Most people’s views of the brain-body divide go something like this: Our bodies gather information, through sight, touch, and sounds. That information gets sent to our brain, our “mind,” where we think about it and decide how to act on it. We see a dog walking toward us, think about whether it’s the neighbor’s or if it looks friendly, and tell our bodies whether to pet it or run. This all seems straightforward and maps pretty cleanly onto our conscious experience.
But in Intelligence in the Flesh, the cognitive scientist Guy Claxton tells us that this is utterly wrong. It’s not that our conscious mind is different from and in charge of the body; rather, our brain has to work in tandem with our body to make us intelligent.
Claxton’s argument is drawn from a broad, burgeoning field called embodied cognition, which argues that cognitive processes aren’t separate from senses and motor functions. As Claxton puts it, “the body, the gut, the senses, the immune system, the lymphatic system, are so instantaneously and so complicatedly interacting with the brain that you can’t draw a line across the neck and say ‘above the line it’s smart and below the line it’s menial.’”
Computer-programming research has buttressed this view. As has been noted by experts like Hans Moravec, a celebrated robotics professor, advances in artificial intelligence and related fields have brought with them a strange paradox: Tasks we traditionally have thought of as complex — various sorts of abstract reasoning, for example — are fairly easy to program, while tasks that have long been considered simple — walking in a straight line on uneven terrain — have proven elusively difficult to translate into code. Deep Blue defeated world champion Garry Kasparov at chess in 1997, but robots still haven’t mastered the walking thing. As Moravec wrote in the book Mind Children, “The deliberate process we call reasoning is, I believe, the thinnest veneer of human thought, effective only because it is supported by this much older and much more powerful, though usually unconscious, sensorimotor knowledge.”
Or take a classic experiment involving Botox. It’s thought that one way humans understand each other’s facial expressions is by subconsciously and subtly mimicking those expressions. When one study compared two groups of women, one whose members had received Botox, which paralyzes facial muscles, and another whose members had taken Restylane, a dermal filler that doesn’t affect muscle function, there was a big difference. Those who had received Botox were worse at recognizing facial expressions in photographs of others’ eyes.Botox doesn’t affect your brain, but it still affects your emotional intelligence. Intelligence in the Flesh is full of examples like this — of students holding cold packs in an experiment acting coldly toward friends, for instance, or or of people’s gambling aggressiveness being affected by the upright or slouched posture they’re instructed to take during a game played in a research lab.
But even if the body has a bigger role than we might think, isn’t the brain still, well, the brain? Phineas Gage had an iron rod driven through his skull and was then “no longer Gage.” Surely an iron rod through the leg wouldn’t have the same impact — it would be a horrible injury, but it wouldn’t rob Gage of his essential Gageness. Claxton doesn’t dispute the brain’s importance, but doesn’t back down from his thesis, either. He points to Oliver Sacks’s book, A Leg to Stand On, in which Sacks recounted his recovery from a brutal leg injury sustained while hiking.
In it, Sacks describes the physical injury: ”I couldn’t think how to contract the quadriceps any more. I couldn’t ‘think’ how to pull the patella, and I couldn’t ‘think’ how to flex the hip.” But he also focuses on the psychological toll the injury took on him: “What seemed, at first, to be no more than a local, peripheral breakage and breakdown now showed itself in a different, and quite terrible, light — as a breakdown of memory, of thinking, of will — not just a lesion in my muscle, but a lesion in me.” Sacks was no Gage, but he learned that a limb is more than a limb, it’s a part of our being and understanding of ourselves.
To improve this understanding and grow more in-tune with our bodies, Claxton recommends mindfulness meditation, exercise, and techniques like biofeedback training, which uses sensors to teach people to recognize and control biological signals like sweating and muscle tension. He writes that these can improve “interoceptive awareness,” an awareness of one’s own body, including one’s limbs, heart rate, and even stomach sensations. In a randomized controlled trial of adults over 70, lessons in tai chi, which focuses on bodily awareness, significantly reduced participants’ chance of falling, improved their functional balance, and even lessened their fear of falling. Claxton also advocates replacing screen time with hands-on activities using real materials, or even visiting maker spaces. “Devices don’t offer that kind of bracing engagement of working with material, the everyday experience of the glassblower or bookbinder or carpenter.”
Claxton also recommends changes at the societal level. He sees most of Western culture as tilted toward an abstracted intelligence that ignores or denigrates the powerful sensorimotor knowledge Morovec talked about. Consider the trend of calling white-collar jobs “knowledge work,” as if lumberjacks or plumbers manage to work without a single thought passing through their heads. White-collar jobs can be creative and stimulating, but plenty are as monotonous as Charlie Chaplin’s factory work in Modern Times. Nonetheless, there’s still a great deal of social capital in careers that use abstract reasoning, no matter how tediously. Meanwhile, work using the hands is often viewed with, in Claxton’s words, “a whiff of disdain.”
Intelligence in the Flesh is a vociferous argument against this sort of disdain. In fact, the book’s one overriding message is that it’s impossible to separate mind-stuff from body-stuff, whether it’s in algebra, reading people’s faces, or recognizing that dog as friendly.