Does nature have a purpose? The simple scientific answer is no, but the story is, of course, more complicated than that. Concepts like goal, directedness, directionality, and even purpose are used in biology all the time. How can we reconcile these two realities? Today's guest on the HPS podcast is Professor Alan C. Love. Alan is professor of philosophy at the University of Minnesota and director of the Minnesota Centre for Philosophy of Science, where his research focuses on conceptual issues in biology. I met Alan at the integrated HPS conference in March this year, where he presented a fabulous poster on the conceptual muddle surrounding the term telos. Today we'll be discussing a related topic, the concept of purpose in biology. So, hi Alan. Thank you for joining me today. I'm so pleased to have you on the podcast.
Alan C. Love (01:01):
Thank you for having me.
Samara Greenwood (01:02):
You're welcome. Before discussing the concept of the day, I first wanted to ask you, how did you come to history and philosophy of science?
Alan C. Love (01:11):
So, my path to history and philosophy of science was zigzag like it is for many people. I started out in molecular biology and was focused on the possibility of a lab science career, but became a little disillusioned as an undergraduate. I was bumping into philosophy classes, but at the same time not really bumping into philosophy of science classes. It really took a professor to point out the possibility of philosophy of biology that made me think, oh wait, there's an area of philosophy that connects to biology. Then, for graduate school I applied to a bunch of places, but ended up deciding to go to the history and philosophy of science department at the University of Pittsburgh. Arguably my experience was transformed because I had not had any history prior to going into that graduate programme. I really experienced a kind of full immersion in HPS as a graduate student, because even my philosophy classes that I had taken were primarily not philosophy of science. So I was drinking from the fire hose, for sure.
Samara Greenwood (02:33):
<Laughter>. And so how did history add to your understanding of HPS?
Alan C. Love (02:40):
I think history really gave depth perspective on concepts and practises that scientists engage in. Looking back and seeing that small decisions or key decisions at some past juncture really make a difference for the present.
You just can't see those until you look back and examine how we got to the place we are today. That's what HPS as an orientation gave me that I think was different than just a purely philosophy of science orientation.
Samara Greenwood (03:16):
Oh, fabulous. Yes, I can definitely relate. What would you say are now your main interests in HPS?
Alan C. Love (03:23):
A lot of my interests now revolve around what I would broadly call interdisciplinary epistemology. I'm really interested in how scientists with very different backgrounds engage with one another, either fail to communicate or successfully collaborate in common problems that they want to tackle.
Samara Greenwood (03:48):
Turning to the central question, what is the concept today that you're going to be introducing us to that you believe would be of interest to a broader audience?
Alan C. Love (03:57):
So, the concept that I think is really important is teleology, which is a big word that doesn't get used that much these days. It basically refers to the study or focus on purposes. We use purpose in everyday language, but in Greek telos is one of the roots of how we think about the ends or the goals that we aim towards. So teleology broadly refers to that domain of thinking about purposes and in particular, thinking about purposes in nature and trying to understand what that would be like. And that's pretty ancient practice. It goes back to Greek antiquity where some of the first debates occurred.
Samara Greenwood (04:48):
Right. What is it about this particular topic that you think is of interest to a broader audience?
Alan C. Love (04:55):
I think a broader audience doesn't realise maybe just how complicated thinking about purposes in the natural sciences really is. I think that in some science education contexts, students have been told that somehow natural science just doesn't deal with purpose. Therefore you can ignore it. But in fact, many biology students, especially through concepts of function, ask, well, why can't you say that teeth are for grasping prey? That sounds like a purpose to me and what's going on there? I think it's better to surface that and talk about it explicitly than to somehow hide it. That's one of the reasons why I've been leading this big project on thinking about purposes, whether it's related to agency and what it means for an agent have purposes or goal-directed behaviour, or what it means for a biological process to be directed at some outcome and what does it mean for something to be a function or to have a function such as a heart for beating or teeth for grasping prey. All of those are in this space of purpose, particularly in biology. And I think a lot of people are not aware that there's a lot of exciting, interesting things happening, as well as difficult conceptual questions.
