“Smells detonate softly in our memory like moving land mines, hidden under the weedy mass of many years and experiences. Hit a tripwire of smell, and memories explode all at once. A complex vision leaps out of the undergrowth.”

Ackerman employs a metaphor, comparing smells to “moving land mines” to illustrate their sudden and explosive ability to evoke memory. This highlights the involuntary and deeply emotional nature of scent-based recall, where a single smell can instantly trigger a cascade of complex, long-buried experiences and feelings from the past. The oxymoron “detonate softly” is emblematic of Ackerman’s style, which relies on surprising images and metaphors to jar readers into thinking in new ways.

“Smell is the mute sense, the one without words. Lacking a vocabulary, we are left tongue-tied, groping for words in a sea of inarticulate pleasure and exaltation.”

Ackerman asserts that smell is even more inaccessible to language than the other senses are. She argues that this lack of a dedicated vocabulary is why describing an odor is so difficult, highlighting The Inadequacy of Language to Describe Sensation. This “muteness” is a source of smell’s mysterious power.

“Unlike the other senses, smell needs no interpreter. The effect is immediate and undiluted by language, thought, or translation. A smell can be overwhelmingly nostalgic because it triggers powerful images and emotions before we have time to edit them.”

Ackerman explains the neurological basis for smell’s unique emotional potency. She argues that because olfactory signals travel directly to the brain’s ancient limbic system, they bypass rational thought and trigger raw, unedited memories and feelings. This direct pathway makes smell a uniquely powerful, involuntary key to our emotional past.

“Smell was the first of our senses, and it was so successful that in time the small lump of olfactory tissue atop the nerve cord grew into a brain. Our cerebral hemispheres were originally buds from the olfactory stalks. We think because we smelled.”

Ackerman makes a bold evolutionary claim about the primacy of smell in the development of human consciousness. She argues that the complex cognitive functions we associate with the brain are a direct outgrowth of the need to process smells for survival. The last line here borrows the structure of Rene Descartes’s famous dictum, “I think, therefore I am,” suggesting a fundamental reframing of the relationship between body and mind.

“Our skin is what stands between us and the world. If you think about it, no other part of us makes contact with something not us but the skin. It imprisons us, but it also gives us individual shape, protects us from invaders, cools us down or heats us up as need be, produces vitamin D, holds in our body fluids.”

Ackerman establishes the skin as a paradoxical organ that both defines our isolation and facilitates our connection to the world. She portrays this boundary as a dynamic, life-sustaining system. This framing presents touch, the skin’s sense, as fundamental to our distinct identity and our physical survival.

“Language is steeped in metaphors of touch. We call our emotions feelings, and we care most deeply when something ‘touches’ us. Problems can be thorny, ticklish, sticky, or need to be handled with kid gloves. Touchy people, especially if they’re coarse, really get on our nerves.”

Ackerman demonstrates that touch is a primary sense structuring our abstract thought by showing how our vocabulary for emotion and reality is built on tactile metaphors. She suggests that our gravest concepts are grounded in physical experience. For Ackerman, language itself reveals the foundational importance of the sense of touch.

“In the absence of touching and being touched, people of all ages can sicken and grow touch-starved.”

Ackerman makes the incisive claim that touch is not a luxury but a biological necessity, akin to food. By coining the term “touch-starved,” she reframes sensory deprivation as a form of malnourishment that has severe physical and psychological consequences. This asserts the sense’s essential role in human health and development.

“Touch receptors can be blanked out simply by tedium. When we put on a heavy sweater, we’re acutely aware of its texture, weight, and feel against our skin, but after a while we completely ignore it. A constant consistent pressure registers at first, activating the touch receptors; then the receptors stop working.”

Ackerman explores how our sensory system actively constructs our reality by filtering information. She argues that touch, like our other senses, is attuned to change rather than stasis. This process of adaptation demonstrates that our perception of the world is not a complete record but a selective and efficient mental model.

