“That is happiness,” Willa Cather wrote, “to be dissolved into something complete and great.” We have many names for that dissolution, all revolving around some sense of spirituality and they all involving what Iris Murdoch so splendidly termed “unselfing” — experiences, most often furnished by art, music, and nature, that allow us to “pierce the veil of selfish consciousness and join the world as it really is.”

At the heart of both our spirituality and our science lies this eternal yearning to know the world as it really is — a yearning with an infinite vector, pointing always just past the horizon of our knowledge, anchored always in the most elemental nature of the human animal: our curiosity, our restlessness, our hunger for truth and transcendence.

And yet the reflex of selfing, which stands so often between us and elemental truth, between us and transcendence, is hard-wired in our physiology — our entire experience of reality is lensed through our individual consciousness, housed in the brain and tendrilled through the body. Coursing through our nervous system as electrical signals beckoning to neurons are the tremors of falling in love and the anguish of grief, all of our feelings meted out by charged particles moving at eighty feet per second. The stuff of poetry and the stuff of dreams, all a particulate cloud of coruscating matter.

In The Transcendent Brain: Spirituality in the Age of Science (public library), the poetic physicist Alan Lightman sets out to illuminate how these atomic constellations can be capable of such exultant spiritual experiences, aglow with such shimmering feelings. From the prescient atomic materialism of Lucretius to Maxwell’s equations, from the poems of Emily Dickinson to the synchronized firing of neurons in recognizing a loved one’s face, from the Hindu concept of darshan — the beholding of a deity or sacred object — to the cosmic wonders we have beheld through the “oracle eye” of our majestic space telescopes, he argues that spiritual experiences “are as natural as hunger or love or desire, given a brain of sufficient complexity.” Radiating from the millennia-wide inquiry is a revelation about how mere atoms and molecules can give rise to the very persuasive experience of a self, of a soul, of something that feels so vast and complex and magnificently irreducible to matter.

He writes:

I’m a scientist and have always had a scientific view of the world — by which I mean that the universe is made of material stuff, and only material stuff, and that stuff is governed by a small number of fundamental laws. Every phenomenon has a cause, which originates in the physical universe. I’m a materialist. Not in the sense of seeking happiness in cars and nice clothes, but in the literal sense of the word: the belief that everything is made out of atoms and molecules, and nothing more. Yet, I have transcendent experiences. I communed with two ospreys that summer in Maine. I have feelings of being part of things larger than myself. I have a sense of connection to other people and to the world of living things, even to the stars. I have a sense of beauty. I have experiences of awe. And I’ve had transporting creative moments.

The aggregate of these very different types of experiences, echoes of which reverberate through every human life, is what he terms “spirituality” — a notion he nests inside the paradox of materiality and irreducibility:

I believe that the spiritual experiences we have can arise from atoms and molecules. At the same time, some of these experiences, and certainly their very personal and subjective nature, cannot be fully understood in terms of atoms and molecules. I believe in the laws of chemistry and biology and physics — in fact, as a scientist I much admire those laws — but I don’t think they capture, or can capture, the first-person experience of making eye contact with wild animals and similar transcendent moments. Some human experiences are simply not reducible to zeros and ones.

Therein lies the paradox — given that “all mental sensations are rooted in the material neurons of the nervous system and the electrical and chemical interactions between them,” how can this inescapable materiality wing us with such feelings of spirituality?

He gives a radiant answer in an orientation he calls “spiritual materialism” — the idea that even with a lucid understanding of how nature works, and how we work as material miniatures of nature’s laws, we are capable of transcendent experiences arising from the dazzling tessellation of atoms we call consciousness. Those experiences contour our highest humanity: our investment in living a moral life and stewarding the happiness of others, our capacity for awe and wonder, our sensitivity to beauty.

