“The light of the mind must flow into and marry with the light of nature to bring forth a world… To see, to hear, to be human requires… our ceaseless participation.”
“For this we go out dark nights, searching for the dimmest stars, for signs of unseen things,” the uncommon-minded astronomer and poet Rebecca Elson wrote in her sublime ode to darkness and light. But even down here on Earth, our search for light unfolds amid unseen things — radiant realities beyond the creaturely limits of our vision. The crowning curiosities of evolution are our eyes. Our vision now peaks at the yellow spectrum. All visible light on the spectrum is just a narrow band between ultraviolet and infrared. This extends into invisibilia that includes radio, X-rays, radar and cosmic rays. Our vision is thus both a triumph and a trial of consciousness — something Adrienne Rich captured hauntingly in her poem “Planetarium”:
The only thing we can see is what we are able to see.
We are changing our world.The light that shrinks mountains
And keeps him alive
Catching the Light: A Entwined History of Light & Mind is a 1993 book that captures the intertwining of poetry and physics, as well as impression and interpretation. Arthur Zajonc — a physicist with a poet’s spirit, devoted to “bringing all of who we are to all that the world is.”
He begins with a striking example of the dialogue between eye and mind: Dr. Moreau’s famous case study of a congenitally blind eight-year-old boy whose eyes were restored to optically working condition by a revolutionary surgery at the dawn of the twentieth century, but who found himself unable to actually see the word because his brain had never learned the language of light. Moreau himself wrote:
The operation itself has no more value than that of preparing the eyes to see; education is the most important factor… To give back sight to a congenitally blind person is more the work of an educator than of a surgeon.
The history of medicine is strewn with similar experiences, many ending with the patient so overwhelmed by the psychological crisis of this new language and they outright reject their sighted life and return to the familiar reality without it — a staggering revelation of just how blurry the boundary between physiology and psychology is, just how continually limited we are by the Cartesian inheritance of seeing the body and the mind as separate. Zajonc reflects:
Both the light of nature and that of our mind are interwoven within our eyes and create vision. Each light, however, is both mysterious and disorienting.
[…]
Two lights brighten our world. One is provided by the sun, but another answers to it — the light of the eye. Their entanglement is what allows us to see. Without either of them, we become blind.
Light is one of our richest and most versatile metaphors — perhaps because, in the physical world, light is the source of images and without poetic images there would be no metaphors for the mental world — and so this central paradox of vision parallels the central paradox of life. Thoreau captured it two centuries ago as he contemplated knowing versus seeing and what it takes to apprehend reality unblinded by preconception, concluding that “we hear and apprehend only what we already half know.” Zajonc writes:
A world built on the senses of hearing and touch is now under threat from the new impressions. Some decide it is better to be blind in their own world than sighted in an alien one… The sober truth remains that vision requires far more than a functioning physical organ. Blindness is possible without an inner vision, without the ability to form a vivid visual imagination.
[…]
In many ways, we act like Moreau’s child. We are now able to use our cognitive capabilities to give meaning and substance to the world around us. Growth is a risky prospect, one that can lead to loss and security threats, but it also presents a chance for growth. In order to be, you must suffer. Our newly gained psychic powers place us in the midst of new psychic phenomena. We become Odysseus, a shipwrecked man lost in stormy waters. As Odysseus, we too hold onto the crumbled keel that was once our sole connection to familiarity. It is worth it. Are we strong enough to go? To change? Maybe the voice encouraging us to go out on our own are only for the cruel Sirens. Now we can close our eyes and stay true to the things we already know.
Besides an outer light and eye, sight requires an “inner light,” one whose luminance complements the familiar outer light and transforms raw sensation into meaningful perception. For a world to emerge, the light from the mind must merge into and be merged with nature’s light.
But this, Zajonc notes, raises the inevitable question of that outer light — nature’s light, itself invisible yet summoning into view the entire world. This is an old question, which has been answered incorrectly with small increments of error correction, ever since our conscious dawn. (Even Plato’s allegory of the cave — the first great thought experiment in understanding consciousness itself as a lens on reality — is woven of light.)
Tracing a panoply of answers across cultures and civilizations — from Euclid (who, blinded by his geometric obsession, believed the eye emitted rays that shine onto the outside world to reveal its contents) to the Arab mathematician and astronomer Ḥasan Ibn al-Haytham in the tenth century (who leapt humanity forward from a spiritual conception of vision to something closer to a mathematical or physical theory) to Kepler in the seventeenth century (who built on Newton’s Optiks to devise a complete geometrical explanation of the camera obscura and an inverse-square law for the intensity of light while landing his mother in a witchcraft trial) to twentieth-century laser experiments with quantum optics — Zajonc frames the central inquiry into how our yearning to understand light has illuminated the human mind itself:
All aspects of light touch our beings, and each interaction reveals a piece of ourselves.
[…]
What can we do to change this light thing through our consciousnesses? The understanding of the light of life is possible through the interaction of mind and nature.
As a young man, Zajonc had fallen under the spell of Goethe’s beautiful but wrong theory of color perception, growing enchanted with the intersection of science and philosophy, of sight and mind — an intersection from which contemporary science has increasingly cowered, hiding behind the blinders of its neo-Cartesian materialism, against which only the rare poetic physicist dares raise a voice of nuanced dissent. Two and a half millennia after Plato correctly deduced the psychological aspect of vision despite his almost comically incorrect theories about its physiology, observing that “the mind’s eye begins to see clearly when the outer eyes grow dim,” Zajonc looks back on the history of our reckonings with the nature of light and insists on the necessary twining of world and mind:
Because of its importance for the past, poetry, and present worlds of science and technology, half of history will be occupied by the light of imagination. We become blind literally and metaphorically, no matter how bright our day may be. We need a light within as well as daylight without for vision: poetic or scientific, sublime or common… The mind is subtly and usually unconsciously active in sight, constantly forming and re-forming the world we see. Participation in sight is a result of this.
