Brain Food

Intellectual nourishment, now available for hungry minds.

Happy Thanksgiving! Good luck with your crazy uncle. If he is telling you to “do your own research” about the unsung benefits of hydroxychloroquine to cure every known ailment, from back ache to economic recession, you may drift away into your screen and pretend you are obliging, when you are, in fact, reading this. In all seriousness, though, I am thankful for you—curious readers that you are—who have prompted me to bake this little slice of the internet in which I explore my intellectual fascinations with you. (You may also find that Fluke makes a nice holiday gift for that special person in your life).

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Concrete Lessons from Ancient Rome (Science)

If you’ve been to Rome, it’s impossible not to marvel at the Pantheon, the largest unreinforced concrete dome in the world. For thousands of years, as sprawling empires crumbled and powerful bombs shook Rome, the Pantheon stood sturdy, an unshakeable edifice, cemented in place since around 126 AD.

Meanwhile, in late 2018, the roof of the staff room within a primary school in southeast England began to show minor signs of wear and tear. Nobody thought much of it, until less than 24 hours later, the roof collapsed, crushing computers, furniture, and toilets. Luckily, it was out of hours, so there were no fatalities. The concrete, unlike in the Pantheon, was just a few decades old.

Several years later, a beam collapsed in another school, triggering a national crisis in Britain, all derived from structural failures of “reinforced autoclaved aerated concrete,” or RAAC. This seemingly state-of-the-art concrete—deemed an engineering marvel in postwar Britain—would catastrophically fail, often without warning. While RAAC is a particularly collapsible mistake, today’s concrete structures are not going to withstand two thousand years and stay standing.

How is it possible that the ancient Romans, with comparatively primitive technology, created a building material that remains superior to modern concrete today?

This question matters beyond historical curiosity. Other than water, concrete is the most used substance in the world.¹ It is also responsible for an estimated eight percent of greenhouse gas emissions globally. (For comparison, all global aviation combined accounts for about 2.5 percent of emissions). It stands to reason that we should probably understand the substance better—including its earliest incarnations—if we’re going to come up with innovations that allow us to reduce that footprint.

For decades, the miracle of ancient Roman concrete was a mystery—confounding even the best civil engineers. Now, the mystery has been solved.

Researchers at MIT cracked the case, so to speak, by focusing on a detail that had been thought to be a hallmark of shoddy construction rather than engineering genius. More specifically, the innovation appears to come from white chunks embedded in the concrete, previously believed to be evidence of “sloppy mixing practices.” In truth, it was the opposite: these little white chunks are likely why the Pantheon is so sturdy.

The chunks are tiny “lime clasts,” made out of bits of calcium carbonate. The gist is this: the ancient Romans were using an advanced form of quicklime that does something spectacular: it heals itself.

As the MIT press release explains:

As soon as tiny cracks start to form within the concrete, they can preferentially travel through the high-surface-area lime clasts. This material can then react with water, creating a calcium-saturated solution, which can recrystallize as calcium carbonate and quickly fill the crack, or react with pozzolanic materials to further strengthen the composite material. These reactions take place spontaneously and therefore automatically heal the cracks before they spread.

Here’s the other amazing bit: when scientists have tried to replicate the ancient Roman approach, they’ve found that they can produce it by heating the materials to *half* the temperature that is typically used to create modern concrete. If such an approach could be used widely—a big if—it could lead to an estimated 70 percent reduction in concrete-based emissions, which would have a bigger impact on mitigating climate change than taking all airplanes out the sky.

This offers a parable for modern scientific progress: we have a strong sense that we know best, that old technology is backward, and that new technology is, by definition, superior. But the case of the Roman concrete illustrates a potent counterpoint: sometimes that assumption can blind us to the simpler superiority of older methods, hiding in plain sight, peppered with the wisdom of our forebears.

Can a Comma Solve a Crime? (The Dial)

It’s widely known that DNA has been a game-changer for crime fighting, as we are constantly but unknowingly shedding little traces of ourselves wherever we go. New research, however, is showing how we shed traces of ourselves in any linguistic record we produce, too, and the field of forensic linguistics is developing new tools to build evidence based on how we, individually, use language. The field is not new—it was famously important in identifying the Unabomber—but it is developing in new and more powerful ways.

In my previous essay, How I Write, I spent little time on syntax or vocabulary, but every writer—whether an author or a person jotting down notes in a diary or penning a e-mail—has an overarching style that tends to replicate itself in each iteration of the written word. This matters because most people now produce countless linguistic traces, as the average person now writes far more than they did in the past. (Consider how many written words are produced through texting, social media posts, and the like; most of the people producing those linguistic constructions would never have written them down before the internet era).

