Transcript

Cold open [00:00:00]

Christian Ruhl: In the last couple of years, the average philanthropic funding in the nuclear space was around $47 million a year — again, these are kind of point estimates; you should imagine uncertainty ranges around each of these — and then recently, the largest funder, the MacArthur Foundation, has withdrawn from the field, leaving this shortfall that brings the total expected amount of money to, say, $32 million a year.

If you look at $32 million a year, that’s basically nothing, right? The budget of Oppenheimer, the movie, was $100 million a year. So there, filmmakers are spending three times as much on a movie about nuclear war as we’re spending on mitigating the risks from such a war.

Luisa’s intro [00:00:57]

Luisa Rodriguez: Hi listeners, this is 80k After Hours. I’m Luisa Rodriguez, one of the hosts of The 80,000 Hours Podcast.

In this episode, I talk with Founders Pledge researcher Christian Ruhl on a topic that’s… well, I won’t say “close to my heart,” but I’ve certainly spent a lot of time thinking about it: nuclear war. Before I joined 80,000 Hours, I was a researcher for Rethink Priorities, where my first-ever research work involved me trying to estimate how bad a nuclear war would be.

It’s been a while since I’ve been fully immersed in that world, so I was super excited to talk to Christian about not only how the risks have changed since I did my own research, but also on what he thinks are underrated approaches to reducing the worst nuclear risks. We talk through questions like:

• How can we ensure deescalation can happen after the usual forms of interstate communication have been knocked out by nuclear war?
• What can we do to increase the odds that a democratic government will maintain control in a postwar civilisation, rather than an authoritarian one?
• How can governments best prepare their citizens to survive nuclear-related devastation?

OK, without further ado, here’s our conversation.

The interview begins [00:02:19]

Luisa Rodriguez: Today I’m speaking with Christian Ruhl. Christian’s a senior researcher at Founders Pledge, where he focuses on the worst risks from great power conflict and weapons of mass destruction, and where he also manages the Global Catastrophic Risks Fund. Thank you so much for coming on the podcast, Christian.

Christian Ruhl: Hi, thanks so much for having me on. It’s great to be here. I should mention for our listeners that I have a stutter. So you’ll hear some pauses and speech patterns throughout the conversation that might seem sort of unusual, but I think we’ll get to that later.

Luisa Rodriguez: Yeah, as a teaser, we actually are going to talk about that quite explicitly later on, about your experience of having a stutter. And I’m personally really looking forward to talking about that with you and hearing what it’s like.

Before we do that, we’re going to talk a bunch about nuclear war. I’m excited to talk about what you call “the nuclear equivalent of mosquito nets,” in terms of nuclear interventions that might be kind of silver bullets, or at least very cost effective.

But first, I’m curious to hear about your take on what some analysts are calling a new nuclear age. So basically, what is changing? What is making people say that we’re in a new nuclear age?

Christian Ruhl: Yeah, thanks for that question. So what are we talking about when we talk about the new nuclear age? I think what we’re talking about at a really high level is the emergence of what people are calling this three-body problem in nuclear war — with the US, Russia, and China now — at the same time that the world seems poised to undergo this revolution, basically, with AI.

The three-body problem [00:04:11]

Luisa Rodriguez: Yeah, those both do seem like very big things. Can you explain this three-body problem thing in a bit more detail?

Christian Ruhl: Yeah. For much of the Cold War, the US and the Soviet Union were the two nuclear superpowers. Other states eventually did acquire nuclear weapons, but in terms of arsenals, those two just towered over all of them. We’re talking orders of magnitude bigger. And that had been the case for a long time, this kind of bipolar order.

After the Cold War, people in many cases kind of stopped paying attention to this altogether. And what’s happened in the last couple of years is that China seems poised to expand its own arsenal. So in 2020, their number of warheads, best estimate, is in the low 200s — 220 or so. Last year, that was up to 400 something. And now we’re talking 500, and the projections suggest it could be as high as 1,000 by 2030 and 1,500 by 2035 — so really this massive increase.

Luisa Rodriguez: Wow. Yeah. In thinking through the significance of this, I remember when I was learning about nuclear war and nuclear weapons a few years ago, I remember kind of concluding for myself that nuclear war between the US and Russia seemed most terrifying, because they had so many warheads between them that you could get this terrible, scary thing called nuclear winter — which theoretically seems only likely to happen when you have thousands of nuclear warheads detonated. So one thing that just sticks out to me immediately is like, agh, there’s another global power that might eventually, potentially have enough warheads to create this kind of catastrophic-type outcome.

Are there other things significant about this, besides just that nuclear wars could be much worse? Well, at least the ones involving China now? For example, things about the kind of game theoretic dynamics of how all of these countries relate to each other?

Christian Ruhl: Yeah, that’s exactly right. Not all nuclear wars would be the same, and the very biggest wars would be by far the worst. So I think what you’ve written in the past is exactly right on the issue.

But yeah, I think there are some structural changes too that happen. So negotiations just become more complex when you have three parties rather than two, and there are issues with targeting when you’re potentially facing two adversaries.

I think it’s helpful to think about this with an analogy. Let’s say you’re an outlaw, and a fellow outlaw has challenged you to a duel. And you’re outside, and the tumbleweed is rolling, and the vultures are flying overhead — it’s a standoff, and we’ve been in that standoff for a while. And suddenly a third person joins, and you don’t know what to do. Are they going to point their gun at you? And that totally changes the structure of the game.

Luisa Rodriguez: Totally, yes. That makes it super visceral for me. I would not like to be in that standoff. That sounds worse. I don’t like it.

Effect of AI [00:07:58]

Luisa Rodriguez: OK, so that’s the three-body problem, and that does seem really important to me. I guess there’s also the way AI might change things. What’s the high-level overview of what that might look like?

Christian Ruhl: I think it’s really challenging to predict the integration of AI and military systems, but we do see that states seem to be really interested in doing this. I think it all depends on how AI is developed and integrated. But the features of the international system might very well pull states towards framing some of this as a race and as a competition — the kind of dynamics that we might worry about with transformative AI too, pushing states towards premature deployment of unsafe technology.

So that’s the high level. We have a report on this too at Founders Pledge, called Autonomous Weapon Systems and Military AI. I’m happy to go into one example of what this might look like too.

Luisa Rodriguez: Yeah, that’d be great.

Christian Ruhl: So I think a lot of people talk about integrating AI into NC3 systems themselves — that’s nuclear command, control, and communications. Fortunately, a lot of states have said we don’t really want to do that.

