End-of-the year “notable” or “best” book lists usually slide by me, an interesting but distant phenomenon. I sometimes use them for their expressed purpose, as a gift-giving or reading guide, but for the most part, I skim and forget them. But this year, when a friend’s book of essays—Elena Passarello’s Animals Strike Curious Poses—made one of these lists, I found myself turning to them with a critical eye.

Robert E. Belknap, author of The List: The Uses and Pleasures of Cataloguing, writes that lists “grow by the will of the compiler . . . When a writer creates a list, he or she makes choices of inclusion or exclusion based on some desired criteria.” Thinking about criteria, I wondered: Why does Elena’s book of inventive essays sit next to books like World Without Mind: The Existential Threat of Big Tech and The Evangelicals: The Struggle to Shape America, which seem so obviously in a different category? And beyond whether a list did or did not include a book I loved, can these lists tell us something about the state of the literary world?

While every publication does its year-end book roundup a bit differently, they almost all start with a simple, categorical division between fiction and nonfiction. The Washington Post lists 50 notable books of fiction and nonfiction. The New York Times also presents 50 notable books in each of two categories, “Fiction & Poetry” and “Nonfiction,” though the list contains only three books of poetry. The Los Angeles Times’ best books list makes the same essential division with fewer titles: 19 fiction and 17 nonfiction. Specialty lists exist—Rolling Stone covers the year’s best music books, Seventeen lists YA books, NPR’s Science Friday gives us science books, and Smithsonian Magazine has history—but the fiction/nonfiction divide is by far the most prevalent, including in Quartz’s master best-of list, which combines 21 lists into one.

Between these two categories, markedly different descriptive language is used. For example, in the NYT list, adjectives used to describe fiction books speak to their effect on a reader—they are “haunting,” “stunning,” “fascinating,” and “magnificently funny”—or the list writer’s assessment of the book’s literary merit—books are “intricate,” “bold,” “masterly,” and “steadfastly literary.” Nonfiction books, on the other hand, are mostly described by what they do—a book “tells the story,” “argues,” “uncovers a policy,” or “writes about the impact.” When praise is given to a nonfiction book, it is based on the writer’s handling of information. They may have produced “a fair-minded” or “enthralling and essential” history, an “absorbing retelling,” “erudite historical case studies,” or a “vibrant, detailed chronicle.” At best, the prose might be deemed “compulsively readable.”

These language differences point to an underlying value system in which fiction is considered an art form, to be judged on its literary merit, while nonfiction is viewed as a source of information, judged for how effectively it conveys facts and research.

“On the whole, year-end lists tell us that the ‘best’ fiction is the ‘literary’ kind, while the ‘best’ nonfiction is the informational kind.”

It follows that books of literary fiction and informational nonfiction would more likely make a year-end best-of list. Reviewing The New York Times, Washington Post, and the Los Angeles Times lists, I found this to be true. The nonfiction book category is dominated by books that promise information, most often histories and biographies. Meanwhile, fiction lists are dominated by what is usually called “literary” fiction, a term that is defined not so much by what it is as what it isn’t—fantasy, mystery, science fiction, romance novels, and other so-called “genre” fiction. While many publications produce year-end round-ups for certain genres—the NYT collects 2017’s best crime books, for example—these lists are clearly separated from the best-books lists, which contain few genre fiction entries.

Crossovers exist—I’m thinking of nonfiction books like Eula Biss’s On Immunity, which earned a spot on the a 2014 NYT top-ten best books list, where it was called “spellbinding” and “ferociously intelligent.” The book, which explores our collective vaccination anxiety through lenses of language and personal experience, manages to present information while being recognized first as a work of literature. But on the whole, year-end lists tell us that the “best” fiction is the “literary” kind, while the “best” nonfiction is the informational kind.