Recounting his own earliest memory of a spiritual experience as a child enchanted with the scientific method, he writes:

Although as a child I developed a scientific view of the world, I also understood that not all things were subject to quantitative analysis… I was about nine years old. It was a Sunday afternoon. I was alone in a bedroom of my home in Memphis, Tennessee, gazing out the window at the empty street, listening to the faint sound of a train passing a great distance away. Suddenly I felt that I was looking at myself from outside my body. For a brief few moments, I had the sensation of seeing my entire life, and indeed the life of the entire planet, as a brief flicker in a great chasm of time, with an infinite span of time before my existence and an infinite span of time afterward. My fleeting sensation included infinite space. Without body or mind, I was somehow floating in the gargantuan stretch of space, far beyond the solar system and even the galaxy, space that stretched on and on and on. I felt myself to be a tiny speck, insignificant. A speck in a huge universe that cared nothing about me or any living beings and their little dots of existence — a universe that simply was. And I felt that everything I had experienced in my young life, the joy and the sadness, and everything that I would later experience meant absolutely nothing in the grand scheme of things. It was a realization both liberating and terrifying at once… Despite the dismal feeling that the universe didn’t care a whit about me, I did feel connected to something far larger than myself.

Again and again, he returns to this feeling of connection to something beyond the self as the crucible of our transcendent experiences and the beating heart of everything we call spirituality:

A common feature of all aspects of spirituality is a loss of self, a letting go, a willingness to embrace something outside of ourselves, a willingness to listen rather than talk, a recognition that we are small and the cosmos is large.

And yet this too is a psychological paradox rooted in our physiology:

Most transcendent experiences are completely ego-free. In the moment, we lose track of time and space, we lose track of our bodies, we lose track of our selves. We dissolve. And yet… spirituality emerges from consciousness and the material brain. And the paramount signature of consciousness is a sense of self, an “I-ness” distinct from the rest of the cosmos. Thus, curiously, a thing centered on self creates a thing absent of self.

[…]

More self, less connection to the larger world.

Since the dawn of our species, myths and religions have tried to resolve this paradox with the concept of the soul — a vessel of I-ness that exists beyond the material realm, often conceived of as a kind of supra-energy. And yet despite the long cultural and theological history of belief in an immaterial soul, in reality all energy is accounted for by the forces of nature and their descriptive equations. He considers how our mortality — the entropic fate of all matter, the antipode of the myth of the immortal soul — is the true crucible of our connection to each other and the immensity beyond us, the wellspring of all of our creativity:

For me, the notion that our atoms were once part of other people and will again become part of other people after we die provides a meaningful connectedness between us and the rest of humanity, future and past.

[…]

Our inescapable death may be the single most powerful fact of our brief existence in this strange cosmos where we find ourselves. Indeed, one could argue that much of our thinking, our view of the world, our artistic expression, and our religious beliefs involve coming to terms with this fundamental fact.

The fact of our death is also what binds us to all life, stretching all the way back to the Big Bang, reminding us of the borrowed stardust that we are:

If you could tag each of the atoms in your body and follow them backward in time, through the air that you breathed during your life, through the food that you ate, back through the geological history of the Earth, through the ancient seas and soil, back to the formation of the Earth out of the solar nebular cloud, and then out into interstellar space, you could trace each of your atoms, those exact atoms, to particular massive stars in the past of our galaxy. At the end of their lifetimes, those stars exploded and spewed out their newly forged atoms into space, later to condense into planets and oceans and plants and your body at this moment.

Drawing on his splendid earlier writings about what actually happens when we die, he projects this atomic tagging forward into a future in which his I-ness is no more:

The atoms in my body will remain, only they will be scattered about. Those atoms will not know where they came from, but they will have been mine. Some of them will once have been part of the memory of my mother dancing the bossa nova. Some will once have been part of the memory of the vinegary smell of my first apartment. Some will once have been part of my hand. If I could label each of my atoms at this moment, imprint each with my Social Security number, someone could follow them for the next thousand years as they floated in air, mixed with the soil, became parts of particular plants and trees, dissolved in the ocean, and then floated again to the air. And some will undoubtedly become parts of other people, particular people. So, we are literally connected to the stars, and we are literally connected to future generations of people. In this way, even in a material universe, we are connected to all things future and past.

Radiating from the remainder of The Transcendent Brain, as it traces the history of science and the history of culture, is a largehearted invitation to “stand on the precipice between the known and the unknown, without fear, without anxiety, but instead with awe and wonder at this strange and beautiful cosmos we find ourselves in.” Complement it with Rachel Carson on science and our spiritual bond with nature, then revisit the great naturalist John Burroughs’s century-old manifesto for spirituality in the age of science.