Luisa Rodriguez: That’s great.

Christian Ruhl: It is, yeah. Of course that might change. But I don’t think you need that to see how AI-enabled warfare changes the risk of nuclear war. You can even just have AI integrated in conventional warfare — where, let’s say, you automate more and more of the process, where AI-enabled weapon systems are just faster. You have AI-enabled ships, support systems, and many things start happening at machine speed, and shaving off some time here and there. The cumulative result of that might look like speeding up the pace of war. In China, they sometimes call this idea “battlefield singularity.” And in the West, it’s sometimes called “hyperwar.”

Luisa Rodriguez: Yeah. Both the terms “battlefield singularity” and “hyperwar” sound terrifying to me, so I don’t love that.

Just to make sure I understand, is the idea that it’s not that AI will necessarily be incorporated into nuclear weapons command, control, and communications; it’s that war in general might become more automated and autonomous, using AI in a bunch of different ways. And then as that happened, just the pace of war could become so much faster in general, that that would just be a scary thing — because as things escalated, and leaders were considering nuclear weapons, everything would be moving at a more rapid pace, and they’d have less time to make potentially nuclear-related decisions. Is that kind of the idea?

Christian Ruhl: Yeah, exactly. I think it’s kind of a subset of the broader point that AI is this general purpose technology. So we might expect it to transform a whole lot of how our world works, and this is a subset of that.

To maybe make this more concrete, there’s this article from Michael Horowitz called “When speed kills,” and that gets at some of the intuitions. One of those could be that, with this increasing speed of war, you’re compressing a two-week crisis into two hours, right?

So imagine the Cuban Missile Crisis playing out much, much faster. So that might not leave time for people like Vasily Arkhipov, this Soviet naval officer who famously helped prevent a nuclear torpedo launch during the crisis. When things happen so fast, there just might not be time for that. So maybe that helps make it more concrete.

Luisa Rodriguez: Yeah, it does. Is it possible either or both of these things could actually make the world safer? Like maybe China having more nuclear weapons increases a broader deterrence. Or maybe AI helps us avoid the kinds of mistakes that humans make, and AI isn’t totally immune to, but might make less than humans — in the same way that AI also kills people in autonomous vehicle crashes, but it does so less than humans, and so it’s still an improvement.

Christian Ruhl: I think both of those are totally possible, and we shouldn’t be too alarmist about any of these. So to totally turn the example on its head, it’s possible that if the speed of war increases, that leaves a longer window for making carefully considered decisions. Or it’s possible having a third nuclear power makes you think twice about starting nuclear war.

Ideally, what we’d want is a vibrant NGO community looking into all this, studying this rigorously. But as I think we’ll get into, there’s unfortunately not much funding for that at the moment. And that’s, I think, the third factor that’s making this time quite scary.

What we have going for us, and not [00:13:32]

Luisa Rodriguez: Yeah. Actually, let’s turn to that. I’m curious how ready we are for this new nuclear age. Maybe let’s just start with what we have going for us. What’s going well?

Christian Ruhl: Yeah, so I think we’re not ready. But what’s going well? I think one of the big things we have going for us is that apparently we’ve been very lucky. If you look at the history of the Cold War, the number of accidents, close calls, near misses, and so on is horrifying. It’s kind of a miracle that we haven’t had a nuclear war yet. And I think this provides a learning opportunity: it teaches us we can’t continue to rely on this good luck.

Luisa Rodriguez: OK, so we’ve had luck on our side, but I guess you’re worried that we won’t indefinitely. But surely there are some things that are better now than they were in the last nuclear eras?

Christian Ruhl: Yeah. I think the really big one that we should be thankful for is if we compare the total world arsenals now to what we had at the height of the Cold War, let’s say 1986: right now, if you add it up, it comes out to just about 10,000. In 1986, we were talking 70,000 or thereabouts. So that’s awesome. That’s great. We’re much safer thanks to that.

Another thing that’s going for us is that the US, one of the biggest nuclear superpowers, has this vibrant civil society and a fairly responsive government, and at least in this space, good ideas and risk-mitigation measures really can make it up to the highest levels. So I think there’s a case for the tractability of policy advocacy here.

Luisa Rodriguez: Cool. OK, yes. That is at least some good stuff. What is not going for us?

Christian Ruhl: I think there’s a really big one that we should talk about, which is this large funding shortfall recently that means there are fewer people potentially working on these big emerging problems that we talked about earlier.

In the last couple of years, the average philanthropic funding in the nuclear space was around $47 million a year — again, these are kind of point estimates; you should imagine uncertainty ranges around each of these — and then recently, the largest funder, the MacArthur Foundation, has withdrawn from the field, leaving this shortfall that brings the total expected amount of money to, say, $32 million a year.

If you look at $32 million a year, that’s basically nothing, right? The budget of Oppenheimer, the movie, was $100 million a year. So there, filmmakers are spending three times as much on a movie about nuclear war as we’re spending on mitigating the risks from such a war.

Luisa Rodriguez: Yeah, that is really surprising and terrifying. I feel like I’m relatively well informed about nuclear issues, and I still had no idea that the funding was that low. So that feels really just alarming.

Christian Ruhl: It’s alarming, but also it’s potentially an opportunity to help guide the field towards some of the most important problems. At this point, even fairly modest amounts of money — at least by the standards of philanthropists who spend billions pushing their preferred policies every year — a few million can actually help us protect ourselves from the most extreme kinds of risks.

Luisa Rodriguez: Yeah. That’s a nice reframe of a thing that is, mostly I think, pretty scary: as an opportunity for people to use donations to do more good than they might in a field that’s less neglected right now.

Right-of-boom interventions [00:17:50]

Luisa Rodriguez: OK, let’s talk about potential interventions then. My impression is that most of the work in the nuclear space is on nonproliferation and nuclear disarmament and deterrence — so mostly things that aim to reduce the odds that a nuclear war ever starts. But you’re particularly interested in nuclear-related interventions that are helpful in scenarios where nuclear bombs have already been detonated. You call these “right-of-boom interventions.” Can you explain the distinction between right-of-boom interventions and left-of-boom ones?

Christian Ruhl: Yeah. So the big motivation here is: what is the high-impact thing to do here? And I understand that “high-impact” is a very unfortunate phrase to use when we’re talking about bombs going off.