Samara Greenwood (06:32):
I suspect some of the difficult conceptual unpacking there is about perhaps appropriate versus inappropriate ideas of purpose in biology. What could you talk about in relation to that?
Alan C. Love (06:44):
Probably the most clear inappropriate use of purpose in biology is a description of the evolutionary process itself as having a goal. Contemporary biology for a long time now has rejected that the evolutionary process itself is aiming towards some outcome. Rather, what we're getting is the the product of causal interactions and various contingent events that yield evolutionary outcomes. So, if somebody was to say well the purpose of the evolutionary process is to produce some trait or some taxon, I think that's where we can clearly say, no, that's not right. That's not a good use of purpose in the natural sciences. However, if we ask the question, are there purposeful behaviours that organisms engage in? I think we can clearly affirm that that's the case. One of my favourites is the broken wing display behaviour in birds where shore birds in particular will oftentimes mimic that they are injured in order to draw predators away from their nest. And it's totally appropriate to talk about the purpose of this behaviour, and the behaviour being there for drawing away predators. That doesn't mean that it's a complete explanation, but the language of purpose is entirely appropriate and is not somehow misleading in the way that it is for describing the evolutionary process.
Samara Greenwood (08:36):
So that leads into a question I had about why you think the terms teleology, telos, and purpose still have that edge of suspicion for use in science today? Is it because there is a conflation perhaps of these two kinds of senses of purpose?
Alan C. Love (08:54):
I think that some of it is a conflation of different senses. There's also this concern about using it in one context and maybe illicitly transferring it to another context. I think also there's a genuine concern about human psychology having a tendency to ascribe purposes, especially to inanimate objects. All those things I think are genuine concerns. They're not things that we should ignore, but they also are not things that, at the end of the day, tell us that you somehow are not able to use the concept of purpose in the sciences anymore. Rather, they're like a label on the package that says, use carefully! Read the instructions! <laughter>
Samara Greenwood (09:45):
That makes a lot of sense. I was interested in extending it a little more. You talked about goal directedness and agency. How do they fit into this picture?
Alan C. Love (09:56):
Well, in thinking about agents - if we, again, think about that broken wing display that the bird is offering to the predator - we want to capture that by saying that the bird is engaged in a behaviour and that behaviour arises from that bird having some kind of agency in the situation, the ability to make choices between different kinds of behaviour that might be displayed. If we're going to say that organisms have the ability to respond differentially in different contexts, one of the things that I think is an interesting question is to then say, well, what's the basis of that? Why is it the case that there can be different responses to similar stimuli? Why is it the case that there can be learning and there can be changes in how they respond to stimuli? And, why is it the case that some organisms have a greater capacity to make fine-grained decisions or choices about what kinds of behaviour they engage in?
(11:21):
We want to somehow capture that in our biology. We want to understand that. So, talking about purpose, we are also talking about agency, because agents are things that have purposes and they make decisions in order to pursue them. I think that a purely mechanical kind of machine-like interpretation of organismal behaviour is, for many biologists at least, not wholly adequate. It isn't to say that it isn't important to recognise the movement of proteins and molecules and other things during organismal behaviour.
But that, in some sense, if we think that everything we need to know about say the broken wing display is somehow contained in a set of gene expression patterns or something like that, we've somehow lost the systemic perspective. And it's that systemic perspective that biologists want to understand about why the bird behaves the way it does in those different circumstances.
I think that what we find, and this is maybe another reason why purpose is an important concept in biology, is it turns out to be intimately linked with these other concepts, with these other ideas that are being used and are also being studied in the biological sciences.
Samara Greenwood (13:00):
Absolutely. And I have an interesting question - from my perspective at least, it is! With this connection between agency and purpose, and they're contributing to each other, is there potential for agency to adjust purpose as well? So different choices may end up shifting that goal directedness to somewhere else. Is there also that return link?
Alan C. Love (13:22):
Yes. Right. You are highlighting that the goal can change over time for the organism, and that is an important thing to study. Under what conditions does an organism decide that they would no longer pursue a particular food or decide to stop attempting to mate?
These are the kinds of things that are highly relevant, but there are also the kinds of questions that are prompted when we're thinking actively about the organism's agency. Its capacity to formulate goals.
