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Thinking While Walking with Martin Bunzl

Overview & Shownotes

The philosopher Martin Bunzl and he loves living near the Pacific Crest Trail because it allow him to explore nature. The famous foot path also inspired him to embark on a new project of thinking while walking. For him, this spectacular setting proved to be fertile ground for reflecting on philosophical puzzles and questions about nature and ethics.

For the episode transcript, download a copy or read it below.

Contact us at examiningethics@gmail.com

Links to people and ideas mentioned in the show

  1. Martin Bunzl, Thinking While Walking: Reflections on the Pacific Crest Trail
  2. Lyndon B. Johnson, Remarks Upon Signing Four Bills Relating to Conservation and Outdoor Recreation
  3. Pacific Crest Trail
  4. Immanuel Kant and deontology
  5. John Stuart Mill and utilitarianism
  6. Positive and negative duties
  7. Jonathan Haidt and the psychology behind morality


Thanks to Evelyn Brosius for our logo. Music featured in the show:

Insatiable Toad by Blue Dot Sessions

Game Hens by Blue Dot Sessions


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Thinking While Walking with Martin Bunzl

[music: Blue Dot Sessions, Insatiable Toad]

Christiane Wisehart, host and producer: I’m Christiane Wisehart. And this is Examining Ethics, brought to you by The Janet Prindle Institute for Ethics and DePauw University.

Nature has always fascinated the philosopher Martin Bunzl. So when he retired to California, he was excited to live near the Pacific Crest Trail. The close proximity of the famous trail inspired him to embark on a new project of thinking while walking. For him, this spectacular setting proved to be fertile ground for reflecting on philosophical puzzles and questions about nature and ethics.

Martin Bunzl: When I’m walking there I’m thinking about restoration. Trying to correct what we’ve done. The question is, “What happens if, in the course of correcting what you’ve done, the only way to correct it is to do harm?”

Christiane: Stay tuned for my interview with Martin Bunzl on today’s episode of Examining Ethics.

[music fades out]

President Lyndon Johnson: The simplest pleasures and healthful exercise of walking in a natural setting have been almost impossible for the millions of Americans who live in the cities. And where natural areas exist within the cities they’re usually not connected by walkways, and in many cities they are simply just no footpaths that lead out of the city into the countryside. Our history of wise management of America’s national forests has assisted us in designating the initial elements of the National Trail System. Two National Scenic Trails–one in the east and one in the West–are being set aside as the first components of the trail system: the Appalachian Trail and the Pacific Crest Trail. The legislation also calls for study…

[clip fades out]

Christiane: President Johnson designated the PCT a National Trail in 1968. Each year, thousands of visitors hike all or parts of the 2,650 miles between the Canadian and Mexican borders. Every person visiting the trail has their own reasons for doing so, whether it’s to explore personal problems or just take in the scenery. Martin Bunzl had a unique aim in mind when he started walking parts of the PCT. He wanted to use various points in the trail to think through some of the most puzzling philosophical questions related to nature. The result was his book Thinking While Walking. I spoke with him recently about just a few of the many subjects he explores in it.
[interview begins]
Christiane: So what gave you the idea for this book?
Martin Bunzl: I had been thinking about an interest in nature, writ large, which came out of work I’ve been doing since 2008 on the intersection of philosophy and climate change. And at the same time, as a newly retired person with time on my hands, I was aware that this magnificent trail, 2,600 plus miles, starts 50 miles from my house in Campo, California on the Mexico border, and goes all the way up to Manning in Canada.

And I’ve also had a love affair with strolling and thinking while I stroll. Some of my most creative insights (to the extent I have had any) in philosophy, come from that particular state of mind when you’re not thinking too hard. You’re mildly distracted and your mind wanders. And so I thought this might be a creative exercise. I went to different sections on the Pacific Crest Trail, and some I had something specific in mind. And some I just started walking and thinking.

Christiane: I wonder, is there anything about being in nature, walking in nature, hiking in nature, that makes one more inclined to be philosophically inquisitive? Or could you have done this project from the parking lot?
Martin Bunzl: Well, that’s an interesting thought. I did find, when I lived on the East Coast, that driving was sometimes a catalyst for philosophical thought. But, if you’re interested in nature, and thinking about nature, it’s good to be in nature, because you get a greater chance that something around you will trigger a thought that you hadn’t had before. This trail is so astonishing. It’s not astonishing in the way that people think. I mean you’re walking on this small path for thousands of miles. And in one sense, it’s very much the same, if you look down at your feet. But the surroundings vary an enormous amount. And so, yeah I think it’s a good catalyst for thinking about nature to be in nature.
Christiane: So I thought maybe we could sort of talk about the interesting questions that you came up with. And you can sort of set the scene for us in terms of the space that inspired these questions. So my first question comes from the Mojave Desert. You’re talking a lot about the lifeboat scenario, and climate change. You write that, “Considerations of welfare override considerations of justice when it comes to climate change.” I just wondered if you can expand on that? I thought that was..that was really challenging for me.