“But, above all, touch teaches us that life has depth and contour; it makes our sense of the world and ourself three-dimensional. Without that complex feel for life there would be no artists, whose cunning is to make sensory and emotional maps, and no surgeons, who dive through the body with their fingers.”

Ackerman concludes her reflection on touch by connecting it directly to our conceptual understanding of reality. She argues that touch provides the essential data for a three-dimensional world, not only shaping our personal sense of self but also enabling complex social endeavors like art and medicine.

“Throughout the world, the stratagems of business take place over meals; weddings end with a feast; friends reunite at celebratory dinners; children herald their birthdays with ice cream and cake; religious ceremonies offer food in fear, homage, and sacrifice; wayfarers are welcomed with a meal.”

Ackerman illustrates the deeply social nature of taste by cataloging life’s key moments—from business deals to weddings—that are consecrated with meals. This reinforces her argument that eating is a fundamental human ritual used to mark significance, forge connections, and build community, making taste a uniquely communal sense.

“But omnivores are anxious eaters. They must continually test new foods to see if they’re palatable and nutritious, running the risk of inadvertently poisoning themselves. They must take chances on new flavors, and, doing so, they frequently acquire a taste for something offbeat that, though nutritious, isn’t the sort of thing that might normally appeal to them—chili peppers (which Columbus introduced to Europe), tobacco, alcohol, coffee, artichokes, or mustard, for instance.”

Ackerman defines the “anxious eater” to highlight the psychological cost of being an omnivore. Unlike animals with restricted diets, humans must constantly experiment with new foods, risking poison for the reward of nutrition. This inherent tension between curiosity and danger has driven us to acquire tastes for unusual and potentially risky substances.

“A food’s flavor includes its texture, smell, temperature, color, and painfulness (as in spices), among many other features. Creatures of sound, we like some foods to titillate our hearing more than others. There’s a gratifying crunch to a fresh carrot stick, a seductive sizzle to a broiling steak, a rumbling frenzy to soup coming to a boil, an arousing bunching and snapping to a bowl of breakfast cereal.”

Ackerman expands the definition of flavor beyond mere taste, arguing it is a symphonic experience involving all senses. The sound of a “gratifying crunch” or a “seductive sizzle” is as important to our enjoyment as smell or mouthfeel. This demonstrates how our perception of food is a holistic, multisensory event.

“In our hearts, we know that life loves life. Yet we feast on some of the other life-forms with which we share our planet; we kill to live. Taste is what carries us across that rocky moral terrain, what makes the horror palatable, and the paradox we could not defend by reason melts into a jungle of sweet temptations.”

Ackerman confronts the ethical dilemma at the heart of being an omnivore: the necessity of killing to live. She proposes that taste is the psychological mechanism that makes this “horror palatable.” The pleasure of taste allows us to resolve a fundamental moral paradox, transforming a violent act into a sensory delight.

“The assumption hidden in this etymological nest of spiders is that the world will still make sense to someone who is blind or armless or minus a nose. But if you lose your sense of hearing, an important thread dissolves and you lose track of life’s logic.”

Ackerman posits that hearing is uniquely essential for our cognitive grasp of the world. By tracing the etymology of “absurdity” back to deafness, she argues that hearing provides a fundamental structure for “life’s logic”—by which she means a social world organized around verbal communication. This etymology reflects a historical injustice: Prior to the advent of widespread literacy and the development of complex sign languages, deaf people were often cut off from communication, and as a result it was often wrongly assumed that deafness implied cognitive impairment.

“In the course of evolution, speech must have been so important to survival that it was worth the risk of choking.”

Ackerman uses a significant biological trade-off to argue for the deep survival value of sound-based communication. The human larynx’s position enables speech but creates a potentially fatal choking risk. This anatomical compromise demonstrates that for early humans, the ability to communicate complex ideas through sound was more evolutionarily advantageous than having a perfectly safe airway.

