We’re in the coldest season. We’re in the shopping season. We’re in the season of hygge. All the cues point to buying yourself a new cozy sweater. Don’t do it, until you hear what Atlantic staff writer Amanda Mull has to say about the cratering quality of knitwear. For years I’ve wondered why my sweaters pilled so quickly, or why they suffocated me, or smelled like tires. And then I read Mull’s recent story titled “Your Sweaters Are Garbage.” It turns out that international trade agreements, greedy entrepreneurs, and my own lack of willpower have conspired to erode my satisfaction.

In this episode of Radio Atlantic, we talk to Mull, who writes about why so many consumer goods have declined in quality over the last two decades. As always, Mull illuminates the stories the fashion world works hard to obscure: about the quality of fabrics, the nature of working conditions, and how to subvert a system that wants you to keep buying more. “I have but one human body,” she says. “I can only wear so many sweaters.”

Listen to the conversation here:

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The following is a transcript of the episode:

[Music]

Hanna Rosin: When it started to get pretty cold, I opened up the drawer where I keep all my sweaters. I have so many sweaters in there. And you know what? I hate all of them. Even the ones that are supposed to be ugly.

Because I was looking at my own closet, in my own bedroom, I figured this was my problem—I was just in my own private hell—until I saw the headline: “Your Sweaters Are Garbage.”

It was an article by staff writer Amanda Mull, who is my guru of consumer dilemmas.

Now, Amanda had done her own thorough sweater investigation, which was inspired by Nora Ephron’s great love letter to cold weather and NY city: When Harry Met Sally.

For sweater lovers, this movie holds a special place. And it has to do with one, enduring image in the movie:

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Amanda Mull: Billy Crystal is in his new, single-guy apartment, squatting in front of one of the big windows in that apartment, and he is wearing, you know, ’80s jeans and a really beautiful, cabled, ivory fisherman sweater.

And the sweater is, like, it’s incredible. It’s really lush. It’s really, like, oversized in the right ways. It is a great, great sweater.

Rosin: Recently, actor Ben Schwartz recreated the photo on his Instagram.

Mull: And he was wearing jeans and in front of a window and, you know—ivory, cabled fisherman sweater. But it was just like the sweater didn’t have the juice.

[Music]

Rosin: I’m Hanna Rosin, and this is Radio Atlantic.

A comedian named Ellory Smith retweeted these two sweater pictures side by side, the one of Billy Crystal and the one of Ben Schwartz, writing, “The quality of sweaters has declined so greatly in the last twenty years that I think it genuinely necessitates a national conversation.” I 100 percent agree.

And the only person I want to have that conversation with is Amanda Mull, because she’ll be able to explain why a sweater is not just a sweater. It’s a window into so many of the problems of our modern consumer culture.

So, here we go.

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Rosin: Did you yourself go through a prolonged period of sweater disappointment?

Mull: You know, I moved to New York in 2011. I’m from the South. I’m from Atlanta, so I didn’t need any sweater-buying skills for the first 25 years of my life. I had thought about this, like, not a single time because, you know, you put on a hoodie and you keep it moving where I’m from.

But suddenly, I needed to figure out how to buy, like, a whole new cold-weather wardrobe, so I made a lot of mistakes, and I made a lot of sweater mistakes because I figured, you know: Just go to any of the retailers where I’m buying my other stuff and order some sweaters from them, and it’ll be fine.

It was not fine. I got a lot of very itchy, very plasticky sweaters. I got things that pilled up immediately, that just looked terrible, looked really cheap.

I felt like a baked potato wrapped in foil inside of them. I was steaming like a dumpling. I was unhappy. I was itchy. I looked like I was in, like, this weird plastic material. I hated it.

And I did this for years before I realized that it’s the materials. I need to be looking at the fabric labels. I need to be looking at what these sweaters are actually made out of and probably spending some more money and spending some more time looking for better things. But yeah, I screwed up in that way for the better part of a decade, I would say.

Rosin: Okay, so we have sweaters of yore and sweaters now. Can you walk us through how these come into the world differently?

