Paul Kalanithi

Before operating on a patient's brain... I must first understand his mind: his identity, his values, what makes his life worth living, and what devastation makes it reasonable to let that life end.

I have sat with countless patients and families to discuss grim prognoses: It's one of the most important jobs physicians have. It's easier when the patient is 94, in the last stages of dementia, and has a severe brain bleed. For young people like me - I am 36 - given a diagnosis of cancer, there aren't many words.

Had I been more religious in my youth, I might have become a pastor, for it was the pastoral role I'd sought.

During my sojourn in ironclad atheism, the primary arsenal leveled against Christianity had been its failure on empirical grounds. Surely, enlightened reason offered a more coherent cosmos. Surely, Occam's razor cut the faithful free from blind faith. There is no proof of God; therefore, it is unreasonable to believe in God.

The diagnosis was immediate: Masses matting the lungs and deforming the spine. Cancer. In my neurosurgical training, I had reviewed hundreds of scans for fellow doctors to see if surgery offered any hope. I'd scribble in the chart 'Widely metastatic disease - no role for surgery,' and move on. But this scan was different: It was my own.

The tricky part of illness is that, as you go through it, your values are constantly changing... You may decide you want to spend your time working as a neurosurgeon, but two months later, you may want to learn to play the saxophone or devote yourself to the church. Death may be a one-time event, but living with terminal illness is a process.

What patients seek is not scientific knowledge that doctors hide, but existential authenticity each person must find on her own... the angst of facing mortality has no remedy in probability.

Time for me is double-edged: every day brings me further from the low of my last cancer relapse, but every day also brings me closer to the next cancer recurrence - and eventually, death. Perhaps later than I think, but certainly sooner than I desire.

I had spent so much time studying literature at Stanford and the history of medicine at Cambridge in an attempt to better understand the particularities of death, only to come away feeling like they were still unknowable to me.

People react differently to hearing 'Procedure X has a 70 percent chance of survival' and 'Procedure Y has a 30 percent chance of death.' Phrased that way, people flock to Procedure X, even though the numbers are the same.

While all doctors treat diseases, neurosurgeons' work is the crucible of identity. Every operation on the brain is, by necessity, a manipulation of the substance of our selves.