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Last week we talked about chemotherapy. This week we’re going to talk about radiation, but not metaphorical radiation, actual radiation. And not even the radiation used in radiation therapy for cancer. We’re going to talk about the worst radiation of all, the radiation from nuclear weapons, or at least that’s where we’re going to start.

On August 6, 1945, Tsutomu Yamaguchi had finally reached the end of a three month long business trip to Hiroshima, and was finally ready to leave the city. After having to return to the office to retrieve something he forgot, he was walking near the docks when the Enola Gay dropped the first atomic bomb. The shock wave from the explosion “sucked Yamaguchi from the ground, spun him in the air like a tornado and sent him hurtling into a nearby potato patch.” In addition the explosion “ruptured his eardrums, blinded him temporarily, and left him with serious burns over the left side of the top half of his body.” Afterwards he managed to make his way to an air-raid shelter where he spent the night, and the next day he set out again for his hometown of… Nagasaki, where he received further treatment.

Despite being heavily bandaged, he reported for work on August 9th, and was in the middle of describing the Hiroshima explosion to his supervisor when the Bockscar (I think this is the first time I’ve heard the name of the second plane) dropped another atomic bomb. Both times Yamaguchi was around 3 km from the explosion, but this time, being inside, he was not tossed around or burned, though he suffered from high fever and vomiting for a week afterwards.

Yamaguchi has been called the unluckiest man in the world, and it does sound pretty awful to have been present both times nuclear weapons were used in anger. But what’s interesting is that despite being relatively close to ground zero on both occasions, he survived to the ripe old age of 93. Which is not to say he didn’t have problems related to his exposure in the immediate aftermath, and even later in life, but despite being present at not one, but two nuclear explosions it didn’t shorten his life. Is this just a lot of luck later in life balancing out his initial unluck? Should he have died young, but just beat the odds? According to a paper published last year, no, he wasn’t lucky, the irradiation he was subjected to may have actually lengthened his life.

The paper I’m referring to is titled Low-dose radiation from A-bombs elongated lifespan and reduced cancer mortality relative to un-irradiated individuals. And its central claim is right there in the title, low-dose radiation (technically ionizing radiation, but I’ll be using just ‘radiation’ throughout) didn’t shorten the lifespans of those affected by it, it lengthened them. I imagine for most people this conclusion will be surprising. The reason for this surprise, and the chief villain of the paper is the idea that radiation is the worst thing ever, or what the paper describes as the linear no-threshold hypothesis (LNT). “Linear” meaning that the harm of radiation is always proportional to the dose, and “no-threshold” meaning that there isn’t any point at which it isn’t harmful. According to LNT, radiation, no matter how small the dose, is always harmful. There is no safe level of radiation, and certainly no beneficial level of radiation. As I said LNT is the chief villain of the paper and the authors describe it thusly:

Average solid cancer death ratios of… A-bomb survivors… were lower than the average for Japanese people, which is consistent with the occurrence of radiation adaptive responses (the bases for radiation hormesis), essentially invalidating the LNT model. Nevertheless, LNT has served as the basis of radiation regulation policy. If it were not for LNT, tremendous human, social, and economic losses would not have occurred in the aftermath of the Fukushima Daiichi nuclear plant accident. For many reasons, LNT must be revised or abolished, with changes based not on policy but on science.

Elsewhere they describe LNT as “spurious”, with a “seriously flawed history”, and “no convincing [supporting] data”. Now I’m not an expert in this field, and it’s always possible that their conclusion is wrong, but I would bet that they’re right. For one thing, though I haven’t audited their data, it clearly shows that A-bomb survivors lived longer, on average, than a control group of Japanese who were nowhere near the bomb. But beyond that their claim rests on the assertion that LNT advocates neglected to consider hormesis, or what amounts, essentially, to biological antifragility. Not only am I a huge believer in hormesis (and antifragility) but as part of that I’ve seen lots of examples of people overlooking it. Which is to say, it’s not just with respect to radiation that people apply a linear no-threshold hypothesis, people apply it to just about everything that can cause harm. Creating the widespread belief that if something has been shown to cause harm at any level, that there is then no level at which it doesn’t. I don’t think it’s an exaggeration to say that an overarching linear no-threshold hypothesis may be one of the defining features of our era.