From The Dial:

Sheila Queralt, a forensic linguist based in Barcelona, says many of the cases she works on now involve social media. “It used to be much harder to find material on a suspect, and often we would have to give up the case altogether. But today everyone posts publicly online without even thinking about it, and therefore that material is available for an initial analysis.”

Linguists are quick to point out, however, that authorship attribution is not an exact science. When forensic linguists are brought in to identify authors on criminal cases, they don’t give a definitive answer. Rather, they point to the likely author from a list of suspects.

The essay also points to the fact that unlike DNA, text analysis must contend with the fact that criminals who are leaving deliberate linguistic records (think, for example, of a ransom note) are trying to obscure their identity and may end up deliberately altering the text to appear more or less educated, more or less foreign, and so on. However, what those criminals often miss is any adjustment to their grammar. With new tools, even a distinctive pattern of commas or a stylistic mistake of punctuation can help to solve a cold case.

You Are Who You Meet (Nature)

The microbiome—along with research fields like epigenetics, artificial intelligence, and quantum computing—are cutting-edge realms of mind-blowing research. The more that researchers study our gut, the more they’re realizing how much it matters for determining our health and making us who we are.

But new research finds something truly extraordinary, which further demolishes what I often refer to as the delusion of individualism, the notion prominent in Western modernity that we are masters of our own destiny, somehow magically disconnected from the networks, systems, and cultures within which we build our lives.

Many aspects of health—both positive and negative—have been credibly linked to the microbiome, from hypertension to depression. So, what if the composition of our microbiomes were readily transferable between people? That would point to an astonishing conclusion: that, quite literally, you are who you meet.

Researchers took gut samples from a series of people in isolated rural communities in Honduras. And they found that proximity and social contact do have a major effect on our microbiome. For people who live in the same area but don’t interact, there was a 4 percent overlap of microbial strains in the gut. That convergence more than tripled for those who live in the same house, to 13.9 percent.

But what was most striking, perhaps, is the fact that people who regularly interacted on a social basis had almost as much of an influence as those who lived together. People who spent their free time together in a social context had a 10 percent overlap in their gut bacterial strains. And friends of friends even have overlap, too, a trace of our social chains literally embedded within our bodies.

Relax, though, as this is not bad news:

But people should not avoid social interactions for fear of “catching” others’ microbiomes. Social interactions can spread components of healthy microbiomes and have myriad other benefits. Valles-Colomer says, “Close contacts are not bad for us. The opposite — they are beneficial!”

Nonetheless, choose your friends carefully! They’ll literally change what’s inside your gut.

The Forces of Chance (Aeon)

I am a self-proclaimed disillusioned social scientist. I have serious reservations about how social research is conducted—and whether the dominant paradigm in how we learn things about our social world is actually helping us navigate a moment of immense social peril. We need more interdisciplinary, forward-looking complexity research and less backward looking monodisciplinary obsessions with the always disappointing search for what I call “the Holy Grail of Causality.”

This essay, which I published in aeon last month, isn’t going to make me many social scientist friends. Expanding on some ideas in Fluke, it’s a rather pointed critique of modern social research, which, in my view, condenses much of our world into grotesquely simplified models that too often fail to help us avoid problems.

These two paragraphs give you a flavor of the essay:

In the 1970s, the British mathematician George Box quipped that ‘all models are wrong, but some are useful’. But today, many of the models we use to describe our social world are neither right nor useful. There is a better way. And it doesn’t entail a futile search for regular patterns in the maddening complexity of life. Instead, it involves learning to navigate the chaos of our social worlds…

…By smoothing over near-infinite complexity, linear regressions make our nonlinear world appear to follow the comforting progression of a single ordered line. This is a conjuring trick. And to complete it successfully, scientists need to purge whatever doesn’t fit. They need to detect the ‘signal’ and delete the ‘noise’. But in chaotic systems, the noise matters. Do we really care that 99.8 per cent of the Titanic’s voyage went off without a hitch, or that Abraham Lincoln enjoyed most of the play before he was shot?

Some of the critiques I’ve received on this essay fixate on my attack on simplistic regressions (which, I’m afraid to say, do foolishly remain one of the main workhorses of social research). But the overarching point is that most social research has a surprisingly dismal track record in anticipating or preventing needless human catastrophes.

We would be much better served if the guiding principle of social research wasn’t to try to tease out egregiously simplistic patterns in pursuit of finding a mythical pure singular causality from past data. Instead, as I argue, we should take complexity science and chaos far more seriously, while being overtly forward-looking, with a laser-like focus on solving avoidable problems.

