In 2008 Luca Turin, a European biochemist who’d done groundbreaking research on how olfaction works, joined forces with Tania Sanchez, a thirtyish American, to produce an English edition of his cult hit French perfume guide. The result, their Perfumes: The Guide, has a wide readership among people who admire good perfume, but it deserves a wider one among people who admire good criticism of any kind. I found it in the “fashion” section of a classy bookstore, and in retrospect this seems like finding Madame Bovary shelved with the historical romances.

Unfortunately, though, Perfumes has the side effect of making the reader—well, this reader—embark immediately on the kind of quest that leads her to a lot of esoteric corners of the internet and shoddy midtown shops. But more on that later.

I picked up Perfumes on a whim, expecting standard women’s magazine perfume writing: imaginary fruits and lavish adjectives, nonsense marketing descriptions bracketed with pseudoscientific junk about how smells awaken our reptilian base nature. Sanchez seems to have anticipated this concern. “Smell psychologists and the uncritical journalists who love them get a lot of mileage out of calling smell the most primitive sense. But as with all of the work of evolutionary psychologists, the conclusions that support our desires and reinforce our prejudices are those of which we should be most wary,” she writes.

I read the rest of that page standing up in the store and finished the introduction on line at the cash register.

Sanchez goes on to debunk any and all fixed ideas anyone might have had about perfume in an economical four pages. She describes the ways the industry has discouraged serious perfume criticism, from concealing the identities of fragrances’ authors to lying about formulas and content. She explains why this is a golden age of perfume criticism (the Internet). She dismisses the notion that talking about our pleasures ruins them. “The fact is,” she announces in closing, “this stuff is worth loving. As with the tawdriest pop melody, there is a base pleasure in perfume, in just about any perfume, even the cheapest and most starved of ideas, that is better than no perfume at all.”

And then the real fun begins: the reviews. Most writers describe smells so vaguely, badly, or just plain inaccurately that the sheer pleasure of reading a detailed, precise description of a smell comes as a shock. Turin and Sanchez evoke the olfactory equivalent of an imagined image. Sometimes their metaphors are visual: a sheer scent is like a richer scent “seen through frosted glass.” Sometimes they describe smells in terms of sound: a disappointing masculine is “flat, in the musical sense” while oppressive feminine florals are often “hissy” “screechy” or “nasal-voiced.” Sanchez leans more towards narrative than Turin: Ormonde Woman “has the haunting, outdoors witchiness of tall pines leaning into the night—a bitter oakmoss inkiness, a dry cedar crackle, and a low, delicious, pleading sweet amber, like the call of a faraway candy house.” Turin is more likely to imagine a fragrance embodied as a human, usually as a female: “Catherine Deneuve is speaking fluent Arabic” in Jubilation 25, Equistrius is “as effortlessly classy as a pale young girl with violet eyes,” while Frangipane is “blandly pretty and just interesting enough to stand out without disturbing anyone, like a young socialite who takes a Latin dance course and ever after is known as the daring one in her set.”

Neither writer can resist a joke, and some of the one-star reviews are the book’s best. Sanchez, once a prolific fragrance blogger, is conversant in both the highly specific vocabulary of perfume (“drydown,” “gourmand,” unpronounceable names of molecules, etc) and the highly specific argot of the Internet. She deploys the latter sparingly but with great flair. Her review of cK In2 U His reads, in its entirety: “IM IN YR BOTTLE, BORIN YR GF.” At some point the reader begins to wonder: how did this late-middle-aged Continental scientist and this young sometime blogger ever come to write this book together?

A quick search uncovers that Sanchez has been living in Greece, where Turin also lives. A Guardian article from 2008 reveals that the two have “recently married.” Sanchez is quoted saying that a correspondence led to artistic collaboration, which led to romance. It’s hard to imagine anything more thrilling: a meeting of the minds, and, not incidentally, noses. In an essay on feminine perfumes in The Guide, Sanchez cautions against buying into the idea that perfume is a tool of seduction, saying that the only smell she knows of that is irresistible to men is bacon. But while perfume itself may not be alluring, the idea of perfume obviously is: Turin and Sanchez’s love story is proof.

Another of Perfumes’ revelations was the idea of perfume authorship. Turin and Sanchez explain particular historical and contemporary perfumers’ signature styles and the spread of their influence. When I learned that the two perfumes I’d ever had committed long-term relationships with—Eau Parfumée au Thé Vert and Un Jardin en Meditaranée—were the work of the same guy, I felt the way someone might feel on learning that her two favorite novels had the same editor. In this case, the “editor” was Jean Claude Elléna.

Before reading this book, I might have described these two scents as “green,” or “light” or “summery” or “plant-like.” But now I have a new arsenal of descriptive terms. Conjuring Thé Vert, the smell of my early college years, in my mind’s nose, I get an impression of attempted sophistication: smoky, powdery tea, tempered by a just a hint of Bath and Body Worksish fruit.

The more recent Elléna composition on my dresser, Un Jardin en Meditaranée, lured me in with a smell that, thanks to The Guide, I can identify as tomato stem: that great summery garden thing. But I found myself agreeing with Turin: the drydown (the perfume’s final stages) is “banal,” as the intriguing salty, vegetal smell the perfume presents in the showroom fades into a generic sharp greenness.

“You’ll use that stuff til it’s used up!” my budget-minded better half admonished me when he heard I was thinking of spending money on something as frivolous as a new smell. But how could I content myself with anything less than a perfect perfume, now that I knew there was an art to this stuff? The quest to find a perfume that could be one’s signature scent is a lot like any other quest for a “true self”—self-indulgent, quixotic, potentially expensive. Luckily perfume samples, like dreams, are free.