There are many examples of this, most take us from the realm of biology to the realm of psychology, and I will admit that I’m making that jump somewhat casually, but I will return and shore it up. But first some examples, One is Brené Brown, who I talked about a few posts ago and who, as far as I can tell, takes an LNT stand on shame. That there is no level of shame which isn’t harmful. You also see it in schools where there is, in effect an LNT around bullying, or even unkind words. The #metoo era has brought it to interactions around sex, where there is no safe amount of discomfort for a woman to experience. Now to be clear, maybe there is no safe level in all three of these examples. I freely admit I don’t have any proof that there are safe or beneficial levels of shame, or bullying or discomfort. But there is significant proof in other areas, and here’s where I start to shore up that jump from biological to psychological. To do so I turn to The Coddling of the American Mind.

I have already touched on Coddling in a previous post, but upon reflection, particularly in light of some of my recent posts, I may not have given it the space it deserves. To begin with it’s a great book, and this is not just my opinion, I know several people who’ve read it and enjoyed it. This includes my daughter, who generally only reads Rowling and Green. Coddling has mostly ended up taking a position on the right in the larger culture war, but the authors, Greg Lukianoff and Jonathan Haidt are pretty liberal, and thus the picture they paint of today’s youth (the subtitle of the book is “How Good Intentions and Bad Ideas Are Setting up a Generation for Failure”) is as objective as anything is likely to be in this day and age. At least in my opinion.

But we were talking about the linear no-threshold hypothesis. You would be surprised if they actually mentioned it, particularly by that name, and they don’t but they end up describing a nearly identical concept, that of “safetyism”.

“Safetyism” refers to a culture or belief system in which safety has become a sacred value, which means that people become unwilling to make trade-offs demanded by other practical and moral concerns. “Safety” trumps everything else, no matter how unlikely or trivial the potential danger. When children are raised in a culture of safetyism, which teaches them to stay “emotionally safe” while protecting them from every imaginable danger, it may set up a feedback loop: kids become more fragile and less resilient, which signals to adults that they need more protection, which then makes them even more fragile and less resilient. The end result may be similar to what happened when we tried to keep kids safe from exposure to peanuts: a widespread backfiring effect in which the “cure” turns out to be the primary cause of the disease.

The emphasis is mine, and that sentence is essentially a restatement of LNT, only applied to all danger, not just the danger of ionizing radiation.

When I crossed over from talking about LNT as it applies to radiation to talking about LNT as a broader psychological and cultural phenomenon in the form of safetyism. I was actually making two assertions: first, that LNT or something nearly identical existed in this additional space, and that it corresponds to what Haidt and Lukianoff call safetyism and second, that safetyism is similarly “spurious”, with a “seriously flawed history”, and “no convincing [supporting] data”. I would hope that the broader existence of LNT/safetyism is more or less self-evident. If not I would ask you to give further consideration to things like microaggressions, safe spaces, trigger warnings, and massive public shaming over minor infractions. All things which are premised on there being no minimum acceptable level of discomfort.

This leaves us with showing that safetyism causes harm. I would think that Haidt and Lukianoff’s description of the feedback loop is a very good start. Beyond that, as might be expected, they bring up the hygiene hypothesis, which I discussed just a couple of posts ago, and where I further made the argument that there is probably a psychological version of it. At the time I hadn’t really considered the LNT angle, but you could certainly imagine that if psychological stressors work anything at all like immune system, and further if there is any mental hormesis, then an attempt to eliminate all emotional stress would cause analogous problems.