The Mysterious Russian Shortwave Radio (BBC)

This story is wild—utterly bizarre, fascinating, and providing a lifetime supply of speculation for your conspiratorial mind. The upshot is that there is a mysterious and apparently Russian-run shortwave radio station that has been continuously broadcasting seemingly meaningless static, occasionally laced with a coded phrase or two, for the last several decades. There’s some reason to believe it may be related to espionage, but nobody seems to know for sure. Read it for yourself.

Memories of Murder (Film)

This is a 2003 Korean mystery thriller, one of the earlier works of Bong Joon-Ho, who came to Western acclaim primarily through Parasite. It’s loosely based on a series of serial murders that took place in the late 1980s and early 1990s. It’s a masterpiece—gripping, atmospheric, with plenty of subtle flourishes that convey meaning, so long as you’re paying attention.

It also completely subverts many of the standard tropes of police procedurals, which, in Western film, tend to portray the brooding police officers working a cold case as heroic caricatures rather than flawed, nuanced individuals.

If you like Korean cinema or you like murder mystery/thriller type films that have more insights into human nature than your standard, run-of-the-mill Netflix true crime documentary, Memories of Murder is worth checking it out. It often appears on lists of the best mystery films of all-time.

Intriguingly, the actual murderer was unknown in 2003 when the film was made, but the serial murders were finally solved in 2019, more than thirty years after the killings began.

Gladiator II (Film)

One of the first DVDs that I bought as a teenager was Gladiator, the Russell Crowe epic that has one of the most gripping opening battle scenes in cinema history. It’s a film that effectively brought ancient Rome back to life (even though it had one crucial, lamentable omission).²

The second film, as sequels go, delivers on entertainment. It’s nowhere near as good as the first, but if you want to be transported to a visually striking, quasi-interesting Roman epic, then, sure, on some level it works.

But I wanted to mention this film for a different reason: it illustrates the point I made in the essay on the “surefire mediocre” when it comes to the visual effects.

At some point, it feels like bigwigs in Hollywood convinced themselves that scripts and dialogue and stories matter less because what audiences really crave is three hours of bad, over-the-top CGI that makes movies look like video games.

This is baffling to me, because the modern golden age of television was launched with shows that are driven by compelling characters, fascinating storylines, and narrative depth. Consider semi-recent TV shows that linger with their cultural impact: The Wire, Breaking Bad, the Office, Chernobyl, Sherlock, Happy Valley, Bojack Horseman, Downton Abbey, none of which relies much on visual effects.

Meanwhile, Amazon spent nearly a billion dollars on a malformed video game-style CGI fest masquerading as something vaguely related to the Lord of the Rings. It flopped, with a reported 63 percent of viewers abandoning the series after they started watching. (I love The Lord of the Rings books and films, but even I couldn’t make it past the first episode of that Amazon sludge).

We are the Storytelling Animal—and our minds are swayed in lasting ways far more by good narratives, interesting characters, and moral puzzles than digital explosions. (I lament, however, that the biggest box office hits are often simple, forgettable films heavy on the visual effects: Avatar, Avengers, Jurassic World, and so on).

This is my long, curmudgeonly preamble to saying that Gladiator II undercuts its strengths when it commits the CGI error in a comically bad scene involving baboons. These creatures seem to have been imported from someone’s surreal nightmare—of what a freakish bodybuilding monkey might look like if it hit the gym, shaved aggressively, then mainlined steroids for the duration of one or two emperor’s reigns. The entire point of a historical epic is that it’s supposed to recreate the past, not transport ancient Rome into the World of Warcraft.

In short: I give it one thumb up and one big harumph.

Happy Thanksgiving / Happy Thursday!

Thank you for reading The Garden of Forking Paths. If you’d like to support my work to keep this sustainable—and unlock all 160+ essays in the archive—please consider upgrading to a paid subscription. I would be very thankful indeed.

1. Concrete today is typically made with so-called Portland cement, which was invented in England in the early 19th century. People sometimes mix-up (pun intended) cement and concrete. Think of cement as the flour and concrete as the bread. You mix cement with water, sand, rock or other aggregates, and you get concrete.

2. Can you believe—I had to double-check this as it was so astonishing—that there is nothing in the first film or the sequel about the genius of the Roman concrete!? Imagine a scene with Crowe/Maximus giving a rousing speech about the virtues of self-healing lime clasts, in the Colosseum no less (!), before vowing his revenge on the emperor and beheading a man. It would have made gripping cinema.