Once upon a time, year-end best-of book lists had space for many more kinds of books. The 1994 New York Times notable list had 14 categories: Art, Music, and Popular Culture, Autobiography & Biography, Children, Crime, Essays, Letters & Criticism, Fiction, History, Poetry, Popular Culture, Religion & Philosophy, Science Fiction, Science, Medicine & Psychology, Sports, and Travel, Nature & Adventure. I was unable to find a 1995 list in the paper’s online archive, but by 1996, there were only five categories: Fiction, Poetry, Nonfiction, Mysteries, and Science Fiction. This move collapsed many types of adult nonfiction into one blanket category. In 1997, the list shifted slightly to combine fiction with poetry and add children’s books, and that set of five categories continued until 2004, when the list took its current, two-category form: Fiction & Poetry and Nonfiction.

Why the condensation? I asked, but NYT Books Review editor Pamela Paul was preparing to be out of office and did not have time to respond. I was able to reach Los Angeles Times books editor Carolyn Kellogg, who said that in her tenure (she’s been working at the paper for close to a decade), the paper’s year-end books lists had been framed as a holiday guide until this year, when she thought, “let’s just call it like it is.” The result is the paper’s first year-end best books list since 1931.

For Kellogg, having two rather than a dozen book categories is a practicality. “I like the idea of having really big buckets so you have the room to slide in something like a graphic novel without creating a graphic books list,” she said. “The bigger the bucket is the broader you can go.”

I understand the logic of practicality, and I wonder whether category cutbacks at the NYT had something to do with reductions in print page space: when the paper chopped its category count, it also reduced the total number of books listed. So perhaps there are no longer enough people or time to curate all of these different categories. Or perhaps reader taste, or publishing trends, or other industry insider knowledge to which I’m not privy has driven category changes. Or perhaps there simply aren’t enough notable books of essays, pop culture, or science each year to warrant separate categories.

Beyond the practical, I can see an argument for the philosophical benefit of this category collapse. If genre fiction has traditionally garnered less literary respect than literary fiction, then placing the two alongside each other on the main best-of books list implies a transcendence of the genre fiction label and an attainment of parity. But my reading of the lists showed that this kind of crossover is rare, and for nonfiction, the line of logic breaks down. If the year’s best nonfiction means the most informational nonfiction, then placement in this list elevates literary nonfiction to a place it never aspired to be, without recognition as a work of artistic value.

So, would I prefer a system of more nuanced categorization? I’m not sure. The NYT older lists look a lot more like library book classification systems, and there are problems with these, too. U.S. libraries almost always follow either the Dewey Decimal Classification (DDC) system, typically used in public and K-12 school libraries, or the Library of Congress Classification (LCC) system, used in most large college, university, and research libraries.

In libraries, these classification systems are practical tools that tell you were to find a book on the shelves. They operate using a set of main headings or classes—in the U.S., the top-level Dewey classes are:

000 – Computer Science, Information, and General Works

100 – Philosophy and Psychology

200 – Religion

300 – Social Sciences

400 – Language

500 – Science

600 – Technology

700 – Arts and Recreation

800 – Literature

900 – History and Geography

Additional numbers are added in the tens, ones, and decimal places to create increasing levels of specificity. For example, David Grann’s Killers of the Flower Moon: The Osage Murders and the Birth of the FBI, a book that appears on all three of the year-end lists I examined, is classified by my local public library with a number of 976: 900 for History and Geography, 970 for History of North America, and 976 for South Central United States.

Public libraries classify everything from reference manuals to philosophical treatises, literary essays, and poetry, with one giant exception: fiction. Dewey has a class for fiction under Literature in the 800s, but almost no public libraries use it. Instead, they give fiction its own shelves which are alphabetized by author last name, effectively creating two major library categories that mirror those in today’s year-end list: fiction and nonfiction.

I spoke with Felicia Ugden, who runs cataloguing for my local library in Corvallis, OR, to better understand this decision. Ugden oversees the library’s assignment of call numbers. She has been working in libraries since the late 1970s and said she’s never seen a public library that “classed” fiction the same way they do the rest of the books. She gave me an example to illustrate why: Say you wanted to read Les Miserables, Victor Hugo’s classic French novel, in English. To find it in the Dewey system, you would need to know that it was originally published in French, and that even the English translation would be classified under 840 for French literature. Simply put, most library visitors would need to be much better informed.

“Here in the public library we tend to think, where is someone going to look for it?” she said. “We want browsers to find it. We want things to check out.” By contrast, she said, academic libraries using the LCC system typically classify all books, because they assume research is a searcher’s primary intent.