I began in Sephora—maybe the worst Sephora in the world, or at least in Manhattan. You know: the one on 34th Street across the street from Macy’s. The Guide advised me to smell some things—no more than ten—then walk away, coming back if anything remained compelling hours later. I thought I’d also take the opportunity to refresh my memory about every perfume I’d admired in my youth, as well as some of the ones The Guide raved about, to see if I could understand what it was about Shalimar that sent the authors into the throes of multi-page rapture.

This mission felt weird, though, and slightly illicit. No one else in that rush-hour Sephora was standing with a scent strip under her nose, lost in a reverie of unnameable associations. The perfume section seemed like an afterthought in a store full of women painting their own and each other’s faces; the men’s fragrance section was especially forlorn, in a corner behind the registers. In less than twenty minutes I’d accumulated ten or so scent strips that I shoved deep into my coat pockets, and then I left, feeling like I’d shoplifted something. On the subway platform I immediately dug them out again to test my recall. Yes, there was Shalimar: the familiar smell of the older lady sitting next to you in an overheated Broadway theater. I can’t quibble with The Guide about its formal beauty, but I never want to smell it again. I also snagged a strip of Jean Paul Gaultier Parfum, which the guide disdains as prime example of packaging (its wonderful Blonde Ambition corset-shaped bottle) trumping content. But I’ll always associate it with a middle-school trip to Paris that featured a free-range amble through the Galleries Lafayette, where I bought electric-blue eyeliner that smelled like greasepaint. “Canned sections of mandarin oranges in syrup” is the nicest thing Turin has to say about it.

I also got a strip of Thé Vert, to confirm that it wasn’t The One, and of course it wasn’t, but just a faint hit of it brought back college-era memories (mostly bad).

One of the cheap perfumes The Guide rhapsodizes about is Tommy Girl, and despite its late-nineties near ubiquity, I didn’t have any clear memory of ever having smelled it. It wasn’t on Sephora’s shelves for some reason (ousted by Justin Bieber or Hello Kitty’s new scents perhaps). So the next day, finding myself passing a Perfumania discount perfume store in the same dismal Midtown strip, I availed myself of the opportunity to smell it. I noticed a couple of things simultaneously. #1: It certainly did smell, as the Guide had promised, like a boiling samovar full of floral, interesting tea. But it was also familiar, and not because I’ve spent so much time around samovars. It reminded me of someone I’d known, someone specific—I didn’t immediately know who, but it was hers, and I could no more wear it than I could show up at her job tomorrow in her clothes.

I gave my nose a break for the next couple of days, but later that week I found myself having lunch a few blocks from the Williamsburg headquarters of CB I Hate Perfume. The weather was cold but damp, the frustrating kind of winter day where seven degrees makes the difference between a potential winter wonderland and a chill that gets in your clothes and won’t leave. I was wearing a big pile of wooly outerwear and looked stupid in it, so I was hesitant to enter the Gallery, which is clean, white and tiny. It was also, at that moment, empty. Retail conversations make me shy with their falseness and politely almost-hidden agendas. I’m so susceptible to guilt that I’ll sometimes make a purchase in order to avoid feeling like I’ve wasted someone’s time. I almost kept walking, but at the last moment I turned, rang the buzzer, entered.

The first thing that caught my eye was the rack of little bottles containing smells in the “Green” category. I felt more at home immediately, surrounded by those vials lemon leaf, galbanum, leaf (sappy), and lettuce (butter crunch). An amiable bearded, be-earringed boy in his early twenties with the faintest hint of a Southern accent appeared and I surprised myself by having incredibly specific requests for him. “I have smelled Smoky Tobacco and I like it, but I wonder if there’s anything like it that’s lighter—less like pipe tobacco and more like the smell of tobacco leaves drying in a barn.” Minutes later, the salesboy and I were busy unscrewing lots of little bottles, into which he dipped testers and then carefully, ritualistically anointed the backs of my hands (“they’re easier to wash off than wrists”). After the first six or so, I felt like my senses were getting fatigued, and he advised me to take a big whiff of my own clothes, which worked.

My favorites of the accords were Fireplace—its smokiness is exactly that of my grandparents’ living room during winter holiday celebrations—and Hay, which has an addictive clean sunny quality with just the slightest hint of healthy fermentation. There are hundreds of accords, and they range from Roast Beef to Nail Polish to Leather Baseball Glove. But I left without buying any of them and walked off north in a cloud of mixed smells, vowing to go back for Hay as soon as I had a little more cash.

As I made my way up Nassau Avenue I thought about how much I want Turin and Sanchez to bring their expert noses and uniquely brilliant brains to bear on ordinary smells, not just perfumes. How would they describe Greenpoint’s signature funk, shifting day to day depending on whether the wind is coming off the river or from the direction of the waste treatment plant? It’s also infused with the porcine stink on the sidewalk outside a Polish butcher shop, the incense filtering out from a church, the inexplicable bergamot cloud that hovers somewhere near North 11th and Wythe. I noticed these smells in a newly descriptive way, as if some seismic shift in my perceptive apparatus had occurred. It had been a while since I’d had occasion to remember that a book can have this effect

I haven’t found my signature scent yet but, per Turin and Sanchez, that kind of pointlessness is perfume’s point. It doesn’t feed us or shelter us or provide us with warmth. “It decorates the day,” says Sanchez, and though that sounds cheesy out of context, I hear it in my mind occasionally; her criticism has a pleasant way of lingering, like that, in the air.

Emily Gould is the author of And The Heart Says Whatever and the founder of Emily Books.