Who out there knows that butterflies are scented? Their aroma can be that of flowers like honeysuckle or jasmine, herbs and spices like lemon verbena or cinnamon, or confections like vanilla or chocolate, depending on the species. It can also be unpleasant, like vinegar, or urine. According to Avery Gilbert, author of What the Nose Knows, scented butterflies are neither exotic nor rare. While field guides do not say so, Gilbert notes that butterflies can easily be caught, sniffed, and released unharmed. What a captivating pursuit!
With my recent article on body odor, and the heat of summer causing lots of seasonally assertive odors, questions about the power of scent have stuck in my mind. So I turned to an expert: Gilbert’s new book examines why the sense of smell is so underappreciated, and why it should be valued at least as much as seeing or hearing.
History is largely to blame for smell’s poor profile. Linnaeus, the great classifier, invented the first scientific classification of smells in 1752, but it was limited to the therapeutic effects of different plant odors. Darwin thought smell was important to our early ancestors, but of only minimal service to modern man. Freud believed that the smell became obsolete when humans started walking upright and no longer had their noses close to the ground. He asserted that repression of smell led to the repression of wild sexual impulses, which was a vital condition of civilization. Such surprising “intellectual indifference to smells” might be explained by the fact that Freud’s nose was a “medical disaster zone,” as Gilbert puts it, from cigar smoking and repeated sinus infections.
In short, Freud probably suffered from a condition called hyposmia, which is a significantly reduced ability to smell and detect odors. It is estimated that up to two percent of the population have reduced or incomplete smell sensitivity as a result of events like severe colds and sinus infections, or head injury that causes damage to the first cranial nerve. Imagine life without the ability to detect smoke from a fire, toxic fumes, or spoiled food, not to mention the potential effects on personal hygiene.
Human olfactory talent is informed by our sensitivity to and awareness of smells, and also by our ability to identify and discriminate among them. Here is where our brains carry some of the responsibility for why we underestimate smell. Scientific research has found that while humans can detect thousands upon thousands of distinct scents, our brains quickly reduce that sensitivity. “We have limited ability to think about smells analytically,” according to Gilbert, and this means that our brains reduce the massive variety of smells in the world to a “manageable handful” of about a dozen odor classes — think minty, citrusy, woody, fruity, skunky, sulfuric, and so on. This simplification has made it next to impossible for scientists to count just how many smells there actually are in the world.
The difficulty inherent in describing scent is also perhaps why, in a publishing world filled with wine critics and even cigar reviewers, there are so few people writing about perfume. Gilbert calls this the “verbal barrier,” and describes how perfectly communicative people become tongue-tied trying to describe a scent. When exposed to a lemony odor, for instance, people say it smells like lemon. Not any particular kind of lemon, just lemon.
It is not that we have a limited vocabulary for smells, says Gilbert, harkening to our endless adjectives for smelly things and to brands with iconic scents like Vicks VapoRub and Play-Doh. Rather it is more a cognitive problem, he says: “The words are there, but we have a hard time getting to them.” This “tip-of-the-nose” phenomenon occurs commonly when humans are given random odor tests under laboratory conditions.
With scent, context is of utmost importance. The ability to portray scent in a believable and resonant way requires not only odor awareness but also empathy for how others experience smell and imagination. French novelist Emile Zola referenced smells abundantly and evocatively in his books. He had a strong memory for odors and liked to compare and analyze odors, yet when a panel of physicians and psychologists tested him later in life, they found that his smell sensitivity was a bit below average. The panel concluded, Gilbert says, “that Zola’s fictional smells were more the result of a supple olfactory imagination than of nose-skills.”
But words cannot recapture a scent once it is gone and forgotten. Gilbert wonders about the memories and feelings that we’re missing when a specific odor is no longer there to smell. A long-forgotten odor can illuminate a specific memory or cause us to relive a bygone moment. Oliver Wendell Holmes, the 19th-century American writer and physician, recalled feeling overcome by the “odorous echo of a score of dead summers” upon opening the pantry in his childhood house.
An entire smellscape can fade away with the changing of times and the closing of a beloved places. H.L. Mencken, for instance, could never re-experience today the “cool, refreshing scent of a good saloon on a hot Summer day, with its delicate overtones of mint, cloves, hops, Angostura bitters, horse-radish, Blutwurst and Kartoffelsalat” that he experienced when accompanying his cigar-manufacturer father on pre-Prohibition sales trips. Gilbert includes a list of endangered smellscapes, like the school-time smell of paper fresh from the ditto machine, the odor of Wite-Out from typewriting class, and even the special scent Grandma’s kitchen imbued with simmering tomato sauce, home-brewed coffee, and fresh-baked fruit pies.
Sometimes, such smells are not particularly popular. He notes the efforts of the National Steinbeck Center in Salinas, Calif., to preserve the author’s fictional smellscapes. An interactive exhibit that matches smells to different Steinbeck books no longer emits that sardine scent of Cannery Row after visitors complained that something in the museum was rotting.
Whether pleasant or not, it seems high time to preserve today’s smells in a vault in the same way that scientists are preserving plant seeds to protect them from the world’s wide-ranging threats. Gilbert notes how Andy Warhol created something of the sort: He wore a cologne until it built up strong emotional connections, and then he would retire it to his personal smell museum, in essence locking in the memories associated with the cologne. Many other smells are not so easy to revisit. Once a smell becomes extinct, it takes extraordinary effort to re-create it, if it is even possible at all, says Gilbert.
Knowing this makes me want to run outside, capture a butterfly, and inhale its scent. • 23 June 2008
REFERENCE: What the Nose Knows: The Science of Scent in Everyday Life. By Avery Gilbert. Crown Publishers: New York. 2008.