I’m going to make an analogy to car crashes. So for car crashes, we can maybe think about dividing interventions into left-of-crash and right-of-crash interventions, where left-of-crash includes things like rules of the road, stop signs, traffic lights, driver’s licences, and so on. And we also have right-of-crash interventions in case the first layer of defence fails — so we’re talking seatbelts, airbags, features of a car to make it safer, ambulances, hospitals. Why do we have this? Because we know that there are many reasons that cars crash and accidents happen.

So we can take that back to nuclear war. We really, really want to make sure that nuclear war never breaks out. But we also know — from all of the examples of the Cold War, all these close calls — that it very well could, as long as there are nuclear weapons in the world. So if it does, we want to have some ways of preventing that from turning into a civilisation-threatening, cataclysmic kind of war that you’ve thought about in your own work. And those kinds of interventions — war limitation, intrawar escalation management, civil defence — those are kind of the seatbelts and airbags of the nuclear world. So to borrow a phrase from one of my colleagues, right-of-boom is a class of interventions for when “shit hits the fan.”

And before we go on, just to be clear, I think we shouldn’t lose sight of, with nuclear war, we’re really talking about the mass murder of civilians on an almost unimaginable scale. So I’m talking about it in terms of limiting the damage to human civilisation if a war does break out in the rest of this conversation. That’s in no way meant to legitimise the use or even possession of nuclear weapons, or to encourage nuclear war fighting. Rather, given the realities of this world — we’re a fairly violent species of ape; we’ve built this civilisation that somehow got its hands on these weapons — what can we do to minimise the horrible suffering that will occur if these weapons are ever used?

Luisa Rodriguez: Yeah, totally. I remember when I was doing research on this topic, I’d catch myself saying things that were absolutely awful, like, “…would only cause 500 million deaths.”

Christian Ruhl: Right. “It’s a small nuclear war.”

Luisa Rodriguez: Yeah, right. When a small nuclear war is still truly one of the most horrific things I can imagine.

Christian Ruhl: Exactly.

Luisa Rodriguez: There are more horrific things, but that doesn’t mean that a so-called “small” nuclear war or a nuclear war that doesn’t kill everyone is anything but too horrible for words. So yes, I appreciate that caveat. Are there other reasons that we should be dedicating more resources to right-of-boom interventions?

Christian Ruhl: Yeah. Basically, the logic here is we should have a layered defence against catastrophic risks. There’s this great article, I think from 2020, called “Defence in depth against human extinction.” So imagine you live in a world, again, with cars — but no seatbelts, no airbags, or any other safety features. That’s the world we live in right now when it comes to nuclear war. And fundamentally, that’s why I think we should be dedicating more resources to right-of-boom interventions.

So that’s the general idea, but it’s also, as you suggest, a subtler argument about philanthropic strategy here, and about making allocations in philanthropy under high uncertainty. So fundamentally, this is about taking not just one step back but like 10 steps back, and thinking about the structure of the problem at a really high level, to kind of figure out the most effective ways to do good at the margins.

So we know a few things about nuclear war. First of all, not all nuclear wars are created equal. There’s a qualitative difference between a single weapon going off, and the superpowers unleashing their full arsenals. One of those is, as you said, a truly horrific humanitarian disaster, but it’s mostly local. And the other one is this unprecedented global cataclysm that might well threaten modern civilisation itself.

So Herman Kahn, the Cold War strategist, has this phrase from his book On Thermonuclear War, in which he points to “tragic but distinguishable postwar states.” What he’s saying is the largest nuclear wars are disproportionately worse than smaller nuclear wars, which means that much of the total expected cost there lies with those largest wars. It’s a familiar feature in catastrophic risk; I think we see something very similar when looking at pandemics and biosecurity.

That’s for a few reasons. One of those is, as you pointed out, nuclear winter potentially kicking in. And now it turns out that these very interventions that, as we just established, might be the most important ones from keeping a limited nuclear war from turning into the largest possible nuclear wars, also happen to be the interventions that are very neglected. And from a philanthropist’s point of view, that’s a philanthropic jackpot. That’s exactly what you want.

Luisa Rodriguez: Right. As a person who is hoping to direct philanthropists’ money, that is actually music to your ears: you get to show people this awesome thing to do with their money.

Christian Ruhl: That’s right, yeah.

Deescalating after accidental nuclear use [00:24:23]

Luisa Rodriguez: So let’s talk about what some of those interventions are. There are quite a few of them, and I think they’re really interesting, so I want to go through them one by one. The first one is deescalating after accidental nuclear use. What exactly does that look like?

Christian Ruhl: So back to the car analogy. Let’s say your car suddenly breaks down on the highway: you can honk your horn, you can turn on your warning lights to signal to other drivers you had an accident, you can call somebody to help take care of your car.

So in nuclear crises, that might include that leader-to-leader hotlines exist, and that they’re actually used as intended if, god forbid, something goes wrong and a nuclear weapon accidentally goes off. I have a report on this called Call Me, Maybe? that goes into this a bit more, but essentially the US and Russia have this long history of working together to reduce nuclear risks, and that includes the hotline that was established after the Cuban Missile Crisis.

So if, god forbid, something goes wrong, you can contact the other state and say, “Hey, sorry, please don’t nuke us back.” This actually isn’t a literal phone; it’s called the DCL — the direct communications link. It used to be teletype via cable. Now it’s basically email via satellites.

One big concrete problem here is that China is very bad at answering during crisis situations.

Luisa Rodriguez: Wow, that’s horrifying.

Christian Ruhl: Yeah. So there’s one example here where Chinese leaders didn’t respond to repeated US contact attempts during the Hainan Island incident that was in 2001. So in this incident, Chinese fighter jets got too close to a US spy plane doing routine operations, and the spy plane had to make an emergency landing on Hainan Island. And the US plane contained highly classified technology, and the crew sort of tried to destroy as much of it as possible as they could before being captured. If you read through some of the reports, apparently they were pouring coffee on it at one point.

Throughout the incident, US leaders tried to reach Chinese leaders via the hotline, but the Chinese didn’t answer. So the deputy secretary of state at the time remarked, “It seems to be the case that when very difficult issues arise, it’s sometimes hard to get the Chinese to answer the phone.”

So this was 2001. Scary enough back then. I think with heightened tensions now over Taiwan and over the South China Sea, we can imagine what might happen. A Biden administration official recently said that hotlines that have been set up have just “rung kind of endlessly in empty rooms in China.” So here we have a concrete problem, a concrete funding opportunity that people actually haven’t looked into much: basically to fund a study to understand Chinese attitudes towards these systems, fund track two diplomatic dialogues, see if they can find common ground on, “Hey, maybe pick up the phone?”