Martin Bunzl: The Pacific Crest Trail goes through the Western edge of the Mojave Desert. I think when people think, “Well I’m walking in a desert,” you have a picture of walking across the Sahara Desert–this vast expanse of sand dunes. But the Mojave Desert is not that way. The chapter starts with me walking down a narrow road and coming to an aqueduct that’s a canal that is delivering water to Los Angeles. And then looking up and seeing one of the largest wind farms in the United States on the hill overlooking it. And then looking to my right and seeing one of the largest solar farms in the United States. I think this is emblematic of parts of the Pacific Crest Trail. It’s not as natural and wild as people like to fantasize. Humans have intruded on it with its technology. And in fact that arena of the Mojave Desert has been very affected by human beings, over farming it, draining the water table, and pretty much transforming it.

The setting is one in which I do start thinking about ethical questions, which I do at different stages. One of the things that I’m interested in is this counterpoint between what philosophers call deontological thinking versus consequentialist thinking. Thinking in the style that Kant thinks versus thinking in the way that John Stuart Mill thinks. Kant really speaks about never looking to the consequences of an act to decide on its rightness or wrongness. While Mill defends the proposition that we should do so.

But in introductions to philosophy, or a basic ethics, we often treat these as two competing theories of right and wrong. And in the course of this book, I’ve come to think that that’s a wrong way to think about it. I think that deontological thinking starts from the bottom up, from thinking about right and wrong from an individual point of view. I think John Stuart Mill’s kind of theory, a theory of consequentialism, is really a social theory. It’s a theory of the general good. I think that the attempt to try and merge these two into some overriding unified moral theory, starts with a misconception that they’re both theories about the individual.

I think they are theories about different subjects. But we’re nonetheless still faced with the choice, when do you allow considerations of the general good, considerations of social welfare to trump considerations of notions of the individual right? When I was teaching philosophy at the introductory level, I’d always give my students one of these examples. It’s a classic lifeboat example. There are five people in the lifeboat. There’s no food. What should you do? One of the people has to get thrown overboard. For an undergraduate student, normally say one of them has to get eaten. So the question is, “Who gets eaten? How do you make a decision?” And most people will start off as I think, Kantians. They’ll say, “The fair thing to do is draw straws. Give everyone a chance.”

And then in this class, what you do is, you start boosting the contribution that one of these people can make to society. They’re going to solve AIDS, or solve COVID, or they’re going to save climate change. They’re going to save the world. And eventually, you can get every kid in the class to flip from considerations of justice, to considerations of welfare, except maybe one holdout, who will say, “Let seven million people die. I respect the rights of the one.” But nearly everyone has a tipping point, as it were.

And so I’m interested in what, to put it provocatively might be called the limits of justice in the interest of welfare. And I don’t think we think enough about that.
Christiane: And how does that play out with regard to climate change?

Martin Bunzl: Well, I think with climate change, we focus, and this is very cruel, but I’m willing to defend it. I think we focus too much on the number of people who will suffer because of climate change. And that blinds us to some really complicated issues that affect the vast majority of people in the world. If we look at the world today, there are about 7.8 billion people, and 6.5 billion of those people are poor. They live very poor lives. When we think about climate change and their interests, we tend to focus on the small number, it’s a few million people, who will be really dramatically adversely affected by climate change. And from that, we’ve embraced the rhetoric that the poor of the world are going to be suffering the most from climate change.

But the vast majority of poor people, from those two million, up to the really rich remaining 1.5 billion people, have a much more complicated situation than that. And the reason I say that is the following: if we look at the challenge of climate change in realistic terms, it’s going to take a half a century, or 75 years, to fully convert to a renewable portfolio, to give up all fossil fuels. If you take the 6.5 poor people in the world, they aspire to a better life. They aspire to refrigerators that we have. They aspire to an electric bike. That energy cannot be satisfied fully by renewable energy now. The renewable portfolio of the world is about 20%, and that includes nuclear fuel. And energy demand is going to grow by about 40% over the next 30 years. And the vast majority of that demand is from the developing world. There’s no way we energy hogs in the developed world can cut back and make a significant difference to those people in the world.