Mull: When you look at Billy Crystal’s sweater, you can make a few assumptions about what’s going on with it. The first thing is it’s almost certainly fully wool.

What kind of wool, it’s impossible for me to say, but there is an almost 100 percent chance that what you’re looking at is a completely natural-fiber sweater.

And it’s also double knit, which is why it looks so much heftier. At the time, sweaters were much more likely to be made of not just natural fibers, but of 100 percent wool.

That is traditionally the material that sweaters have been made out of for, you know, hundreds of years. A sweater like that would almost certainly be made in a wool-producing country.

Rosin: Mm-hmm.

Mull: So it might have been made in the United States. It might have been made in Scotland, New Zealand, Ireland, one of the places in the world where a lot of sheep are raised, a lot of yarn is manufactured, and then sweaters are then made from that yarn. Because it was almost certainly sold in the United States, in the 1980s there were some import controls on what could be brought into the U.S. and sold as far as textiles go, which means it was almost certainly made in a relatively wealthy country, where garment workers are more likely to have significant tenure on the job, real skills training, good wages—things like that.

So it was probably made by someone who has a lot of experience making sweaters.

Rosin: Interesting.

Mull: By someone who has lots and lots of training, lots and lots of particular skills.

Rosin: So the yarn would be wool, and whoever created it would be someone with sweater skills.

Mull: Right. Making this kind of knitwear is a very, very highly skilled task. It wouldn’t just be a person overseeing the machine; it would be a person manipulating the machine to ensure that you get all of that really rich cabling and all of those details. You know, it takes a lot of yarn to make a sweater that robust.

Rosin: I’m kind of sweating listening to you. Like, I want to be falling into nostalgia with you, but what I’m actually thinking is, like, No, no. Like, I feel too hot and sweaty. So that’s the sweaters of yore. Then what happened?

Mull: Well, in 2005, a trade agreement called the Multifiber Arrangement expired. The provisions within that agreement had been sort of, like, being phased out by design over the course of, like, a decade.

But in 2005, it went away. And what that meant was that the United States had fewer import caps on textile products that were being brought in from developing nations, or less-wealthy nations. And that sort of, I mean, it ended the garment industry in the U.S. as we know it, basically, because what became possible was all these manufacturers and retailers to look for manufacturing overseas in far less-wealthy countries—countries that would allow them to, you know, release more pollution into the environment, that would sort of kowtow to their interests in various ways. You know, the United States is not a perfect country by any means, but there are basic protections on worker safety in the environment that make it more expensive to manufacture here.

So, suddenly, brands could move their manufacturing overseas. Retailers could source inventory from factories overseas that were charging far less. All of these financial incentives just changed apparel as we know it.

Rosin: This sounds like a monumental change, and yet the word Multifiber Arrangement is not something that anyone would stop and notice, even though from what you’re saying it’s completely upended our closets and our lives. Why?

Mull: This agreement was written to expire, and then when it expired, a lot changed about clothing in the United States. What it did, essentially, was placate the domestic garment industry with 30 years of protection but then guarantee that when that 30 years was up, you know, it would sort of be open season. So it got the garment industry to sort of sign off on their own eventual death.

Rosin: So 2005 is a critical year. What does the post-2005 period look like?

Mull: 2005 was a watershed moment, but it wasn’t as stark as it might have been if the protection provisions of the agreement hadn’t been designed to be phased out. But in 2005, it’s basically open season. That is the era where you get a lot of fast-fashion retailers really expanding their presence in the United States.

The first H&Ms start opening in the U.S. You get Forever 21 flourishing. You have this sort of moment when there’s this big rush into this new type of industry that can flourish in the United States, and that rush is built on sort of terrible clothing.

Rosin: Well, now you say terrible clothing. Do you mean terribly made clothing? Clothing with terrible fabrics? Because you could get a lot of trendy clothing cheaply.

Mull: When fast fashion comes to the U.S., it brings with it its sort of internal financial logic. What that means is their goal is to sell as much clothing as possible, and they need to create the prices that allow them to do that. And being able to move manufacturing overseas means that they can vastly reduce their labor costs and also use much, much cheaper materials.