It doesn't mean we have to be committed to organisms all having explicit representations of those goals in the same way we might think of ourselves as envisioning, for example, what do I want to get out of my education four years from now?
But we know, especially from a lot of work in contemporary cognitive science that the embodied nature of organisms, including ourselves, means that a lot of the kind of representation of the environment is encoded outside the brain. I think that dovetails nicely with thinking about organisms as systems because we can recognise that embodiment in the bird as much as we can recognise it in ourselves.
Samara Greenwood (15:02): In your research you mention directionality in the life histories of organisms. Can you tell us a little bit more about that?
Alan C. Love (15:12):
So directionality also has this allied connection to purpose, because we typically think of directionality as going in a direction or in an intended direction. Probably the most natural place to highlight directionality would be in an organism's development. When an embryo develops, it doesn't develop willy-nilly, it develops in particular directions. If it is a vertebrate embryo, there is the development of the heart, for example. And the heart is not just any heart, but a heart of the relevant shape and size for the particular organism and the particular species that it's found in. So, when we talk about directionality, we're trying to understand, what does it mean to say that the heart has achieved its morphology, that it is where it's supposed to be? Some of that turns out to be quite complicated because earlier in the 20th century some people would have appealed primarily to a genetic programme to try an account for those sorts of things.
But increasingly, and this is where some of the interdisciplinarity circles back into the conversation, it's the biomedical engineers looking at some of the physics of development that helps us understand that the outcome is conditioned by physical interactions of the materials and the structures that are not encoded in the genome in the way that might have been assumed 50, 60 years ago. So directionality is again, a phenomenon of interest to biologists. How does that happen? How is it so reliable? What are the conditions that mean that this is occurring over and over again in different generations? At the same time, of course, it also is of interest in medicine because we are interested in how things go wrong. We're interested in, why did this person's heart have a malformation of this particular valve? We talk about it as a malformation, in part because we have an expectation that there's a direction heart development should go, and this didn't go in that way. I think that's another important connection, which is that medicine relies on a notion of directionality to capture pathology and departures from standard directionality.
Samara Greenwood (18:12):
Absolutely. And talking about interdisciplinarity, when you work in these interdisciplinary teams, what is the role of the philosopher of science in your experience?
Alan C. Love (18:24):
That's a really good question, and I think it's variable. I don't think it's always the same, but I do think there are a couple things that oftentimes happen.
One is that philosophers, by virtue of being outside of the community, oftentimes make observations that people inside the community simply don't pick up on because it's the water they swim in, so they don't notice it.
Oftentimes I see a role for philosophers making an observation and saying, why is this the way it is? Why are you saying that? Why are you framing it this way? Why are you trying to fit it within this framework?
A second thing that I think philosophers oftentimes do is be clear about, what do you mean by that word? Why did you choose that word rather than another word? Sometimes those choices turn out to be inconsequential, but sometimes they turn out to be really important. Again, they are things that may be missed or not emphasised in some biological or other scientific discourses. Probably more importantly, when you're working interdisciplinarily, the same term can have different meanings in two different communities. Then the philosopher can sometimes be a mediator, a translator, somebody who recognises - this term is being used in different ways - and we can actually figure out how to talk together. But we have to bring all of that out into the open and not simply presume that everybody knows how everybody is speaking.
Samara Greenwood (20:04):
I can imagine there is a lot of miscommunication otherwise. And so by bringing it out, it really helps.
Alan C. Love (20:11):
Especially across disciplinary lines. There's a lot of miscommunication.
Samara Greenwood (20:14):
Is there a particular example you can think of that coming up in your own work?