Luisa Rodriguez: How do we explain that? That’s insane. How is it not already in China’s interest to use the phone explicitly for the purposes of emergencies? Maybe we just don’t have an answer to that?

Christian Ruhl: I personally don’t have a good answer. I mean, certainly it’s possible that someone might answer during what’s perceived to be a real crisis or something.

Luisa Rodriguez: Sure. A bigger crisis or something.

Christian Ruhl: Exactly. And that it might be in the strategic interest of the country to be ambiguous about what it actually wants to do. Incidentally, this is also relevant I think for other kinds of accidents and catastrophic risks. I think hotlines, when they work well, might be relevant, for example, for AI deployment accidents, communicating with other states about those kinds of risks.

Luisa Rodriguez: Yeah, this just seems bizarre and surprising to me. It just feels like obviously countries that have the capability and may at some point have the interest in deploying nuclear weapons against one another should obviously have the capacity to reach each other during an emergency. And those systems should obviously be airtight: there should be a main thing, a backup thing, a satellite thing, another type of thing. It just seems very much in the interests of the leadership of the countries we’re talking about to have this. And so I’m just quite shocked that it isn’t stronger.

Christian Ruhl: Absolutely, yes. I’ve had the same emotional reaction to this in a lot of ways. Another example of it is track two engagement between the US and China — so, unofficial diplomatic talks. It turned out that there was just a single track two dialogue running between the US and China that focused specifically on strategic nuclear issues. And for the longest time, until some more recent developments, the US and China just weren’t talking at all about these issues, and this was sort of the only space in which that was happening.

So we actually provided some funding to this dialogue, to make sure it keeps going. But just let that sink in: this huge risk, and we’re barely talking about it with each other.

Luisa Rodriguez: Yeah. Interesting. That sounds really worth funding.

Civil defence and war termination [00:30:40]

Luisa Rodriguez: OK, so another one of these right-of-boom interventions you think is promising is civil defence. What does that mean? What does it look like?

Christian Ruhl: So think back to March 2020, and the confusion and fear that many of us felt about COVID, not knowing how do I keep myself and my family safe? Imagine instead of that, we had learned in school, “Hey, we know these outbreaks happen, so if something like this happens, here are some measures that can help.” And imagine the government had taken steps to research pandemic-proof PPE and sent high-quality respirators to every household just in case — not that much money, and protecting the civilian population in case of a war or in case of a different catastrophe. That’s what we’re talking about when we talk about civil defence. Today it’s often called “emergency management.”

So with nuclear war, we’re talking about measures like shelters, evacuation, public education on what to do, PPE again, stockpiles of critical supplies, food. It was always a topic that came up in the Cold War, but it never really got off — but mostly for political reasons, not because it wouldn’t have worked.

Luisa Rodriguez: It does seem like we did more of that in the Cold War. I feel like there’s this cultural meme of “duck and cover.” And it’s kind of funny that we don’t do that, even though it sounds like at least some of it would be reasonable to do. According to some people, we face similarly scary nuclear threats today relative to the ones we were facing then. Arguably that’s not true, but it still seems like probably the risks are high enough that we should be doing something there, if something there would work.

Christian Ruhl: And we have some evidence that some of these measures probably would work. In Nagasaki, there were about 400 people who were very close to ground zero, and took shelter inside of these hillside caves. And these 400 people survived. And not only did they survive, except for the people who were immediately by the entrances to the caves, they survived uninjured. We know there are ways to protect people, right? It is really scary to think about, but it’s potentially worth thinking about.

Luisa Rodriguez: Yeah, I actually didn’t know that. That’s new and surprising to me. Moving to another one, we’ve already touched on this a little bit, but we have hotlines and also just specifically war termination. What do those look like?

Christian Ruhl: So one of the things you want to be able to do, again, if a nuclear war breaks out, is make sure you have a way to communicate with the adversary to say, “Let’s stop this. Let’s find a way to have peace.” Unfortunately, as far as I can tell from public sources and from talking to experts about this, the nuclear hotlines we have seem likely to fail in the event of war. And obviously, you can’t end the war if you can’t communicate with your adversary.

This hotline was implemented, as I said, in 1963. Really early versions were pretty fragile and insecure. There was one kind of funny case where a farmer in Finland accidentally ploughed through a cable in 1965. So they’ve made updates every once in a while. They switched to satellite in 1971, added fax 1984, and switched to email in 2008. But one of the last public examinations we have about hotline resilience is from the ’90s, and they write, “The DCL is not designed to survive or function in a war environment. Its principal component subsystems are essentially unprotected against blasts or other nuclear effects or electronic countermeasures such as jamming.”

So again: a huge problem. Seems obvious that we should try to fix it. I think like a study group in the public to say, you know, we don’t have access to the classified information about what these systems actually look like, but we want to make sure this will actually work.

Luisa Rodriguez: Yeah. Again, I feel pretty shocked. I did not know that the hotlines would fail after a nuclear blast. That’s insane. And I imagine it feels hard enough for leaders trying to deescalate a nuclear war to do that with verbal communication — and without, when you’re just guessing about what another country is thinking, that just feels impossible. So that’s absolutely horrifying.

Christian Ruhl: Yeah. What are you going to do, explode bombs in Morse code or something? I don’t know.

Luisa Rodriguez: It’s bizarre. Truly bizarre. Do we have technology that would survive nuclear detonations and we could just, in theory, implement that, but haven’t? Or do we have to develop something somehow that’s more robust?

Christian Ruhl: I think it gets really complicated. And a lot of the stuff about this I do think is probably classified. So it’s totally possible that I’m wrong about a lot of this. But we know that nuclear weapons states care a lot about the communications links of their own systems, so the NC2 are making sure that that keeps working if a war breaks out. It’s kind of this perennial focus of war planning is ensuring the resiliency of NC2 systems. And it would seem like the very same care and whatever measures are taken to, say, protect electronics from EMP and stuff like that might very well be used for state-to-state communications. Or maybe you make it redundant with multiple satellites, in case it’s like war in space.

There are many things we can think of. Again, totally possible that I’m just wrong about this, but from what we can tell publicly, it would fail.

Mitigating nuclear winter [00:37:07]

Luisa Rodriguez: Wow. Crazy. So another one is mitigating nuclear winter, which is basically a thing that’s hypothesised could happen if enough nuclear weapons were detonated in an area with a lot of flammable material. If that happened, a lot of that flammable material could get lofted up into the atmosphere, block out the sun, and cause massive global cooling. What kinds of interventions are you most excited about in the context of mitigating nuclear winter?