Rosin: So we started with sheep and wool. What do we switch to?

Mull: In sweaters, what this means is you’re getting a lot of what is essentially plastic. That will show up on fabric labels as polyester or polyamide or acrylic. That’s what you’ll usually find in sweater weaves.

You also get what is basically rayon. And in sweater knits, you’re starting to see a lot more of viscose, which is a fiber derived from bamboo, but it’s derived in a way that is really, really deleterious to the environment in most circumstances, and that fabric can be manufactured in other countries with poor environmental restrictions on industry.

So you get a lot more of that material and a lot more plastic.

Rosin: You know, it’s funny: It’s not that I didn’t notice fast fashion—of course I have, and have bought many a thing from its demonic jaws—but somehow the sweater existed in a different category.

A sweater is such a significant thing. If I think sweater, I still think of a Billy Crystal, fisherman, thick sweater, even though I have not worn one or owned one in many, many years. That is what a sweater is. You just, we don’t classify sweater as disposable.

Mull: Right. And the basic designs of sweaters that you see have not changed much in the last, you know, 40 years. You still see cable knits. You still see turtlenecks. You still see the sort of fine-gauge knits more likely to be made from an ultra-soft wool, like a cashmere.

So, because they’ve visually changed less over time, I think that people don’t go into buying one expecting it to be disposable, because it’s still something that has the look and feel of a thing that should be able to be worn for 10 years.

Rosin: Right. Right. What you’re describing has been happening in a pretty rapid way for 20 years. Have we really not noticed that our sweaters were rapidly deteriorating for 20 years?

Mull: Well, I think people have noticed it, but the consumer system is sort of inherently individualistic, and people tend to approach problems that they encounter within the consumer system as something that they can sort of, like, MacGyver their way out of—or if they’re just better educated, or if they look harder, or if they find, like, the secret source for the good stuff, that this is a problem that they can solve. We don’t think about consumption and about clothing and about changes in materials as this sort of collective issue, but that’s really what it is.

So I think that because we are not trained to look for the sort of big, hidden system behind why we have the sweater options we have, it is hard for people to do that.

And it’s just hard to get the type of view on the system that you would need in order to understand what’s happening. Like, if you are sort of a sicko like me, you know, you do a lot of reading about this. You read academic stuff. You read books on the history of textiles. But this history is pretty well hidden.

And the fashion industry goes to great lengths to purposefully hide this type of understanding of how its products are created and how that has changed over time, because fashion marketing works best when you are just thinking about your own aesthetic and sensory experience of a garment.

So there’s a real, concerted effort on the part of the industry at large to encourage people not to put real thought into why suddenly the sweaters are, like, a little scratchier now.

Rosin: Yeah. Yeah. Oh, that makes so much sense. I would also say that probably we let it happen because there’s some ways that it’s better. Because laundry is easier. I can have a sense that I’m accessing a luxury item for cheaper. So there are ways in which it’s working for people.

Mull: Absolutely. I think that the fashion industry does a great job of sort of paying off consumers for not thinking about this stuff too hard.

It is fun to have, like, a zillion options when you get dressed in the morning or when you are packing for a vacation. Having this type of variety and this type of choice is something that in the past was only available to wealthy people and to celebrities, and getting to sort of star in our everyday life with our own custom wardrobe is fun. Putting on a cute outfit is fun. Buying a new outfit is fun. I love clothing. I totally get why people buy all of this stuff and why it’s just a little bit easier not to look too hard at the man behind the curtain.

There is not a lot of upside to people in looking into exactly where any of this stuff comes from, or why it is ill-fitting, or why the seams split so easily, or why there’s so much of it and there used to not be nearly as much. There’s not really a lot of personal upside to looking into that, except getting depressed.

[Music]

Rosin: After the break, Amanda will teach us what to look for if we absolutely need a new sweater. Back in a moment.

[Music]

Rosin: Before we climb out of the hole—because we will climb out of the hole—besides split seams, what are the other collective costs of this system for us, for people around the world?

