Paul Kalanithi, a neurosurgeon, wanted badly to understand life and its meaning, and he knew that to do so he would need to understand death. So when in his 30s he developed a cancer that he knew would kill him, he thought (and subsequently wrote): “Shouldn’t terminal illness, then, be the perfect gift to that young man who had wanted to understand death? What better way to understand it than to live it? But I’d had no idea how hard it would be, how much terrain I would have to explore, map, settle.”

In his highly acclaimed book When Breath Becomes Air published after his death he describes the terrain he explored, mapped, and settled. The book is an autobiography with the second half describing his experience of his illness; and his wife, Lucy Kalanithi, an internist, added a chapter on his death and the aftermath. His terminal illness may have been a perfect gift and it certainly adds impact and narrative to his book, but I was fascinated more by the first half.

Kalanithi loved books, and the natural place for him to find meaning seemed to be in literature and philosophy. His father was a doctor, and he decided positively against studying medicine. His plan was to read English literature at Stanford, but a bizarre book led him also to study biology. He read in a day  Satan:His Psychotherapy and Cure by the Unfortunate Dr. Kassler, JSPS by Jeremy Leven and was hit with force by the idea that “the mind was simply the operation of the brain.” He studied the mind and the brain, but a visit to a home for people with severe brain injuries led to the next important step on his journey. “Brains,” he realised, “give rise to our ability to form relationships and make life meaningful” but “Sometimes, they break.”

After writing a thesis on “Whitman and the Medicalization of Personality” Kalanithi understood that he didn’t quite fit into a department of English. Where, he asked himself, do “biology, morality, literature, and philosophy intersect?” A voice, which he compares, to “Augustine’s voice in the garden” commanded him “Set aside the books and practice medicine.” He became a medical student.

I doubt that many people take up medicine in order to understand the meaning of life and death, but for Kalanithi this was an intellectual search: “I found myself increasingly often arguing that direct experience of life-and-death questions was essential to generating substantial moral opinions about them….It was only in practicing medicine that I could pursue a serious biological philosophy. Moral speculation was puny compared to moral action.”

It was perhaps inevitable that he would become a “brain doctor” of some sort. Psychiatry might have led him back into the thickets of philosophy and literature, and neurology was perhaps too passive for a man who wanted to understand through action. He opted for neurosurgery.

“I was compelled by neurosurgery, with its unforgiving call to perfection; like the ancient Greek concept arete, I thought, virtue required moral, emotional, mental, and physical excellence. Neurosurgery seemed to present the most challenging and direct confrontation with meaning, identity, and death.”

He entered a bravado, macho, unforgiving, even arrogant world. “My first day in the hospital, the chief resident said to me, “Neurosurgery residents aren’t just the best surgeons— we’re the best doctors in the hospital. That’s your goal. Make us proud.” This was no place for the faint-hearted or perhaps for those who thought and reflected too much. Kalanithi seemed to work 18 hours a day seven days a week, but it was never enough.

Surrounded by suffering, pain, and death and having to make life and death decisions with the overtone that some consequences might be worth than death, he got his chance to learn about meaning in this philosophical crucible: “I had started in this career, in part, to pursue death: to grasp it, uncloak it, and see it eye-to-eye, unblinking. Neurosurgery attracted me as much for its intertwining of brain and consciousness as for its intertwining of life and death.”

But it was tough: “At moments, the weight of it all became palpable. It was in the air, the stress and misery. Normally, you breathed it in, without noticing it. But some days, like a humid muggy day, it had a suffocating weight of its own. Some days, this is how it felt when I was in the hospital: trapped in an endless jungle summer, wet with sweat, the rain of tears of the families of the dying pouring down.”

He then began to doubt that neurosurgery was the best place to understand life’s meaning. “In the midst of this endless barrage of head injuries, I began to suspect that being so close to the fiery light of such moments only blinded me to their nature, like trying to learn astronomy by staring directly at the sun.” He began to worry that he was losing his humanity: “I observed a lot of suffering; worse, I became inured to it.”

Literature helped him. “I feared I was on the way to becoming Tolstoy’s stereotype of a doctor, preoccupied with empty formalism, focused on the rote treatment of disease— and utterly missing the larger human significance.“  He quotes Tolstoy: “Doctors came to see her singly and in consultation, talked much in French, German, and Latin, blamed one another, and prescribed a great variety of medicines for all the diseases known to them, but the simple idea never occurred to any of them that they could not know the disease Natasha was suffering from.”

He still loved the work, and, seeming almost to contradict himself, he writes: “I don’t think I ever spent a minute of any day wondering why I did this work, or whether it was worth it. The call to protect life— and not merely life but another’s identity; it is perhaps not too much to say another’s soul— was obvious in its sacredness.”

Perhaps unlike some doctors, he recognises that death is not the enemy. “As a resident, my highest ideal was not saving lives— everyone dies eventually— but guiding a patient or family to an understanding of death or illness….In these moments, I acted not, as I most often did, as death’s enemy, but as its ambassador.” This impressed me, as did his thought that “When there’s no place for the scalpel, words are the surgeon’s only tool.” Many surgeons, I reflect, are much more comfortable with the scalpel than with words.”

As Kalanithi approached the end of his residency, he felt positive about the choice he had made: “It felt to me as if the individual strands of biology, morality, life, and death were finally beginning to weave themselves into, if not a perfect moral system, a coherent worldview and a sense of my place in it. Doctors in highly charged fields met patients at inflected moments, the most authentic moments, where life and identity were under threat; their duty included learning what made that particular patient’s life worth living, and planning to save those things if possible— or to allow the peace of death if not. Such power required deep responsibility, sharing in guilt and recrimination.”

But then a colleague killed himself after making a mistake with a patient and Kalanithi’s cancer was diagnosed. As he confronted his death he returned to literature: “The privilege of direct experience had led me away from literary and academic work, yet now I felt that to understand my own direct experiences, I would have to translate them back into language….And so it was literature that brought me back to life during this time.”

I found the second half of the book less compelling, and I was unsure about the oncologist, supposedly the very best, who, unlike Kalanithi, did seem to see her job as defeating death. When he’s close to death she insists he has another five years. He had what felt to me a medicalised death, one that would be unaffordable to most people in the world. He and his wife after much debate decided to have a child, and advanced technology was needed to achieve the pregnancy. Some might think that decision unwise, but Kalanithi ends his book describing the great joy his daughter gave him and hoping that when she weighs up her life she will think of the joy she gave her dying father as one of her achievements.

Kalanithi has, as he hoped he would, written a great book and reflected as deeply as anybody on what it is to be a doctor: “The physician’s duty is not to stave off death or return patients to their old lives, but to take into our arms a patient and family whose lives have disintegrated and work until they can stand back up and face, and make sense of, their own existence.”

Richard Smith was the editor of The BMJ until 2004. 

Competing interest: RS is an unpaid adjunct professor in the Institute of Global Health Innovation.