I think from the point of view of welfare of the vast majority of poor people in the world, there is actually a trade-off between how many people will suffer from climate change, dramatically, if you live in Bangladesh and you’re at sea level, versus what is going to happen? What’s in the interest of the majority of those poor people? I think these are very complicated trade-offs. Our discussion about them is colored by the fact that we often come to these debates with unrealistic ideas about what can be done. You can’t snap your fingers and have a fully renewable energy portfolio in five or ten years and satisfy the needs of these billions of people.

Christiane: The next stop on our hike is Castella. I’m going to steal a question from you, which is, is it permissible to do harm, even if you have a view to do good?
Martin Bunzl: Yeah. Castella is an astonishing place. When you go into the State Park in Castella, you see some immensely old rock formations, hundreds of millions of years old. But Castella is another sad place in the sense that, if you’re an ignoramus about nature as I am, you think, “Oh, I’m in a forest.” But it’s not first growth forest. It’s a forest that was regrown after the first forests were destroyed by white settlers. White settlers came in there because they were looking for gold, initially. The search for the gold led to a lot of killing of the native people there. And then the digging for gold gave rise to a lot of pollution, which killed off a lot of the indigenous animals in the area.

I think about that area because, in that chapter, when I’m walking there I’m thinking about restoration. Trying to correct what we’ve done. The question is, “What happens if, in the course of correcting what you’ve done, the only way to correct it is to do harm?” In a way, this takes us back to the discussion of welfarist considerations, because if you’re a welfarist, you allow that sometimes you may need to do harm in order to do good. And I think in the present situation, we are in a situation where we face such choices. If we’re discussing it as you’ve taken the question, we’re assuming that we’re doing harm to things that are rights-bearers, that have moral standing.

What are we to do? Well we’re on a course, now, to cause the extinction of 80% of species in the world. If we want to cut that back, we have to intervene in drastic ways. One of the ways we can intervene is to lime the ocean to decrease the amount of carbon dioxide the ocean gives out to the atmosphere and to increase the capacity of the ocean to absorb carbon dioxide from the atmosphere. One of the ways to do that is an area that’s known as ocean upwelling, which runs all the way up and down the West Coast of the United States. Because when ocean upwelling takes place, cold air from deep in the ocean rises up. And as it rises up, like a bottle of soda being the cap taken off it, carbon dioxide is held under pressure, and that cold water as it rises up, is released into the atmosphere.

Now, if you lime that section of the ocean, you can reduce the amount of carbon dioxide being released. And that would have a salutory effect on global warming if it was done on scale. But the areas of ocean upwelling are ocean nurseries, where species are spawning and growing offspring. By engaging in a strong amount of liming the ocean, you’re going to change the acidity quite quickly, in a way that will make it impossible for the species to adjust. You may, in fact, cause the extinction of those species, or damage them greatly. And the question is, is that admissible if, in the process, you’re going to save a lot of other species?

I think we face some very, very difficult choices. And this touches on, I think, a philosophical blind spot that a lot of people have ethically. They think that acting is different from not acting, that if you don’t act, you’re on safer ground than if you act. So if by not acting, something bad happens, that’s somehow is better off than acting and something bad happened. This touches on an even larger question in ethics, which you may have discussed with your listeners, which is the difference between positive and negative duties.

Christiane Wisehart: Yeah. Can you expand on positive and negative duties a little bit?
Martin Bunzl: Philosophers have been very good in developing a theory of negative ethics … of negative duties. That is a duty to do no harm. So we have a principle that it’s wrong for me to interfere with you, and it’s wrong for you to interfere with me. I shouldn’t interfere with your freedom of movement, your freedom of speech, and so too, you with me. And when you try and ground this kind of sentiment of negative ethics, you can see how it’s in all of our self interest. When human beings lived on their own, isolated, we didn’t worry about this. As we came together for mutual benefit and started to live cheek by jowl, we could step on each others’ toes, as it were, and it became in all of our self interests to try and minimize the interference with others.

But philosophers are very bad in generating a theory of positive duty, that I have a duty to do something. Example you might think of is, I have a duty not to drown a child that I see on the beach. But philosophers usually have been hard nosed about the fact that I don’t have a duty to save a drowning child. It’s maybe condemnable to me, but I don’t do moral wrong by doing that. I have no duty to do that.