“Deafness is a much worse misfortune. For it means the loss of the most essential stimulus—the sound of the voice that brings language, sets thoughts astir and keeps us in the intellectual company of man.”

Ackerman quotes Helen Keller to argue that hearing is more essential to human connection than sight. Keller, who was both blind and deaf, valued hearing more because it is the medium of language, thought, and community. Its loss severs one from the “intellectual company of man,” a deep isolation.

“We listen with our bodies. Indeed, it’s hard to keep our bodies still when we hear music—our feet begin tapping, our hands begin swaying, we pick up an invisible baton, or gyrate in some sketchy dance movements.”

Ackerman asserts that our connection to music is deeply physical, not merely intellectual or auditory. The involuntary bodily responses we have to rhythm—tapping feet, swaying hands—demonstrate that music engages the entire nervous system. This argument reframes listening as an active, embodied process through which we perceive sound with our entire being.

“Though most of us don’t hunt, our eyes are still the great monopolists of our senses. To taste or touch your enemy or your food, you have to be unnervingly close to it. To smell or hear it, you can risk being farther off. But vision can rush through the fields and up the mountains, travel across time, country, and parsecs of outer space,”

This passage establishes the central thesis for the section on vision: its supremacy among human senses. Ackerman frames sight not just as a biological function but as a source of power. Since light travels much farther than sound or smell, vision allows humans to gather knowledge across great distances.

“Look in the mirror. The face that pins you with its double gaze reveals a chastening secret: You are looking into a predator’s eyes. Most predators have eyes set right on the front of their heads, so they can use binocular vision to sight and track their prey.”

Ackerman opens her exploration of vision by framing human eyes as evolutionary tools inherited from predators. This biological assumption—that our forward-facing eyes are designed for hunting—is a metaphor for a predatory instinct within human nature, though it should be noted that humans are primates, and many non-predatory primates rely on binocular vision to judge distances as they navigate the tree canopy. By linking our physical perception directly to our evolutionary origins as hunters, she challenges a “civilized” self-image.

“However, seeing, as we think of it, doesn’t happen in the eyes but in the brain. In one way, to see flamboyantly, in detail, we don’t need the eyes at all. We often remember scenes from days or even years earlier, viewing them in our mind’s eye, and can even picture completely imaginary events, if we wish.”

Ackerman distinguishes between the biological process of sight and the cognitive experience of seeing. This argument is important to her overarching thesis that our senses build our reality, rather than simply recording it. By locating the act of seeing in the brain, she highlights its subjectivity and its deep connection to memory and imagination.

“Color doesn’t occur in the world, but in the mind. Remember the old paradoxical question: If a tree falls in the forest, and no one is around to hear it, does it make a sound? A parallel question in vision: If no human eye is around to view it, is an apple really red? The answer is no, not red in the way we mean red.”

This passage makes a bold claim about the nature of reality, central to Ackerman’s project of de-familiarizing the senses. By arguing that color exists only in the mind, she repositions human consciousness as an active creator of the world, not just a passive observer.

“What this geometry of beauty boils down to is a portrait of an ideal mother—a young, healthy woman. A mother had to be fertile, healthy, and energetic to protect her young and continue to bear lots of children, many of whom might die in infancy. Men drawn to such women had a stronger chance of their genes surviving.”

Ackerman grounds perceptions of beauty in evolutionary biology. Her argument posits that our aesthetic judgments are not arbitrary but are deeply encoded survival mechanisms with origins in prehistory. This framing places her on one side of a long-standing debate, with the other side comprised of those who argue that beauty is socially and culturally constructed and that the present-day cultural landscape is more salient than the evolutionary imperatives of the distant past.

“Great artists feel at home in the luminous spill of sensation, to which they add their own complex sensory Niagara.”

This quote is a concise thesis for the author’s argument about the relationship between art and perception. By characterizing artists as being “at home” in a “luminous spill of sensation,” she uses her own poetic imagery to highlight the artist’s role as a contributor to the complex human world of perception and cognition.