics? I meet a philosopher of biology with two PhDs – in Philosophy, and in Biology, Massimo Pigliucci.
- Massimo Pigliucci
- For a long time, biologists themselves have suffered from a sort of an inferiority complex, and it’s like well, if physics is the queen of science, then we ought to try to work like physics. In fact, one of the most influential theoretical biologists of all time, Ronald Fisher, explicitly modeled his approach to population and quantitative genetics on the second principle of thermodynamics. Because he thought that you know, if physicists do it that way, then we have to do it that way. But it turns out, biology, surprise, surprise, it’s a different kind of science. It is concerned with different kinds of objects, and it works differently. It doesn’t work less well or better than physics, it just works differently. And we should appreciate that difference. For instance, biology is, by and large, an historical discipline. That is, we’re not just doing experiments with current living organisms and look at what’s happening now. We are concerned with the entire history of those living organisms. And in fact, the results of our experiments, and therefore, the way in which our experiments inform our theory, are very much dependent on the history of those living organisms, right?
- Robert Lawrence Kuhn
- You have the constraint of the physical environment in which the fetus develops.
- Rachell Powell
- Right. So, in the early stages of animal evolution, you had this, like, parade of bizarre forms, right? And the problem was that in the early stages of animal evolution, you had this great pliability because the developmental process, in this cascade of development that starts with the embryo, and then cascades through differentiation to these more fine-grained organs, and organ systems, and traits, hadn’t been fully laid down yet. And once they are, trying to change the fundamental framework that you’re dealing with, would require changing the early-acting genes in development. And that almost always is going to have catastrophic consequences for the phenotype. So, as a result, once you sort of connected up these so-called upstream components of the developmental process, with all of these downstream batteries of genes that guide differentiation of organs, and organ systems, and so forth, that once you have that, it becomes essentially impossible for selection to then go back and start from the beginning. And so, what you have is a bunch of extinction events that then just whittled away what, you know, the existing breadth of animal forms, and the ones that are remaining, are forever sort of confined to the developmental constraints of their own body plan. Some people have argued that convergent evolution, the independent origination of similar forms and functions is an argument that, in fact, if you rewind the tape of life and play it again, you’re going to get similar –
- Robert Lawrence Kuhn
- It will look similar.
- Rachell Powell
- Similar outcomes, right? But in fact, you know, if you look at this big data set of convergence, many of those convergences look like they are the result of shared developmental constraints that are essentially channeling the adaptive evolution of form in particular directions.
- Robert Lawrence Kuhn
- Are there no generalizations?
- Massimo Pigliucci
- There are no generalizations, right? There are no laws in biology. There are only empirical approximations, and empirical regularities. That once you get history into the mix, things get very different.
- Robert Lawrence Kuhn
- That’s the backdrop for everything.
- Massimo Pigliucci
- Correct. That is a backdrop for everything.
- Robert Lawrence Kuhn
- While biology surely differs from physics, is biology itself pretty much] all the same? I ask a philosopher of biology who focuses on evolutionary innovation and novelty, Alan Love.
- Alan Love
- For me, one of the things that was most fascinating was the difference between different biological disciplines. I was trained in molecular biology. And when I came into the space of biologists working say in ecology and evolution and even larger time scales like paleontology, I was fascinated by the differences that they exhibited, that, yes, they were both scientists, but boy did they think differently, and how come, and could I figure that out? So, first off, it has to do with the relevance of how much theory to how much experiment. So, many areas of biology do quite well without explicit overarching theoretical structures. How can they do that?
- Robert Lawrence Kuhn
- What’s the landscape of biological issues that philosophy of biology can address? I ask a philosopher of science, a pioneer in the field, Philip Kitcher.
- Phillip Kitcher
- I think it’s very important for philosophers of biology to take up controversial issues in the life sciences themselves that are somehow being clouded or being frustrated by the presence of unclarities like the role of evolution in human behavior, for example.
- Robert Lawrence Kuhn
- What’s the landscape of major issues in biology to which philosophers of biology can make a real contribution?
- Phillip Kitcher
- A lot of issues about evolutionary biology that actually dominated thinking about biology among philosophers in the early phases. But more recently, there’s been a healthy interest in issues about genetics, trying to clarify the notion of the gene, for example, about the relationship between biology and the physical sciences, biochemistry, molecular biology, and so forth. Developmental biology and trying to understand and explain the significance of biological discoveries for a broader audience.
- Robert Lawrence Kuhn
- And so …Life begins. What extraordinary contributors! What insightful ideas! Contemporary biology elicits philosophical problems. Great debate about units or levels of selection. Addressing problems that scientists have, not philosophers. Philosophy of biology has two sides: the process of science and the content of biology. The metaphysics of biology. Epistemic action is in biology, yet no core theory. Molecular biology is digital & powerful, tracing evolutionary relatedness. Clarity in programs, such as ‘phylogenic systemics’ or ‘natural kinds’. The power of logic and falsifying hypotheses. What is a “species”? Why “functional language” in biology? Biology is also a historical discipline; there are no laws in biology. Sharp differences among biological disciplines, such as timescales. The landscape of biological issues. Take up controversial issues. I’m thrilled to begin our new pillar of Life, which we need to get …. Closer To Truth. For complete interviews and for further information, please visit closertotruth.com