Now the challenge for ethics, I think, is how you generate a theory of positive duties. It’s easy for a consequentialist or a welfarist, but it’s very, very hard for someone who believes that moral theory consists of a theory of justice, and a theory of justice grounded on a Kantian kind of mode of thinking. That is, adopt only a principle that you can will to be a universal rule, consistently. I think a lot of what I’m worried about in this book has to do with collective action that I want to ground on considerations of duty. And if I don’t want to be, which I don’t, a sort of full throated, full-time consequentialist, I think that’s a real challenge to do.

Christiane: Those issues come up in Stevens Pass, where we’re thinking about what do we owe other living beings…

Martin Bunzl: Well Stevens Pass, which is in the state of Washington, in the middle of the state of Washington, just before you get into the Northern Cascade Mountains, is another example of a shock of the Pacific Crest Trail of far from being wild and untouched by human beings, in that you actually walk through a ski resort. And one of the most disconcerting things is the path takes you underneath the pylons of the cable car. And you look out, and you see how all of this marvelous land has been clear cut to make space for the ski runs and the parking lots, and the cable cars. And the indigenous animals that live there have in a sense been removed, if only because their environment has been changed. That starts me thinking about animal rights. I’m a very hard-nosed, old school kind of guy in that I think that awareness is a condition for having moral standing.

You can’t have moral standing unless there is something like it is to be you and it matters to you, not in the biological sense that it matters to an insect to reproduce, or a virus to reproduce, but in the sense that if you were mistreated as it were, it matters to you. So in this chapter, I spend quite a lot of time discussing the notion of awareness and self awareness, and whether or not it’s plausible to think that most animals have the capacity for awareness. I think about it, primarily on the grounds of our best theory of the kind of hardware we need upstairs in order to have the capacity for awareness.

Of course, it’s very popular to say today that things like octupuses are so different in their structure and behave in such complicated way that maybe they’re aware. The position I want to take is this, and I feel very strongly about this, I don’t think that moral theories, or ethical theories lend themselves to two levels of theory. You either have moral standing, or you don’t have moral standing. And if you have moral standing, then the whole point of ethics is to say you deserve equal standing to everyone else.

It doesn’t work to say, “Well, we’ll give cows moral standing, but there’s sort of second class moral standing.” That’s like saying, “Oh, slaves. Yes, they’re human beings. They have some rights. But they don’t have all of the rights of the real full-fledged moral beings.” It’s a prescription for disaster in terms of how we organize society.

And so when people talk about animal rights, I want them to think really strongly about the implications. I think if you’re going to give animal rights, then they have to have the same rights as you and me. And I don’t think most people will end up doing that. And that leads me to the thought that, maybe moral theory is a purely anthropomorphic and anthropocentric enterprise that we construct to try and regulate treatment between ourselves as a species. But it’s not nearly as easy as people think to extend to other species. I mean, unless they come and talk to you, and you suddenly realize they’re like us. They just look very different.
Christiane: We’re talking about considerations of animal welfare, what we owe other living beings. And you raise a similar set of questions when you’re in the Meadows, which is South of Stevens Pass. And you ask, “Is it permissible to privilege certain species over other species?” for example native species over species that have been introduced into the landscape.

Martin Bunzl: If we’re going to pose it as a question of permissibility, I think that, in a sense, we’re going to be ascribing some moral standing to these species. At least for the purposes of argument in this chapter, I say let’s assume that’s the case, even though later I give up that assumption. But I’m a philosopher, so I get to do whatever I want in that regard. I’m unconstrained by facts.

What I’m intrigued about in this chapter is the way in which we do privilege certain species over others. We delude ourselves into thinking that this is governed by certain kind of high mindedness. But in fact, I think it’s actually an expression of anthropocentric view of nature, so we love mammals and hate cockroaches.

But another thing we do is, we sentimentalize somehow the idea of original or native species, over invasive species. And, I really go sort of full throated here in questioning these very categories. Think of the Hawaiian Islands. They come from volcanoes underground that spew lava and build the island. There’s nothing native there. Everything is an invasive species, because it all arrived by wind, or by bird droppings, or by sea, long before humans came there. So I’m struck by the distinctions that people make in this regard.

But I’m also struck, more importantly from the point of view of our relationship to nature, with the idea that we are driven by an idea of trying to freeze nature in time. Which, of course goes against what to me is the central feature of nature, which is natural selection. And natural selection dooms whatever exists to change over time.