The key thing to consider, as I’ve been arguing from the very beginning, is that, in general, humans are antifragile. And we should be more suspicious of philosophies which claim that they aren’t than those which claim that they are. Haidt and Lukianoff agree, pointing out that the current push to identify and eliminate things like microaggressions, triggers, etc. represents a “fundamental misunderstanding of human nature and of the dynamics of trauma and recovery.” And that even if you actually are suffering from something like post-traumatic stress disorder (PTSD) “avoiding triggers is a symptom of PTSD, not a treatment for it.” In support of this they include a quote from Richard McNally, the director of clinical training in Harvard’s Department of Psychology:

Trigger warnings are counter-therapeutic because they encourage avoidance of reminders of trauma, and avoidance maintains PTSD. Severe emotional reactions triggered by course material are a signal that students need to prioritize their mental health and obtain evidence-based, cognitive-behavioral therapies that will help them overcome PTSD. These therapies involve gradual, systematic exposure to traumatic memories until their capacity to trigger distress diminishes.

All of this is to say that there is a safe and even beneficial level of discomfort and even trauma. And this applies not just to normal individuals, but beyond that to individuals suffering from genuine, clinical, psychological trauma.  That when we deprive people, especially children, of this discomfort under the principle of safetyism that we do real harm. As Haidt and Lukianoff’s summary explains:

Children, like many other complex adaptive systems, are antifragile. Their brains require a wide range of inputs from their environments in order to configure themselves for those environments. Like the immune system, children must be exposed to challenges and stressors (within limits, and in age-appropriate ways), or they will fail to mature into strong and capable adults, able to engage productively with people and ideas that challenge their beliefs and moral convictions.

Haidt and Lukianoff spend most of the rest of the book examining the current, unproductive way in which college students engage with ideas which challenge their beliefs, and it’s all very interesting, but I don’t have the space to go into it here. Also I think it’s a problem that’s been very well covered even for people who have never heard of Coddling or Haidt and Lukianoff. What I’m more interested in examining is where to draw the line on things like discomfort or radiation if we’ve decided that it’s a bad idea to draw the line at zero.

This is not the first time I’ve addressed the question, and in fact when I initially brought up “The Coddling of the American Mind” the title of that post was How Do You Determine the Right Level of Suffering? And my thought process then was largely the same as it is now. If some suffering is needed for healthy development how do you determine how much suffering to allow? Even if you just choose to ignore rather than allow, how do you do that? And do you ignore some suffering, but not others? How is that choice made? Would ignoring it be enough or do you end up having to intentionally causing suffering? Would any of this need to be legislated in order to work? If so how on earth would you pull that off? Replace suffering with trauma or even just challenges and the questions largely remain the same.

One big part of the problem is that up until recently we could do everything in our power to reduce suffering and there was still sufficient suffering built into existence for everyone to get their “daily recommended allowance”. Less than 50 years ago young men could still be drafted to go fight and die in a war. 40 years ago my parents could let me wander around in the wilderness for hours doing who knows what and no one thought it was particularly unusual (a story I told in that last post). But technology and progress have changed things. Now kids are always reachable with smartphones, and they generally don’t wander around outside anyway because they’re inside posting on social media or playing video games. And there are no more wars between the great powers, and no more need for a draft. People still fight and die in wars, but on a completely different scale. Interestingly, some people think this reduction is all because of the A-bomb.

Returning to the A-bomb, one of the reasons I started with radiation is that it’s an early example of dealing with rapid technological change, and its associated dangers, and it’s not an encouraging one. According to the paper I mentioned earlier, the linear no-threshold hypothesis traces its origin all the way back to 1927. This is important because it means we’ve had over 90 years to get the science right, and instead, if anything, we’re more frightened of radiation than ever. While at the same time the case for accepting the dangers of radiation is as strong as it’s ever been.  Of course, I’m mostly talking about nuclear power. I have made my case for nuclear power previously, so I won’t rehash it here, but obviously global warming plays into it. (Though perhaps not as much as you might think.)  And despite increasing fears of that from nearly all quarters, nuclear power generation declined, as a percentage of all power generation, from 16.5% to 9.5% between 1993 and 2015.

One might be inclined to blame this mostly on the Fukushima disaster, but that didn’t occur till 2011, and the decline was pretty steep already (which is to say that since global generation is increasing that nuclear generation in absolute terms has been basically flat since 2000.) Speaking of Fukushima, as was already alluded to in the initial quote, the authors of the paper feel that LNT created undue burdens not only in Fukushima, but also at Chernobyl. Claiming:

If it were not for LNT, evacuation would not have been necessary in Chernobyl or Fukushima.