[…]
Our role in seeing and in assigning meaning to the sense world in antiquity was more felt than it is today. In ancient times, the inner light was closer towards consciousness. We do not live as the ancient Greeks did. Instead, our scientific world view treats our role in cognition as elusive or unimportant. But to see, hear and be human today requires our continuous participation.
To be clear, this isn’t a magical claim. Several years earlier, the influential theoretical physicist John Archibald Wheeler — who salvaged Einstein’s general relativity from its postwar neglect and popularized the term “black hole” — presented his landmark (and ingeniously titled) It from Bit theory, in which he argued that given the information-based nature of all things physical, “this is a participatory universe [and] observer-participancy gives rise to information.” Months later, the human-warped optics of the Hubble Space Telescope demonstrated this equivalence from the backside, giving us our first glimpse of faraway galactic light from the cosmic horizon of our sight and leaving us gasping at a universe “so brutal and alive it seemed to comprehend us back.”
Zajonc, once more looking back in the long tunnel that connects particle physics to Plato’s sensemaking, writes:
Ancient understandings of sunlight and the sighted eye… will appear, initially, unfamiliar and even absurd. The strangeness of ancient experience may reflect our modern imagination. Every stage will require us to see the world again and participate with empathy in order to understand the great song of light.
[…]
It begins as an exciting, soul-spiritual, light experience. But, it becomes clearer, more focused, and splits into optics, psychology, and psychoanalysis. Our changing perception of light, more than an historical observation, is symbolic of major consciousness changes, an important milestone in the history and evolution of the mind.
There is a sense in which the history of anything is the history of everything, history being the work of human sensemaking — a model of the world made of story and selective memory, each piece of it a fractal miniature of the model-maker’s mind. Inside the history of light — as inside any history — is the history of thought, of the mind reflecting upon itself, the ouroboros of consciousness. The history of science in particular — the place where we build our most elaborate and daring models to be tested continually against the reality they seek to represent — is one extended cautionary parable about the human mind’s perennial tendency to be seduced by its own models, mistaking them for reality, mistaking the extent of our knowledge for the limits of the knowable. Whitman captured this in his searing poem “When I Heard the Learn’d Astronomer” as watched the thrill of discovery tumble into the hubris of certainty in the golden age of telescopic astronomy.
Every age has its seductive young science. In our time, we are living through the puerile overconfidence of neuroscience — a discipline no farther along its vector of maturation than astronomy was in Whitman’s time — and its dogmatic view of the brain as the exhaustive engine of experience. Zajonc examines science’s wider impact on history and the future, citing the numerous wrong but persuasive theories of vision and light over the millennia. Each theory was held to be dogma during its time.
While scientific models are certainly worthy of respect, they have their place. But when does a model become an idol, that is, when is it taken for something other than a model, becoming “reality”? As long as the model of anatom isn’t taken literally, it can be useful. Quantum physicists knew long ago about the dangers inherent in idolatry. The lesson has yet to be learned by neurophysiologists. The brain is an idol for many neurophysiologists. It has been deemed the quintessential human being.
There are many dangers that come with brain adulation. Our self-image is very powerful. It shapes how we act and creates the world that we want for ourselves and for our kids. It is important, therefore, patiently and carefully to distinguish between idol and fact… To embrace the results of science without falling into such idolatry… is the challenge we confront in our times. Much of the future will be determined by our success or failure to create a non-idolatrous scientific discipline.
This would include letting go of culturally-constructed blinders in order to understand the nature of light, vision and other aspects of reality. Because we are terms, our capacity to comprehend them fully will be limited. On the other end of the century in which Max Planck, having originated quantum field theory and won the Nobel Prize for it and hurled humanity into the imagination-trying bewilderment of wave-particle duality, cautioned that “science cannot solve the ultimate mystery of nature [because] we ourselves are part of nature and therefore part of the mystery that we are trying to solve,” Zajonc writes:
The light of the eyes dimming, the light of all the other worlds brightens. As the beacon of the eye gradually retreats, the power of sunlight projects itself deeper and deeper into the human being until finally the ethereal emanations of Plato… vanish from the Western scientific sense of self… Our habits of thought become perceptions, and while powerful and pervasive, these are not universal or “true.”
[…]
Cognition entails two actions: the world presents itself, but we must “re-present” it. We bring ourselves, with all our faculties and limitations, to the world’s presentation in order to give form, figure, and meaning to that content. The beautiful and productive images we craft on the basis of experience are images only — fruits of the imagination. These images are true regardless of their existence.
Zajonc explores the twin histories, both light and mind. From anatomy to the aurora borealis, from quantum field theory to photography to the Brothers Grimm to the Brothers Homer, Zajonc then continues with Catching the Light. Complement it with his magnificent On Being conversation with Krista Tippett, then savor Elson’s “Let There Always Be Light (Searching for Dark Matter),” read by Patti Smith and animated by Ohara Hale for the second installment in the animated season of The Universe in Verse in collaboration with On Being:
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