Christian Ruhl: Great question. I think the extent and severity of cooling is kind of disputed. We’ve both talked about this, but I think the basic mechanism of nuclear winter is sound. Most people agree on that, and it seems more likely to occur in larger nuclear wars.

Remind me, actually: when you were looking at this, how many of the expected fatalities came from nuclear winter versus direct effects of blast and fire, if you remember?

Luisa Rodriguez: If I remember correctly, it was something like, the direct effects of the nuclear bombs being detonated in places where humans live would be around 50 million, but the indirect effects of a nuclear winter that affected big chunks of the world might have caused something like 2 billion deaths at least.

Christian Ruhl: Yeah. So this is huge, right? Even if we think some of the estimates from the nuclear winter literature are too high and we cut that in half, it still makes up the vast majority of deaths in a large nuclear war. So this is really one of the things we might want to think about preventing. And strangely enough, it’s a thing that policymakers don’t seem to think about very much at all.

And what kind of interventions might that include? I think targeting policy is a big one. These things are classified, but as far as I’m aware, the possibility of triggering nuclear winter through firestorms in cities is not even a consideration that comes up. It really should be. So again, you can fund high-quality studies to look at this, look at realistic yields and targets, and show, “These are the expected effects. If we change this a little bit, it might look different; if we don’t hit certain cities…” — again, horrifying to contemplate, but again, might really save a lot of lives.

It could also include advocacy around food stockpiling, around developing resilient foods. As you know, there are nonprofits out there working on this, but this really should happen on a much larger scale. It really is a subset of civil defence.

Luisa Rodriguez: Yes. I feel good about those getting more attention and more funding. If you’re interested in how to feed everyone during a nuclear winter, Rob did a really excellent interview with David Denkenberger on the 80k podcast. I think there maybe are two, and the first one was probably my favourite 80k podcast of all time for several years. So I highly recommend that.

Planning for a postwar political environment [00:40:19]

Luisa Rodriguez: OK, our final right-of-boom intervention is planning for a postwar political environment. That just alone sounds very scary to me, and I don’t love thinking about it. But what should we be planning for?

Christian Ruhl: I think one of the things that people don’t appreciate is that even if nuclear war breaks out, and even if humanity survives, and even if civilisation recovers, that that recovery might not be with good values. So we can imagine things like unconstrained competition around AI between multiple authoritarian states. After a nuclear war over Taiwan, we might worry about the risk of locking in certain kinds of political systems, and about totalitarian political systems perhaps being more likely to survive.

Luisa Rodriguez: Sure, and just for context: the reason we might worry this is because for various reasons, AI might make it possible to lock in political systems or value systems by stopping different modes of cultural evolution, for example, by enabling identical digital copies of totalitarian leaders so that there never has to be a regime change, just for one example.

Christian Ruhl: So let’s think about [with which] concrete levers we can actually maybe affect what kinds of political systems might survive after nuclear war. One of these in the US is the continuity of government plans, or COG plans. So there’s like Raven Rock “designated survivor” kind of stuff, making sure that the US government continues in some form, even if there’s a nuclear war.

But if you look back, and look at what some of the Cold War plans were for what to do… There’s a great book called Raven Rock, actually, that talks about this. But let’s take the Eisenhower administration as an example. As I understand it, the plans were completely insane and authoritarian. He had set up this system to, in a time of crisis, a small handful of his best friends would take power, nationalise industries, restructure the government, and basically start this crazy oligarchy.

Now, COG plans obviously are very classified. That doesn’t mean that philanthropists can’t have an impact here. One thing you could do is fund a high-level study group of continuity of government against emerging threats — include nuclear war, include biosecurity, include AI — and do policy advocacy of key decision makers that ultimately make these plans, and emphasise the importance of having mechanisms to return to constitutional democratic government to keep the values that we care about.

There’s actually an example of this in 2002, a right-leaning think tank AEI and left-leaning think tank Brookings worked together to do this continuity of government commission — so a precedent for doing something like this. Again, I think there are really concrete things we can do to make sure that if, god forbid, something like this happens, things go a little bit better than they otherwise would.

Luisa Rodriguez: Cool. That is really motivating. Very good to hear. So those are the interventions. Which one do you think is most promising?

Christian Ruhl: One that I’m really excited about is just war limitation, broadly defined — especially policy advocacy around war planning and execution that bears on the probability of nuclear winter. So actually, at Founders Pledge we are putting our money where our mouths are, and we recently made a three-year grant of $2.4 million —

Which by the way, that puts us as a major funder in the field now — which is crazy, right? That shouldn’t be the case.

Luisa Rodriguez: Wild.

Christian Ruhl: — but to this project called “Averting Armageddon” at Carnegie, led by James Acton and Ankit Panda. Basically, it asks a lot of these questions about war limitation and escalation management over three years, thinking really in depth about what can we do here? They’re asking what limits can we actually come up with? Which ones might stick? What are the technical obstacles, things like hotlines failing, and what can we do to make sure that these things go better?

Luisa Rodriguez: Yeah, that does sound like a great grant to make. And just to reiterate that it is wild that you are now a major funder in the nuclear space with only $2.4 million. That brings us to this weird fact that very few institutions work on these kind of right-of-boom interventions.

Christian Ruhl: Yeah, that’s right. In nuclear issues, we’ve heard this anecdotally that right-of-boom interventions are only a small fraction of the total amount of work.

We looked into this a little bit, tried to quantify it, and it looks like it’s about 3.3% or so of philanthropic funding, at least over the last 10 years or so. It’s kind of challenging to actually come up with an estimate because the right-of-boom / left-of-boom distinction is a little bit fuzzy. But we searched through the funding databases, tried to find any grant that could plausibly be considered right-of-boom, came up with this rough 1-in-30 number, and then ran that by a bunch of nuclear experts. And they agreed, they said yes, literally nobody works on this. Most of them thought that estimate was probably too high. James Acton from Carnegie told me, “1-in-30 is an upper bound. I have to say I’d be pretty surprised if it was as much as 1-in-30.”

Luisa Rodriguez: That’s wild. That’s truly wild. I can imagine a few reasons for this, but before I make guesses, what do you think the most common ones are?