Alan C. Love (20:18):
Right now, I'm actually working on one that is really not talked about as much by biologists, which is: What is a trait? So biologists talk about, 'I work on this trait and this organism', but what they mean by traits could be everything from a morphological part to a physiological process to a particular measurement. The trait is the average temperature that this organism exhibits in the winter or something like that. Well, what counts as a trait and how should we carve up the organism, so to speak at joints? This is a problem that's been around, again, since antiquity in thinking about how to understand the parts and the traits of organisms. But because of the disciplinary fragmentation today, we can actually have people talking past one another in particular ways. So just one short example in the developmental genetics literature. Some authors have started talking about characters as having mechanisms underneath them, and then character states, which are particular kinds of variations of those characters. If you move over to systematics, where they're trying to reconstruct relationships between different taxa, they also talk about characters and character states, but in fact, what counts as a character in systematics in many cases, counts as a character state for those developmental oriented biologists. So there you have a tremendous possibility for simply talking past one another.
Samara Greenwood (22:09):
<Laughter> What a good example. I was also interested in what kinds of questions are you most interested in examining further?
Alan C. Love (22:17):
I think for my own part, the things that I'm most excited in pursuing are new collaborative relationships with scientists who have yet to maybe think about their frameworks and their concepts as actively.
Right now one of the places where I'm excited to work is in the space between biomedical engineering and developmental biology, related to this directionality that we were discussing before.
Those biomedical engineers have experienced a kind of frustration in being able to talk to developmental geneticists who live in departments separate from the engineering department on their same university campus.
How can those communities be brought into more productive conversation? They're both interested in trying to understand very similar things about how does the embryo directionally develop to get certain outcomes and particularly also outcomes that are medically relevant. Yet they have trouble talking to one another and sometimes talk past one another.
For my part, I'm always interested in - how can that better be facilitated? Under what conditions can that happen?
That's what's exciting about this new big project surrounding purpose. We've tried to set up some novel configurations of philosophers, theoretical biologists, experimental biologists, to be in conversations with one another, to recognise those times when they're actually experiencing friction and not able to talk to one another, but make it a part of the method, make it a part of the method that people are basically not able to be too comfortable in their own conceptual frameworks.
That is a potential way of restructuring scientific inquiry in such a way that we might really make some key advances on understanding the natural phenomena that we wouldn't have otherwise made. And that gets me excited.
Samara Greenwood (24:58):
That sounds very exciting. I can see that being uncomfortable can be a place of potential growth and further inquiry. Going back to a more general question, why do you feel understanding the concept of purpose in science is important more broadly?
Alan C. Love (25:13):
I think the public has some real potential benefits that can emerge when they are recognising that purpose continues to be a relevant scientific concept. And one of these is in simply trying to map it onto our everyday sense of purpose. Sometimes people walk away from the sciences and they say, well, the sciences tell me that, you know, I have no purpose. So I have to somehow create it whole cloth independently of what the sciences say. But in fact, what it means for the sciences to talk about purpose, as we've discussed, is nuanced and subtle and in many ways relevant to how we think about our own purposes and what we want to do, what we can accomplish, how society might be structured. We really need to be careful that we don't either ignore the science that might be relevant to those everyday questions or use the science inappropriately in trying to address those everyday questions.
Both of those dangers, I think, can be avoided, but they're best avoided by actually having an explicit conversation about purpose.
It seems like the tendency for people to err on one side or the other oftentimes is because they think, well, if I can't talk about purpose then this is something that the sciences just can't talk about, or this particular science tells me everything I need to know about who I am, a particular area of genomics, for example. If it tells me about what my genes are, that tells me everything I need to know about my future. So I'm going to have my genome sequenced by 23andme, and that'll tell me how to live my life. Of course, that's a mistake also. So I think by avoiding suppression of the conversation the general public can actually move to a richer and more grounded understanding of what kind of answers the sciences deliver and how they might be relevant for everyday life.
Samara Greenwood (27:48):
That is absolutely fabulous, Alan. I think that's a really excellent point to finish the podcast. Thank you again for joining us on our first season, and it's absolutely been a pleasure to talk with you today.
Alan C. Love (28:01):
Thank you so much, Samara. I really enjoyed it.
Samara Greenwood (28:04):
Thank you for listening to the first season of the HPS podcast, where we discuss all things history, philosophy, and social studies of science. To learn more, check out our website at www.hpsunimelb.org. There you can also find links to our blog, Twitter, Facebook, and Insta, as well as show notes for today's topic. I'm Samara Greenwood, and my co-producer is Indigo Keel. We look forward to having you back again next time.