Mull: The things that the consumer system obscures are largely bad, especially when it comes to fast fashion. Garment workers overseas work in generally terrible conditions. They work for very, very little money. A lot of them have very little control over their day-to-day lives. Some of them live in in dorms that are, you know, owned by their bosses. There’s very little ability to sort of, like, live a happy, independent, secure life if you’re a garment worker in most of the world. It is a really, really dark system underneath the surface in order to create all of this really, really inexpensive stuff.

You know, if a sweater costs $10, that savings is coming from somewhere, and it’s probably coming from the people in the system with the least power and the least ability to stand up for themselves.

Rosin: Right.

Mull: And then you also get a significant environmental impact from all of this. A lot of the countries that host these types of manufacturing outfits have fewer environmental protections.

So there is a ton of pollution that happens and a ton of human-rights abuses that happen on the front end, when things are being manufactured. And then you just end up at the other end of that manufacturing process with a lot of physical waste. In order for fast fashion to work, companies have to manufacture far more than they can reasonably sell to people, so you end up with a lot of excess clothing that gets dumped, usually in poor countries. There are, in particular, real problems with clothing waste being shipped to Ghana and Chile and then just dumped in these sort of vast piles of waste.

And the stuff we’re talking about here is stuff that was never sold. It was never used. It is pure front-to-back waste. That accounts for a lot of the textile waste in the world. But then also, fabric recycling is really, really difficult. And a lot of things ultimately just cannot be recycled, or it’s not cost effective to recycle them. So because buying habits are sort of decoupled from any actual need or want, people buy stuff that then doesn’t get worn or that gets worn once, and then it ends up being donated, and a huge proportion of that ends up just being wasted. It cannot be recycled.

So you’ve got more stuff for the great clothing-waste piles in these poorer countries that are just essentially a dumping ground for us. You’ve got plastics in waterways. You’ve got hazardous chemicals in waterways that are coming out of these garments that are just wasted. There’s a lot of waste and a lot of human suffering that comes out of this.

Rosin: I’m utterly paralyzed. I’m never going to buy anything again.

I don’t know exactly how spiritually to turn this shift, because everything you said was much more serious than the question I’m about to ask you.

But the reality is: It’s cold. Sometimes I might, maybe, still want to buy a sweater for my niece. Maybe. Or I might have a “friend” who wants to one day buy a sweater. (Not me. I’ll never buy anything again.) How do you MacGyver this?

Mull: There are still places out there where you can find 100-percent-wool sweaters made in factories in countries that have real protections for their garment workers, that are made by companies that care about this type of stuff. It’s a tall order to have to do all that research yourself and try to sort through this. It is, in a lot of situations, maybe impossible.

But sweaters, because they are so deeply tied to certain regions of the world and to long-standing garment traditions that are ongoing in those regions—if you look for sweaters that are made in Ireland, Scotland, or New Zealand, a lot of those are going to be made with real wool from sheep that were treated pretty well and by people that are skilled workers.

And those don’t have to be super expensive. A lot of those, you can have something like that for less than $200. And for a garment that you expect to last year after year after year—and to serve not just a fashion purpose, but a functional purpose in your wardrobe—part of this is just a mindset thing. If you let go of the idea that you need or want to have a new wardrobe every season, I think it’s easier to then go: Okay, I am going to buy one $150 fully wool sweater, and I am not going to get sucked in by the email sales and by Instagram ads and by all of these constant prompts that we receive to purchase additional stuff.

Everybody that I talked to for this story said that their favorite place to get really good, quality sweaters is through secondhand shopping. Because they’re secondhand, you can get a good price on them. You can pay the same amount for one of these that you would pay for a brand-new, plastic sweater in a store. And then you’re also not contributing to this larger issue of the constant cycle of new things that are being put into our physical world.

Rosin: I’m gonna put a Post-it note near my bed that says, “plastic sweater,” because I think if I’m ever tempted, that phrase “plastic sweater” will dissuade me from buying anything new.

I want to ask you about a couple of methods that, now that I’m talking to you, I have used but sound wrong. One thing is price, luxury—that does not necessarily, it sounds like, ensure that my sweater is not plastic.