I asked Ugden, what about those works of nonfiction that readers approach more like they do fiction? Things like memoir, where readers might know the author’s name better than its topic, or essays, which might cover many topics? She laughed, and said: “I think you’re making an argument that those things should be unclassed, too, and I kind of like it.” She told me that literary nonfiction like this can be hard to class, so many of these books end up in 921, for biography, though the Dewey system has actually stopped using this number in its more recent versions. Other times, if they are judged to be works of “imagination,” the books go in the 800s for literature. But most libraries, Ugden told me, still class nonfiction works by their subject. Sometimes, this means that books get classified differently depending on their library. For example, the Corvallis library files Roxane Gay’s memoir Hunger, which appears on the Los Angeles Times’ list, under that old biography number 921, while the library I used when I lived in Washington, D.C. files it in 306: 300 for Social Sciences, and 306 for Culture and Institutions.

“In public libraries, subject matter—information—is prioritized over form, which can leave inventive literary works withering in the stacks next to dry reference material.”

The result of this classification system is that the nonfiction winds up, in many ways, less browseable than fiction. I went to the library a couple weeks ago for Meghan Daum’s book of essays The Unspeakable and Other Subjects of Discussion and found the book filed in “Adult Nonfiction” under 814—800 for Literature and Poetry, 814 for American Essays in English. While I was there, I figured I would look for other, similar books. I found some, but I mostly found things that seemed completely unrelated, including a biography of Gertrude Stein and several volumes of Representative American Speeches.

The same problem can be found at bookstores. Not too long ago, I found Maggie Nelson’s Argonauts and Bluets across the store from one another. And if I wanted to buy three nonfiction books from these best-of lists—say, Grann’s Killers of the Flower Moon, Gay’s Hunger, and Ta-Nehisi Coates’ We Were Eight Years in Power—from Powell’s bookstore in Portland, I’d have to visit the yellow room for crime, and then go up a floor to the red room for African American studies and gender studies. But if I just wanted fiction, I could stay on the main floor in the blue room, for literature, and find them listed by author last name.

What to do about all of this? I’ll admit I’m not entirely sure. Shaun Usher, author of Lists of Note, told The Guardian, “Human beings love lists, because they create a sense of order in a chaotic world.” Beneath his statement lies, of course, another truth: any sense of order is false. No list, no order, can correctly mimic a chaotic reality. Still, we can always try to get closer.

Right now, public libraries and year-end book lists share the same problem, though for different reasons. In public libraries, subject matter—information—is prioritized over form, which can leave inventive literary works withering in the stacks next to dry reference material. Current year-end lists might seem to solve this problem. In eliminating sub-categorization of nonfiction, they treat it the same way libraries treat fiction: all books, regardless of subject, are presented in order of author name or title. Both fiction and nonfiction are “unclassed.” But a close look at these lists reveals the different value systems; the lists privilege literary fiction and informational nonfiction. Again, works of literary nonfiction struggle to find a place.

Perhaps it is nostalgia, but given the alternatives, I see something appealing in those older, multi-category year-end best-of lists. Of course, the categories would inevitably be inadequate. But more categories would forcibly overcome at least one level of the bias in current year-end lists. It becomes much more difficult to have a list composed mostly of histories and biographies if you’re also asked to identify the year’s best science, art, and travel books, and the existence of more categories seems to by default imply a more expansive definition of what is considered literary.

Without more in-depth examination of the language and content of the past lists, I can’t tell for certain if these thoughts bear out. Plus, I still wonder—how exactly would we find the literary nonfiction? Essays? A new, to-be-determined category? Shall we make use of that ill-fitting coat of a label, “creative nonfiction”? (I say: please, no.) Or maybe we should use the label I’ve been using, mostly for lack of something better, “literary nonfiction”? Maybe in this difficulty to classify lies some secret strength, speaking to the form’s rarity?

I don’t have these answers. I’d like to keep thinking about the questions. And of course, in the end, I have to agree with my librarian, who always gets the big things right: “I don’t believe in the perfect place,” Felicia Ugden said. “You have to decide for yourself where it makes sense.”