Cutter Wood is an author whose work has appeared in Harper’s, Discover, The Virginia Quarterly Review, The Paris Review, and other publications. He is the recipient of fellowships from the National Endowment for the Arts and the Bread Loaf Writers’ Conference, and he was the Jenny McKean Moore Writer-in-Residence at George Washington University.
What’s the big idea?
Our bodies continuously shed material, whether it’s the mucus that coats and protects the inside of the nose or the wastes we flush down the down the toilet or the 20,000 breaths we exhale each day. Earthly Materials is about all those things that come out of the human body. The funny thing isn’t that we shed this material, it’s how much effort we often put into pretending we don’t. We cough into our elbows and spray air freshener in the bathroom and turn our heads to cry. But these materials are fundamental to who we are, both as individuals and as a species.
Below, Cutter shares five key insights from his new book, Earthly Materials: Journeys Through Our Bodies’ Emissions, Excretions, and Disintegrations. Listen to the audio version—read by Cutter himself—in the Next Big Idea App.
1. Civilization begins with waste management.
If you could go back four thousand years or so to the area between the Tigris and Euphrates rivers, in what is now modern-day Iraq, you would find some of the largest human settlements Earth had ever seen. There were tens of thousands of people living and working in close proximity. They lived in mudbrick structures, rode on chariots, played bull’s head lyres, and worshipped gods with names like An and Ninhursag. They were living in what were then relatively new inventions: cities. These cities, with their specialization of labor, allowed human civilization to blossom. Though we often think of civilization in terms of its intellectual achievements—theater or religion or writing—these cities relied on something far less cerebral.
What you find if you dig into the ruins of ancient Sumer are some of the very first toilets. These systems of waste management were nothing like the tubular superhighways that now ferry away and treat the collective effluence of several million people each day in cities like Tokyo and New York, but they still reveal something essential about human civilization. Whether it was the Cloaca Maxima, the great sewer of ancient Rome, or Eugene Belgrand’s massive reengineering of the Paris sewer system in the 19th century, the project of civilization has always been, at its most basic level, about collectively dealing with what comes out of each individual’s body.
2. The body is the politic.
Sewer systems are the most obvious example of the way we cede some of our bodily autonomy to coexist in society. Every time we breathe or cry or urinate, we are negotiating an uncomfortable and sometimes untenable truce between our bodies and society. Our lives are governed by a host of laws, social mores, superstitions, and misconceptions about our bodily materials. One of the challenges now, as we’ve learned more about our bodies, is balancing these personal rights and public responsibilities in a way that’s thoughtful and informed.
We experienced this first-hand at the height of the COVID-19 pandemic. We’ve long accepted regulations concerning many bodily wastes. There’s even a passage in Deuteronomy about how to dig a latrine. But we had never, at a societal level, regulated something like breath, and the process of doing so revealed exactly how difficult such societal negotiations are. The mask became, and remains to this day, a political tinderbox.
“We’ve long accepted regulations concerning many bodily wastes.”
The need to adjust behaviors in new and uncomfortable ways will probably only occur with more frequency as our understanding of the body advances. We’ve learned more about the human body in the past hundred years than we did in the hundred thousand years preceding, and yet we still often operate according to laws and traditions that date back millennia. We’ve got a lot of catching up to do.
If you swab the mucus on your cheek and send it to a private company to decode your DNA, who owns that information? When your waste flows into a public sewer, whose property is it? These aren’t philosophical dilemmas; they’re real legal questions. Cities across the country conduct routine wastewater surveillance to track infections, and the bankruptcy of 23andMe has the potential to expose the most sensitive data of millions of people. How we choose to acknowledge and accept the permeability of the human body is going to dictate a lot about how we develop as a society.
3. You are what you excrete.
Part of the reason we’re so sensitive about our body’s excretions is that they say a lot about who and how we are. Physicians evaluate stool samples using the Bristol Stool Scale to determine a patient’s gastrointestinal health, and the spinnability of a pregnant woman’s cervical mucus is used to estimate her likelihood of experiencing a miscarriage. Laboratory medicine itself began with the study of urine, and urinalysis remains a staple of many doctor’s appointments. The hue of urine can be used to diagnose everything from bladder cancer to porphyria while the scent can indicate diabetes or smoke exposure or even obscure ailments like Maple Syrup Urine Disease. Even the frequency of urination can tell you about a person. During the war in Iraq, the anxiety of some soldiers manifested as a frequent need to urinate.