And yet, the Pacific Crest Trail, and Yosemite, and all of the places you go are, in a sense … The conceit behind them is the idea that we can preserve nature as it is. And it’s a very unrealistic notion, whether or not we are causing change of nature through climate change, or just natural processes are doing it. Yosemite is built by John Muir, with the idea that we can represent nature as pure and without man, and unaffected, frozen in time. But, Yosemite has a long history, from the Ice Age, and even today, the people that work at Yosemite are saying because of climate change, there’s no way we can preserve it the way it is.

As I write at different sections of the book, this idea of freezing nature, comes out of a binary opposition between human beings and nature that arises in the face of the Industrial Revolution. The idea that nature is pure and benevolent, and beautiful, and man, human beings are the source of everything evil with regard to nature. I’m struck by the fact that, as I said at the very end of the book, that John Muir expresses this by evicting the native people from Yosemite, because he doesn’t want people to come and see Yosemite and see human beings messing it up. It’s to be frozen as free of man, not with man in it.

Christiane: You said that you didn’t hike the whole Pacific Crest Trail. [crosstalk] But even hiking parts of it are, of course, physically demanding and challenging. But I wanted to know what were some of the most demanding questions that this project brought up for you?

Martin Bunzl: I didn’t even hike. I strolled. I walked. And in fact, I have some rather mean things to say about people who take on this project, because I think it’s a sort of self-centered project. I think the most demanding for me is what I take up in the ninth chapter of the book, which is struggling with the notion of whether we have a duty to nature. And this has preoccupied me for a number of years. I don’t want to romanticize nature and say that nature is a person, or nature has moral standing. But, I want to come up with an argument that we have a duty to nature, a positive duty to nature, not just a duty to do no harm.

I’m walking in the Northern Cascades, which is amazing. I mean it’s one of the most beautiful places I’ve ever been in the world. I’m actually moved to tears when I’m there. I don’t cry that easily. I’m just overwhelmed by the beauty of it. And then I come home and start writing. And I’m plowing through this really turgid, philosophical argument by Rollston on duties to nature, which doesn’t make any sense. And I’m trying to pull out an argument about it. And I suddenly have this epiphany. I say to myself, “Why are you doing this? You want a moral theory of duty to generate a way in which we should relate to nature, respectfully. But when you underwent this emotional epiphany there, you naturally had that feeling of humility and respect of nature. Give up the thinking and embrace the emotion.” Which is an expensive demand on a philosopher, we don’t normally embrace emotional argument. We embrace logical argument.

For me, that was a really creative point, because I started thinking about how being in nature does evoke humility, and how evoking humility can evoke a kind of set of constraints on action that I think are important. I think Peter Railton, the philosopher, wrote about it the first time I saw it, which is talking about it as if we’re thinking less and trying to evoke in people a state of mind which will produce behaviors that we think are important.

And that taps into an even more interesting literature, that Jon Haidt has promoted, in which he argues that a lot of our thinking in the moral domain is in fact an ex-post-facto rationalization for something we’ve arrived at through non-cognitive processes that operate more quickly in the brain.

I’ll give you an example that’s not moral, per se. But, you meet someone and you come to a judgment, ‘I don’t think this person is trustworthy, or I think that person is trustworthy.” He thinks and has evidence he thinks supports it. You’ve already arrived at that conclusion before you think it. You’ve arrived at it through an emotional response to the person, which of course is very bad interracially, because you’re more inclined to have an emotional response of the right kind to people that “like you” versus people “different from you.” And this has to do with, as it were, fast and slow circuits in the brain, when perception goes to emotional centers more quickly than it goes to higher cognitive centers.

I think this is true about ethical thinking as well. And that’s what I learned from this, that maybe in thinking about relationship to nature, it’s less about thinking and more about acting.

[Interview ends]

[music: Blue Dot Sessions, Game Hens]
[sound: birdsong and footfalls on a crunchy walk]

Christiane: Examining Ethics is hosted by The Janet Prindle Institute for Ethics at DePauw University. Christiane Wisehart wrote and produced the show. Our logo was created by Evie Brosius. Production assistance from Brian Price. Our music is by Blue Dot Sessions and can be found online at sessions.blue. Heat rash on my forehead courtesy of an Indiana summer. Examining Ethics is made possible by the generous support of DePauw Alumni, friends of the Prindle Institute, and you the listeners. Thank you for your support. The views expressed here are the opinions of the individual speakers alone. They do not represent the position of DePauw University or the Prindle Institute for Ethics.

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