Mull: Right. One of the most difficult things about the consumer system as we experience it now is that price is pretty much entirely decoupled from any sort of expectation you should have about the quality of an item or the item’s material composition.

Rosin: You say that so casually. That’s so crazy. Like, that is so confounding that you said it’s completely decoupled.

Mull: Right. You know, sometimes a really, really expensive thing is going to be really that much better than its less-expensive counterparts, but usually not. I don’t think there’s really any obvious correlation between the two anymore. It’s pretty much certain that if you’re buying a $20, brand-new sweater, what you’re getting is terrible quality. But there’s not any guarantee that if you’ve spent $3,000 on a sweater that it’s going to be markedly better.

Because the logic of fast fashion has infiltrated a lot of parts of the fashion industry, people expect clothing will look old—trend-wise, if not wear-wise, as far as quality goes—in six months.

They expect to move on. So there’s no real incentive for a lot of luxury brands to make their stuff to be substantially better quality than some of the much cheaper options.

Rosin: So you can’t rely on cost. Can you rely on tags? Like, can I just read the tag and see what it’s made of? Or are there euphemisms there that I might not catch?

Mull: The best thing that you can do is to learn what your fabric tags mean when you look on the inside of a garment. Wool means wool. Cotton means cotton. Linen means linen. Polyamide, polyester, acrylic—those all mean plastic. (Laughs.)

Rosin: Right. What about Mongolian wool? Like, I bought a sweater and it said, “100 percent Mongolian wool.” Is that just wool? Sometimes I’m afraid there’s some euphemism that I never heard of and that’s fake, and there are no Mongolian sheep—just in pictures. It doesn’t really exist.

Mull: Well, wool is sort of a catch-all term. It can come from a lot of different animals. So that level of detail is useful because it might tell you a little bit more about the texture of the garment or how it will look over time with wear. Different wools do have different physical properties, so that can be useful on that level. It doesn’t necessarily tell you anything about quality. But wool is always a good starting point to understanding what it is you’re looking at and what it is you can expect from that garment.

And knowing what the less-definitive words mean as well—viscose, rayon, modal—these types of fabrics are generally the bamboo-derived ones and, while technically a natural fiber, there’s a lot that goes into the creation of that that is not necessarily very good for the environment or for the people working on it.

So learning exactly what those terms mean, too, is useful, and you’ll see the same ones over and over again. Once you learn what all of this means, it is knowledge that you can take with you for the rest of your life and be pretty set when trying to make the most basic decisions about whether or not you want to buy something.

If you can get yourself out of that headspace that says that you need more stuff, that you are missing things, it’s a good idea for everybody to just slow down and go: Okay, I have five sweaters in my closet already. I have but one human body. I can only wear so many sweaters. Do I already have something that’s similar to this and that I just haven’t thought about in a while or that I just haven’t tried on with the new pair of pants that I got that might look great with it?

Making yourself aware of what you already own, and if it fits you, and how it feels on you, and how it might go with the things that you have already is good. Being familiar with your own wardrobe is good. And really, just the problematic behavior here—no matter where you’re getting your stuff—is just buying for the sake of buying.

[Music]

Rosin: This episode of Radio Atlantic was produced by Kevin Townsend. It was edited by Claudine Ebeid, fact-checked by Yvonne Kim, and engineered by Rob Smierciak. Claudine Ebeid is the executive producer for Atlantic Audio, and Andrea Valdez is our managing editor. I’m Hanna Rosin. Thank you for listening.

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It was a thrilling possibility. “Signs of Life Found in the Clouds Surrounding Venus,” one headline blared; another, “Aliens Were on Venus This Whole Time?!” It was also, it turned out, a false alarm. The phosphine not only wasn’t a signal of life, but probably wasn’t even there at all, a swing-and-a-miss of data interpretation. The clouds of Venus were still, as far as anyone knew, as uninhabited as they’d always seemed.