Christian Ruhl: Great question. So I pointed to a report called Philanthropy to the Right of Boom; it’s also in the nuclear report: why do we care if something is neglected? Many reasons, but two of them are: there might be low-hanging fruit to be found, so policy advocacy might be easier when a space is less crowded; but importantly, neglectedness could also be an indicator that something is actually a bad idea, and there’s a reason people aren’t doing it, right?

So we need to look into the reasons that something is neglected. I think there are a couple of bad reasons. So this way of thinking has historically been associated with kind of hawkish Cold War thinking, and it still carries that ideological stain. So it’s like a political, PR, ideological problem.

Luisa Rodriguez: Makes sense. Were there other reasons?

Christian Ruhl: Yeah. You might have different worldviews or moral priorities. So if you think the very existence of nuclear weapons itself is inherently immoral, there’s something about the weapons themselves that makes them evil in a special way, you might actually not want to work on these kinds of interventions. Not everybody has the same worldview. If, on the other hand, you think about the consequences of these things and worry about saving human lives via those consequences, I think the perspective of right-of-boom makes a lot more sense.

We interviewed a lot of experts about this, and one thing that surprised me was the answer was always like, “Oh, it just kind of has had bad vibes since the Cold War. We don’t do this.”

Luisa Rodriguez: Wow.

Christian Ruhl: That’s what it comes down to.

Luisa Rodriguez: Somehow I feel like I get it. I don’t believe it when I inspect it, but when I’m imagining the US government investing in something like systems to make sure they can communicate with another country in the event of nuclear war, I’m like, “How dare they plan for a nuclear war to happen?” It just feels kind of outrageous. It feels to me upsetting and yucky, just really unpalatable that anyone’s even thinking about this. I do kind of get it, but I would hope that the people thinking seriously about what to invest their resources in would inspect that a bit closer.

Are there any good reasons not to fund these?

Christian Ruhl: Yeah, I think so. And just to hammer that home, it does feel yucky. And I personally feel that a lot, working on these issues. It feels abhorrent to think about using nuclear weapons, but at the same time, when we think about it rationally, this is something that we do need to think about.

But good reasons that people might say, let’s not pursue these kinds of interventions: one is that for various reasons, decreasing the consequences of a nuclear war, you might think maybe that actually makes nuclear war more likely — so it makes it seem winnable, it makes it seem less abhorrent, maybe undermines deterrence in one way or another. I lump this all into one kind of category: decreasing consequences increases probabilities.

To respond to that, we can go back to the car analogy again. Let’s imagine we’re in this town where for some reason they haven’t had cars. And cars are new, and it’s been a few weeks and we haven’t had any car crashes. So we’ve come up with traffic lights, rules of the road, driver’s licences, and so on — but we don’t have seatbelts, we don’t have airbags, we don’t have ambulances. And maybe we want to suggest, “Hey, we should think about these bags that could inflate and somehow prevent the crash from being as bad. I don’t really know what it looks like. Maybe we should spend some money on a research project to see what it looked like.”

Then people might say, “Actually, what makes people safe drivers is that they’re worried about crashing their cars.” A couple responses to that: like, maybe. But there are also drunk drivers, and we know from history that nuclear decision makers sometimes get drunk. There are malfunctions, there are accidents, all kinds of things can go wrong.

If we’re thinking about mitigating nuclear winter, and we’re worried about might this make nuclear war more probable, my simple answer to that is that decision makers generally don’t even think about nuclear winter in the first place.

That means that if we’re able to decrease the probability of nuclear winter, that might not even enter into the decision-making calculus. If you look at the historical examples of how decisions get made, what do they think about? They’re not like, “Will 2 billion people die or will 1 billion people die?” They say, “This is horrifying. Many people could die.” We know that humans are scope insensitive from various experiments. And then they think about things like the upcoming election: “I wonder if I look weak if I don’t do this,” right? This sort of rational calculation doesn’t happen.

And if you think about who might die from a nuclear winter, I think horrifyingly, it’s already the marginalised people, people in the Global South living in extreme poverty. And do we think that enters the decision-making calculus of leaders in rich countries? Actually, here’s a thing we do have some evidence for.

Luisa Rodriguez: That’s really dark.

Christian Ruhl: We do have some evidence about the behaviour of leaders and political elite in rich countries — and it’s generally that they don’t do anything about the global poor, starving, and dying. Miserable deaths happen every single day, and except for a small handful of people, we let this tragedy happen right under our eyes. So the idea that that would change during nuclear war just doesn’t make sense to me.

Luisa Rodriguez: Right. So it’s something like if I’m the political elite, and I’m nearby to the decisions about starting a nuclear war, basically, detonating nuclear weapons, and I’m thinking to myself, “Should I do this?,” that is not actually going to be that influenced by whether anyone has taken any measures to make sure that people in the Global South don’t starve to death during a nuclear winter.

Christian Ruhl: Exactly.

Luisa Rodriguez: That’s just not a key consideration for them. And on the one hand, that is incredibly sad and dark and depressing. On the other hand, it means that this kind of risk is actually less worrying.

Yeah, I think I basically at least buy that for some of these. I can imagine the argument being a little stronger for others. So maybe there’s an interesting angle, which is that we prioritise especially highly interventions that seem especially unlikely to enter into the calculus of these decision makers.

Christian Ruhl: Yeah. And what’s happening here is they’re making empirical claims about the psychology of decision making, often without empirical evidence. And I’ll make an offer here: I’d be willing to take a bet with anybody that if you ran an experimental war game about this, decision makers would be fairly insensitive to the numbers. If somebody’s worried about 200 million Americans dying or 100 million Americans dying, I think in the brain of most humans, that’s just like “the end of everything that I care about,” and it’s horrifying, and hard to even think about those numbers.

And at the risk of feeding a fed horse, I want to suggest that maybe something like the opposite is true: that threats might be more credible if they don’t involve the total destruction of your own society.

Luisa Rodriguez: Yeah, that makes sense to me.

Experience of having a stutter [00:53:52]

Luisa Rodriguez: Turning to a totally different topic: you have very generously offered to talk about the experience of having a stutter. So I’m curious to just basically dive right into that, if you’re up for it, starting with what is the experience of stuttering like, from the inside? What does it feel like to not be able to say what you want to say sometimes?

Christian Ruhl: I guess now we get into the emotionally challenging territory, now that we’ve talked about hundreds of millions of people dying in nuclear war.

Luisa Rodriguez: Right. Now for the hard stuff.

Christian Ruhl: Right, yeah. So I think some of my favourite episodes of 80k After Hours have been about mental health, and especially your personal writing and speaking about the topic. That’s one of the reasons I was so excited to come on the podcast, to talk about a disability and a neurological disorder that you can actually hear on a podcast.

