The Poetics of Smell as a Mode of Knowledge
By Maria Popova
On a recent train ride, my travel companion pulled two small clementines out of her bag and began peeling them. Instantly, a flood of associations rushed in uninvited — clementines like the many winter holidays spent in a former home with a former lover, clementines suddenly foreboding a lonesome winter ahead. From my unsuspecting train seat, I was catapulted into an existential hole by nothing more than a single scent — that’s how piercing, how immediate and invasive, the power of smell is.
Incidentally, that same clementine-peeling friend had once written that “the world of scents is at least as rich as the world of sight” — a richness best articulated by Diane Ackerman, supreme poet of science, in her 1990 masterwork on the senses.
But even before Ackerman, another enchanting science-storyteller — the physician, etymologist, poet, and essayist Lewis Thomas (November 25, 1913–December 3, 1993) — examined the subject in a beautiful 1985 essay found in A Long Line of Cells: Collected Essays (public library).
Thomas considers the singular poetics of scent as a mode of knowing the world:
I should think we might fairly gauge the future of biological science, centuries ahead, by estimating the time it will take to reach a complete, comprehensive understanding of odor. It may not seem a profound enough problem to dominate all the life sciences, but it contains, piece by piece, all the mysteries. Smoke: tobacco burning, coal smoke, wood-fire smoke, leaf smoke. Most of all, leaf smoke. This is the only odor I can will back to consciousness just by thinking about it. I can sit in a chair, thinking, and call up clearly to mind the smell of burning autumn leaves, coded and stored away somewhere in a temporal lobe, firing off explosive signals into every part of my right hemisphere. But nothing else: if I try to recall the thick smell of Edinburgh in winter, or the accidental burning of a plastic comb, or a rose, or a glass of wine, I cannot do this; I can get a clear picture of any face I feel like remembering, and I can hear whatever Beethoven quartet I want to recall, but except for the leaf bonfire I cannot really remember a smell in its absence. To be sure, I know the odor of cinnamon or juniper and can name such things with accuracy when they turn up in front of my nose, but I cannot imagine them into existence.
In a passage that calls to mind Richard Feynman’s famous Ode to a Flower and the idea that scientific understanding only amplifies rather than diminishing the magic of our sensory perception, Thomas writes:
The act of smelling something, anything, is remarkably like the act of thinking itself. Immediately, at the very moment of perception, you can feel the mind going to work, sending the odor around from place to place, setting off complex repertoires throughout the brain, polling one center after another for signs of recognition, old memories, connections. This is as it should be, I suppose, since the cells that do the smelling are themselves proper brain cells, the only neurons whose axones carry information picked up at first hand in the outside world… The olfactory receptors of mice can smell the difference between self and nonself, a discriminating gift coded by the same H-2 gene locus governing homograft rejection. One wonders whether lymphocytes in the mucosa may be carrying along this kind of genetic information to donate to new generations of olfactory receptor cells as they emerge from basal cells.
Indeed, the sensory powers of other species remind us of our own limitations — after all, as one of the greatest scientists of our time has written, “most people mistake their own perspective, shaped by their subjective and limited perception, for the absolute reality of the external world.” With an eye to the dog’s olfactory supremacy, Thomas writes:
If you are looking about for things to even out the disparity between the brains of ordinary animals and the great minds of ourselves, the superprimate humans, this apparatus is a good one to reflect on in humility. Compared to the common dog, of any rodent in the field, we are primitive, insensitive creatures, biological failures. Heaven knows how much of the world we are missing.
Thomas ends on a wonderfully poetic note, calling for a kind of olfactory conservation movement:
We should be hanging on to some of the few great smells left to us, and I would vote for the preservation of leaf bonfires, by law if necessary. This one is pure pleasure, fetched like music intact out of numberless modular columns of neurons filled chockablock with all the natural details of childhood, firing off memories in every corner of the brain. An autumn curbside bonfire has everything needed for education: danger, surprise (you know in advance that if you poke the right part of the base of leaves with the right kind of stick, a blinding flare of heat and fragrance will follow instantly, but it is still an astonishment when it happens), risk, and victory over odds (if you jump across at precisely the right moment the flare and sparks will miss your pants), and above all the aroma of comradeship (if you smell that odor in the distance you know that there are friends somewhere in the next block, jumping and exulting in their leaves, maybe catching fire)…
It was a loss to give up the burning of autumn leaves. Now … we rake them up and cram them into great black plastic bags, set out at the curb like wrapped corpses, carted away by the garbage truck to be buried somewhere or dumped in the sea or made into fuel or alcohol or whatever it is they do with autumn leaves these days. We should be giving them back to the children to burn.
In the remainder of A Long Line of Cells, biology and beauty dwell as compatriots in the kingdom of knowledge — the kind of bewitching science-storytelling reminiscent of Oliver Sacks and Stephen Jay Gould. Complement this particular essay with the smell of violence and how our limited perception is making us miss most of reality.
Published October 28, 2015