Back in the post where I made my case for nuclear power I mentioned Chernobyl, and it’s worth revisiting that section:

It doesn’t take much searching to find articles talking in excited terms about the amount of wildlife found in the Chernobyl Exclusion Zone (CEZ). One article declares that it’s a nature reserve. Another mentions that within the CEZ wildlife is flourishing. This was unexpected, in one article from National Geographic I came across, they quote a biologist who “studies Chernobyl” (one wonders if his studies have included a visit) as predicting that when the author of the article goes to Chernobyl that he won’t “see any roadkill in the exclusion zone—and would be lucky to hear any birds or see any animals.” Instead the author reports:

Walking along sandy firebreaks used as forest highways…we found the tracks of wolf, moose, deer, badger, and horses. I counted scores of birds: ravens, songbirds, three kinds of birds of prey, and dozens of swans paddling in the radioactive cooling pond.

The article goes on to report that in a study of 14 species of mammals one scientist found no evidence that any of those populations were “suppressed” within the CEZ.

I am sure that there are some health impacts on this wildlife and positive that the CEZ is not without its negative effects. I’m sure that if people were allowed to live there, that there would be higher rates of cancer, among other things. But, also recall, that this is the worst of the disasters, combined with the least cost and effort at cleanup.

One of the reasons I wanted to revisit that section is that I think I may have been wrong. I said that I was “positive that the CEZ is not without its negative effects.” I am no longer positive of that. It’s possible that just as low-dose radiation extended the lifespans of the Japanese A-bomb survivors that it has had a positive effect on the wildlife of Chernobyl, above and beyond just the removal of human interference. But because of the widespread belief in LNT, scientists assume that there must be some awful effect. So awful that one even claimed you would be lucky to spot any birds or animals, when the opposite ends up being true.

As I said unfortunately it’s not just with respect to radiation that LNT holds sway, it’s also present nearly everywhere you look in the form of safetyism, and one the reasons I’ve been bouncing back and forth is that both engender a similar level of panic.

Just yesterday I came across what may be, to this point, the most extreme example (though I’m sure in the future I’ll see something even more extreme). It came out of a story about a fight over building a halal butchery. The proposed site was nowhere near anything residential but it was near a lot of pet related businesses. And as a result, people pushed back on behalf of their pets. But really, it’s one comment that perfectly encapsulates what I’m talking about.

Knowing that my dogs may be walked by a business that holds chickens in a windowless room before their throats are slit while fully conscious does not make me feel that my dogs are in a safe environment.

Not only is this, objectively, ridiculous, but it perfectly illustrates the unwillingness to make trade-offs and compromise that Haidt and Lukianoff talked about. Earlier, I said I wanted to do two things. First I wanted to show that we are dealing with a cultural and psychological form of LNT, which has been labeled safetyism. Second I wanted to show that this absolute prioritization of safety is counter productive and harmful. Here, at the end, I think it would be useful to pull together a list from everything I’ve said thus far of the ways it’s harmful:

  1. It makes people unwilling to compromise, and given that compromise is essential for a functioning society, safetyism has contributed to the horrible political fracture we’re currently seeing.
  2. There’s a misallocation of resources. We spend time and money eliminating things which not only aren’t harmful, but which are probably beneficial.
  3. It creates a feedback loop. Safetyism leads to fragility, fragility means that much more attention needs to be paid to safety which in turn produces even more fragility.
  4. A certain level of stress, suffering, trauma, and/or danger is necessary for healthy development. Safetyism deprives us of that.
  5. By denying human antifragility it creates widespread fragility.

As I said, even if you’re entirely onboard with my conclusions, deciding how to increase suffering is a hard problem. But to borrow from that wisest of all sages, G.I. Joe, perhaps knowing that it’s a problem is half the battle.


I worry that referencing something like the G.I. Joe cartoon which only ran for three years in the mid-80s may be both horribly obscure and horribly out of date, but I also figure obscure, curmudgeonly stuff might be the definition of my niche. If you agree, or even if you just also remember G.I. Joe, consider donating.