Scientists took the false alarm in stride. Back to the drawing board, they seemed to say, shrugging—or back to their telescopes at least. This is how science works, after all: gradually, in small steps, in announcements and skepticism and reconsideration of the data. It’s even harder when the subject of study is extraterrestrial. Venus is the closest possible home to alien life, but there’s no way to go and scoop a sample of its atmosphere to put under a telescope. The search for alien life is done remotely, by interpretation and inference. The suspected phosphine—considered a “biosignature” by astrophysicists, because phosphine on Earth is only ever abundant when it’s a product of life—wasn’t even observed directly. Instead, the researchers detected it by analyzing wavelengths of light that could hint at what molecules might be in Venus’s atmosphere. The researchers were searching for a sign of a sign of life. There was a lot of room for error.

The search for extraterrestrial life is not the kind that is likely to yield an aha moment—not in the sense that, with the tools currently available, scientists are going to look at data brought in from the cosmos and instantly declare, “Yes, this is life.” There are too many technical hurdles, too many variables that will need time to be sorted out. And even accounting for those issues, another obstacle exists—an enduring puzzle that tests the limits of science. The fact is, we still don’t know what life is.

Hold a rock next to a flower and you’re probably confident you know the difference. But since the days of Aristotle, scientists and philosophers have struggled to draw a precise line between what is living and what is not, often returning to criteria such as self-organization, metabolism, and reproduction but never finding a definition that includes, and excludes, all the right things. If you say life consumes fuel to sustain itself with energy, you risk including fire; if you demand the ability to reproduce, you exclude mules. NASA hasn’t been able to do better than a working definition: “Life is a self-sustaining chemical system capable of Darwinian evolution.” It’s a decent way to describe life on Earth, but it lacks practical application. If humans found something on another planet that seemed to be alive, how much time would we have to sit around and wait for it to evolve?

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In recent years, the potential rewards of unlocking a theory of life have captivated a clutch of researchers from a diverse set of disciplines. “There are certain things in life that seem very hard to explain,” Sara Imari Walker, a physicist at Arizona State University who has been at the vanguard of this work, told me. “If you scratch under the surface, I think there is some structure that suggests formalization and mathematical laws.” It has long been presumed that although theories can explain physics and chemistry, biology is too messy, too contingent, to be boiled down to math and formulas. In 1997, the renowned biologist Ernst Mayr wrote that although the molecules that compose living organisms obey the laws of physics just as all molecules do, “organisms are fundamentally different from inert matter.” There is a threshold that matter can cross, beyond which the laws of physics do not explain or predict what happens; on the other side of that threshold is life.

But Walker doesn’t think about life as a biologist—or an astrobiologist—does. When she talks about signs of life, she doesn’t talk about carbon, or water, or RNA, or phosphine. She reaches for different examples: a cup, a cellphone, a chair. These objects are not alive, of course, but they’re clearly products of life. In Walker’s view, this is because of their complexity. Life brings complexity into the universe, she says, in its own being and in its products, because it has memory: in DNA, in repeating molecular reactions, in the instructions for making a chair.  

Lee Cronin, a chemistry professor at the University of Glasgow and Walker’s main collaborator, told me that when Walker first explained to him her ideas for a theory of life, “I was like, ‘I have no clue what you’re talking about. But it feels like we are saying something super similar.’” Cronin studies the origin of life, also a major interest of Walker’s, and it turned out that, when expressed in math, their ideas were essentially the same. They had both zeroed in on complexity as a hallmark of life. Cronin is devising a way to systematize and measure complexity, which he calls Assembly Theory. He measures the complexity of an object—say, a molecule—by calculating the number of steps necessary to put the object’s smallest building blocks together in that certain way. His lab has found, for example, when testing a wide range of molecules, that those with an “assembly number” above 15 were exclusively the products of life. Life makes some simpler molecules, too, but only life seems to make molecules that are so complex.