So what does this feel like? It’s kind of like your thoughts are trapped inside of your body. So let’s back up a little bit. Stuttering: what is it? It’s this neurological disorder. We don’t really understand it, but it’s now understood to probably have some pretty strong genetic component. It affects about 1% of the population. Most people grow out of it.

And from the outside, it often looks like people are repeating, they’re blocking — so they’re stopping in a specific thing, or they’re prolonging their words. I think from the outside, it sometimes looks like somebody is at a loss for words. But in fact, what’s happening is I have no trouble forming sentences, either in mental language — concepts, images, whatever — or in English in my head. The issue is there’s some sort of disconnect between what I want to say and what my body is doing. It’s not working right.

Luisa Rodriguez: Right. Do you literally have the English word in your head, or is it more that you have the general ideas in your head, and then it’s somewhere between ideas and words? Or is it more like you could literally hear the sentence in your head and it’s about speech?

Christian Ruhl: It’s a really good question. I feel like we could go on a long tangent about this question, about the language of thoughts. I think “mentalese” is a word that people sometimes use. So it’s both, right? I’m able to form ideas and concepts in mentalese, in my head, and I’m able to consciously say them “out loud” in my head fluently. The issue is really translating that into vibrations of the air.

Luisa Rodriguez: Got it, OK. So that’s what it feels like, kind of intellectually. Has your stutter had much of an impact on you emotionally?

Christian Ruhl: Yeah, 100%. I think it can be really emotionally draining. I’m personally fundamentally an outgoing person, and it totally blocks that impulse.

So maybe we can think about your average day, and think about the moments every day that you rely on speaking fluently. Maybe it’s the morning. It’s like 7 AM. You want to have a coffee. You go to your coffee shop, and you’re like, “OK, I’m going to order a coffee.” What kind of coffee should we order?

Luisa Rodriguez: I would like a soy latte with vanilla and peppermint.

Christian Ruhl: OK, that’s great. A soy latte with vanilla and peppermint. Or as I might say it when I try to say it, “A ssss” — that’s what the person behind the counter might hear — and like, totally block. Stand there with an open mouth, looking helpless. And what does the other person see? You think in your head, what are they thinking? Do they think, “Is that guy having a stroke? Should I call an ambulance? Is he on drugs?” Right?

So maybe in the end, you manage to get out the word, or you point towards the board, and it’s like, “Ugh, that was bad,” but you get the point across — like, “I want this specific thing.” And then they ask me, what’s the name for the order. And a frustrating thing that a lot of people who stutter have is that they block on their own name.

Luisa Rodriguez: Oh my gosh.

Christian Ruhl: So do I make up a fake name that’s easier to say? That’s crazy. Or do I try to say my own name and can’t, and then their response is like, “Oh, did you forget your name? Ha ha.” Right? This is like, the morning.

Luisa Rodriguez: That sounds so frustrating.

Christian Ruhl: But let’s imagine you have your coffee in hand, walking out and your hands are full. And you suddenly maybe remember something you wanted to write down for a report you’re working on about nuclear war. Maybe you try to use the voice assistant on your phone. And it’s not designed to work for you.

But that’s kind of what it feels like, to try to paint a picture there. Small moments. Compared to the things that are happening to many people, it’s not a big deal, but there’s all these small moments throughout your life where fluency would be really helpful.

Luisa Rodriguez: Totally. To what extent do you get desensitised to the feeling of like, “That was frustrating. I couldn’t get the word out again.” Or does that get limited at some point, and maybe you feel a bit less frustrated, but it is just still freaking frustrating to not get the words out?

Christian Ruhl: It remains really frustrating. Getting desensitised to it is hard. As I understand it, the latest approach to speech therapy is about this, just being OK with stuttering openly. But that’s easier said than done. Or in my case, both hard to say and hard to do.

Luisa Rodriguez: Imagining it for myself, it is really, really hard to imagine. Just really hard to imagine just accepting this isn’t going to get easier, it’s going to keep happening.

I guess even more personal: do you feel like it had an impact on you growing up? I’d imagine feeling especially awkward as a kid when I didn’t understand the thing quite as well, and maybe other kids didn’t understand the thing quite as well.

Christian Ruhl: Yeah. So I was fortunate enough to grow up in a really loving home with great parents and so on. So that’s wonderful. But you can imagine still, in school, the kid who can’t say his own name or who can’t get a word out when called on in class is going to have a hard time.

So I tried for a while doing speech therapy. For some people that works; for me, it didn’t. At one point, I don’t remember if it was at Cambridge or Oxford, but I’m a big fan of self-experimentation, so I participated in this experimental trial where they were investigating transcranial direct current stimulation and trying to figure out if zapping your brain a little can help. It didn’t, but it was still interesting.

Luisa Rodriguez: Wow. I’m both curious if you think the actual stutter has gotten better, and then I’m also curious if your experience of it has gotten better. I’m just super impressed that you were like, “I’m going to go on a podcast.” And I have to believe that it took a bunch of emotional work at least to get to the point where you were like, “Yes, I want to do that.”

Christian Ruhl: Thank you. Yeah, I hope we didn’t give 30 minutes of content in 90 minutes of time. But the stutter itself has not gotten better for me personally. Again, as I mentioned, a lot of kids grow out of it. I just didn’t.

My emotional response to it I think has gotten better, in the sense of at some point you just have to try being comfortable with being uncomfortable. And like, “I manage this philanthropic fund. It would be good for more people to know about it because I think it does a lot of good in the world, and if more people know about it, maybe they’ll give money to it. So I should go on a podcast so people can hear about it. Ugh, I have to go on a podcast.” So I’m trying to do that more.

And in terms of stuttering less, there’s this concept of stuttering freely — of just like, communication is a two-way street, and it’s not just on the speaker to speak fluently, but also on the listener to be patient. And I think we all have speech patterns of ums and ahs.

Luisa Rodriguez: Totally. Yeah, I like that a lot. And then, you’re kind of touching on it already, but to what extent has having a stutter affected your career?

Christian Ruhl: Maybe I would do more podcasts. This is fun. But one part might be job interviews. Those can be really challenging.

Actually, to go back: other things that are in a similar boat are talking to police or talking to immigration services.

Luisa Rodriguez: Oh, that sounds like a nightmare.

Christian Ruhl: It’s the absolute worst. Because they think you’re hiding something, and they get suspicious. And I already don’t like them.