“Our body’s excretions say a lot about who and how we are.”
Possibly the most famous and ubiquitous use of urinalysis, however, is the pregnancy test. Though we know it now in the form of plastic sticks sold in every drugstore, as recently as the 1970s, the process was stranger. It involved a toad. If a woman wanted to know if she was pregnant, she visited her doctor and submitted a urine sample. The sample was then injected into a Xenopus toad, and the toad was placed in a jar atop a perforated platform. The next day the jar was checked. If the toad had laid eggs, the patient was pregnant.
The method was far less convenient and humane than the one we use today, but it drove home how potent a cipher our effluence can be for the state of our own organism. It can literally alter the physiology of another animal.
4. We’re more connected than we realize.
Set back behind one of the main quadrangles on MIT’s campus is the school’s biogel lab, what’s popularly known as the mucus lab. The discoveries made by the scientists there have the potential to change the way we conceptualize ourselves entirely. We produce a significant amount of mucus, approximately a gallon a day. It coats our nasal passages, eyes, lungs, and digestive tracts, and it is not just a filter that keeps germs and contaminants from entering our bodies. Its main job seems to be less about keeping things out than keeping them in.
Scientists at the mucus lab have discovered that rather than playing the role of the bouncer, mucus is more like a maître d’. It plays host to one of the densest ecological communities ever documented: the human microbiome, a living colony of wildly diverse microbes numbering in the thousands of species. Not only are these customers countless—recent estimates give the microbiome three times as many cells and far more DNA than the body itself—but some of them, like staphylococcus aureus, are remarkably virulent.
“We produce a significant amount of mucus, approximately a gallon a day.”
Yet somehow, in ways we’re only beginning to understand, mucus feeds them, tames them, and turns them into a functional commensal community. This microbial community helps to carry out digestion, creates the scents that we think of as our own, and generally undermines the idea of the body as a simple, single thing. As if that weren’t enough, we are continually trading these microorganisms with one another, connecting us in ways we can’t see, let alone conceptualize.
It’s really and truly miraculous. If we can understand how mucus enables all these species to cooperate, it may offer some insights into how we can coexist, as well.
5. Embrace the mess.
We’re a mess. Part of living in society is simply accepting that messiness, both others’ and our own. Our materials have often been an impediment to people coming together, but they don’t have to be. If we illuminate them with understanding and approach them with humility and a sense of humor, we can establish far stronger and more stable connections as individuals and as a society.
Something I thought of often while writing this book is a story from Richard Burton’s version of The Thousand and One Nights, about a man named Abu Hassan who decides to get married. He throws a lavish wedding—stuffed goat, whole roasted camel, five kinds of sherbet—and invites everyone in town. After the feasting, his bride enters, and the company, stunned by her beauty, falls silent. Elated, Abu Hassan rises from his divan to greet her and lets slip what Burton calls “a great and terrible fart.” The man is humiliated. He flees not only the city but the country, wandering for ten years, until at last, overcome with homesickness, he decides to return. He comes back in disguise, sneaking through the streets for seven days and seven nights to see whether his transgression has been forgotten. Having satisfied himself that it has, he is finally on his way to return home when he passes the door of a hut and hears a girl asking her mother what day she was born. “My daughter,” says the mother. “You were born on the night Abu Hassan farted.” The man flees once more, never to return. It’s funny not because of the fart but because of Abu Hassan’s reaction. People fart all the time. The fart didn’t’ ruin his life; his response did.
It reminds me of an old Sumerian proverb. Sumerians were the first to master writing, and in a scribal school in the city of Nippur, archeologists discovered a clay fragment bearing the first joke ever recorded. It translates loosely as follows: What has never happened since time immemorial? Someone didn’t fart in their lover’s lap.
It’s strange to say, but I think there’s a great deal of wisdom in that joke. We would do well to remember that no matter how high we build our skyscrapers or how far we peer into the cosmos, we always have one thing in common.
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