No one expects to find an alien cellphone in Mars’s Jezero Crater. But Walker’s whole notion is that it’s not only theoretically possible but genuinely achievable to identify something smaller—much smaller—that still nonetheless simply must be the result of life. The model would, in a sense, function like biosignatures as an indication of life that could be searched for. But it would drastically improve and expand the targets. Walker would use the theory to predict what life on a given planet might look like. It would require knowing a lot about the planet—information we might have about Venus, but not yet about a distant exoplanet—but, crucially, would not depend at all on how life on Earth works, what life on Earth might do with those materials. Without the ability to divorce the search for alien life from the example of life we know, Walker thinks, a search is almost pointless. “Any small fluctuations in simple chemistry can actually drive you down really radically different evolutionary pathways,” she told me. “I can’t imagine [life] inventing the same biochemistry on two worlds.”

Devising a universal theory for life is an ambitious project, to say the least. The scientists I’ve spoken with who are leading the search for biosignatures tend to welcome Walker’s unconventional approach, on the grounds that the more tools available, the merrier. Even so, no one is abandoning their search in the hopes that humanity will soon solve the mystery of life. After all, finding any examples of alien life—Earthlike or not, by whatever means possible—would radically advance our ability to understand the phenomenon.

Walker’s approach is grounded in the work of, among others, the philosopher of science Carol Cleland, who wrote The Quest for a Universal Theory of Life. But Cleland doesn’t share Walker’s ambitions that a theory may be within reach; instead she warns that any theory of life, just like a definition, cannot be constrained by the one example of life we currently know. “It’s a mistake to start theorizing on the basis of a single example, even if you’re trying hard not to be Earth-centric. Because you’re going to be Earth-centric,” Cleland told me. In other words, until we find other examples of life, we won’t have enough data from which to devise a theory. Abstracting away from Earthliness isn’t a way to be agnostic, Cleland argues. It’s a way to be too abstract.

It’s a knot easy to get tied up in: We don’t have a theory of life to guide the search for extraterrestrials, but we need to find extraterrestrial life before we can understand life with a theory. Instead of provincially looking for life as we know it, Cleland calls for a more flexible search guided by what she calls “tentative criteria.” Such a search would have a sense of what we’re looking for, but also be open to anomalies that challenge our preconceptions, detections that aren’t life as we expected but aren’t familiar not-life either—neither a flower nor a rock. It’s unsatisfying if you want a firm answer or a quick one, but it speaks to the hope that exploration and discovery might truly expand our understanding of the cosmos and our own world.

Cleland’s approach ends up sounding much like a lot of the work being done hunting for biosignatures today. A true discovery of phosphine in the clouds of Venus would be an anomaly for sure, and absolutely challenge preconceptions about the kinds of chemistry happening in those clouds. Other work in the field seeks similar surprises. The astrobiologist Kimberley Warren-Rhodes studies life on Earth that lives at the borders of known habitability, such as in Chile’s Atacama Desert. The point of her experiments is to better understand how life might persist—and how it might be found—on Mars. “Biology follows some rules,” she told me. The more of those rules you observe, the better sense you have of where to look on other worlds. In this light, the most immediate concern in our search for extraterrestrial life might be less that we only know about life on Earth, and more that we don’t even know that much about life on Earth in the first place. “I would say we understand about 5 percent,” Warren-Rhodes estimates of our cumulative knowledge. N=1 is a problem, and we might be at more like n=.05.

When I talk with people about a theory of life, which lately is my best attempt at small talk, I reach for the theory of gravity as a familiar parallel. Someone might ask, “Okay, so in terms of gravity, where are we in terms of our understanding of life? Like, Newton?” Further back, further back, I say. Walker compares us to pre-Copernican astronomers, reliant on epicycles, little orbits within orbits, to make sense of the motion we observe in the sky. Cleland has put it in terms of chemistry, in which case we’re alchemists, not even true chemists yet. We understand so little, and we think we’re ready to find other life?

Maybe we’ll never be ready. Yet how could we not search? Right now, the James Webb Space Telescope is peering into exoplanet atmospheres for spectral signatures. The Perseverance rover is bottling up soil samples on Mars for a future mission to bring to Earth to study. How could we not trawl the cosmos for anything that could help us understand our place in it, our kinship lines, and how this life, on Earth, came to be? And so we try. We scour other worlds, scan their clouds. And scratch beneath the surface, for the theory that might explain it all in equation and abstraction, to see the deeper truth beneath what we can see.