Luisa Rodriguez: Right. I’m terrified of talking to customs people.

Christian Ruhl: Yeah. But anyway, back to job interviews: those can be really frustrating and challenging. I have to give a bit of a shout-out to the Founders Pledge hiring process here. I think a lot of organisations working on these kinds of issues really emphasise a work task — like, “do expected value calculations on this difficult problem,” or “write a short essay on this philosophical issue” — so it’s entirely about skills, and was like the meat of the hiring process. And I think that, for somebody who has a speech or hearing disability, is super helpful. And once you do that, I feel fine in interviews being like, “By the way, I stutter. I have this thing. I don’t think it keeps me from doing good work.”

Back to how does it affect my career, if I had to think about it, maybe it’s pushed me more into a career focused on writing as an outlet for the language part of my brain.

Luisa Rodriguez: Yeah, that makes sense. Has it stopped you from applying to things? Just the fear of interviews or something?

Christian Ruhl: In the past it has, yeah. Now I’m definitely trying to catch myself and be like, “Nope, I should just apply. I should be in this panel.” Recently, Haydn Belfield and I had written this article and the Bulletin of the Atomic Scientists gave us a prize. They were like, good job on the article, and part of it was speaking at the annual meeting they have, the Conversations Before Midnight. And I was like, “That’s terrifying.” But then I caught myself and I was like, I should just do it. And I stuttered and it was uncomfortable, but it was fine.

Luisa Rodriguez: I mean, that sounds great. I guess my experience of repeatedly forcing myself to do things that sound really terrifying and costly is like, in some cases, it gets easier over time. It’s still really exhausting being like, regularly, I am going to stifle my own fear about doing this, do this terrifying thing like speak at a conference, and then have all the panic afterward about whether I did a good job. And even if it does get easier, it gets easier so slowly over time that it still means that the first 30 times of speaking at a conference are kind of torturous.

I’m impressed that you have the stamina. I feel like there are some things I’ve just given up on. I have a default email that’s like, “I don’t speak at conferences because it makes me too anxious.” So I think it’s really cool and inspiring that you push yourself. Do you feel like it’s important to set limits? That sometimes you give yourself an out to be like, “I don’t have to do that really hard thing”?

Christian Ruhl: Yeah, for sure. I’m totally with you there. We don’t have to be too hard on ourselves.

Luisa Rodriguez: And then how do you decide?

Christian Ruhl: I guess one thing that’s helpful with my job is, in terms of motivation it helps that I feel like I’m genuinely doing good in the world. So let’s say I’m interviewing an expert about pandemic preparedness. It’s much easier to kind of get over myself, because I know that maybe philanthropists can help make grants to mitigate these risks if I write a good report or whatever. So that’s one way of deciding.

Luisa Rodriguez: Yeah, that makes sense. Overall, does it make your job harder?

Christian Ruhl: Yeah. I think grantmaking and research done right ends up being a pretty social job. So you’re talking to policymakers, going to conferences, going to war games, getting coffee with experts. There’s a great article from 2011 called “The elusive craft of evaluating advocacy” that gets into the social part of a job like this. So for example, especially on Zoom, when I talk to people, interview them about research questions, they might say, “I think we have a bad connection.” And I’ll say, “Yeah, but the bad connection is in my head, unfortunately.”

I have a great anecdote about this, actually. So I try to advertise my stutter before I talk to people. I’m like, “Hey, thanks so much for the interview. Just so you know, I have a stutter, so you might hear it on the call.” And usually that’s fine. At this point, the person I talked to was like, “OK, I’m sort of familiar with people who stutter. I actually have really bad PTSD, and it gets triggered by plosive sounds. So people who block on certain letters might trigger my PTSD.” This guy’s served in the military, now he’s like an expert on a specific topic, and he’s like, “Just so you’re aware.” And in my head I’m like, “Shit, I’m going to give this guy a flashback if I stutter.” So that was a specific part that really made my job harder, and I kind of had to really concentrate to be…

Luisa Rodriguez: Oh, god. The vast majority of the time, this is just like, actually not going to harm anyone; giving them a heads up is a nice, great thing to do to clarify, but it’s going to be fine either way. And this is the one time where… I don’t know if everyone knows what plosives are, but it’s like the hard consonant sounds you make. That’s really unlucky. Did that go OK in the end?

Christian Ruhl: Yeah, it was fine. I think we were both fine in the end.

Luisa Rodriguez: Nice. Oof. OK, well, I think we should leave that there for now. But I’m really grateful to you for sharing. And I’d guess people listening are going to value having heard you talk about that.

Christian’s archaeological excavation in Guatemala [01:09:51]

Luisa Rodriguez: So a final question: I happen to know that you worked on an archaeological excavation in Guatemala. I’m curious in general what that was like, and I’m also curious if it had any influence on your interest in the collapse of civilisation and other kinds of existential risks?

Christian Ruhl: Totally, yeah. Yeah, it ended up being kind of life changing for me, in that it did spawn this interest in civilisational collapse, and ultimately in existential risks and the kind of things I work on now.

So one summer, actually 10 years ago now, I was living in Guatemala for a few months and we were working on excavating this Maya settlement. It was a satellite town of the ancient city of Motul de San José in the north of the country. And just a note to listeners: I think we should be careful about making claims about the “collapse” of Maya civilisation, because that’s a really complicated and multifaceted topic. The word collapse might not be right; it really depends on the specific settlements we’re talking about.

With that disclaimer out of the way, I’m just describing my experience here, and kind of thinking about the idea of civilisational collapse. I remember distinctly at one point, one of the layers I was excavating was like this beautiful white stucco — like, perfectly level, better construction than you see in most places today. And all of these artefacts of everyday life of the people who lived there, it kind of struck me in an emotional way that many of the things and people and values that we love and hold dear today could be covered in rubble and dirt if we’re not careful. And I’d like to avoid that fate for our civilisation.

Luisa Rodriguez: That’s really heavy. I think we should leave it there. My guest today has been Christian Ruhl. Thank you so much for coming on, Christian.

Christian Ruhl: Thank you so much.

Luisa’s outro [01:11:50]

All right, 80k After Hours is produced and edited by Keiran Harris.

The audio engineering team is led by Ben Cordell, with mastering and technical editing for this episode by Milo McGuire.

Additional content editing by myself and Katy Moore, who also puts together full transcripts and an extensive collection of links to learn more — those are available on our site.

Thanks for joining, talk to you again soon.