Chief Resident at Stanford University Paul Kalanithi was in his final year of neurosurgical residency when he was diagnosed with metastatic lung cancer. He grew to even greater prominence with his eloquent New York Times Essay, “How Long Have I Got Left?

Kalanithi soon went through the kind of grueling surgery that he’d long trained to help others through. To make it even more difficult: Just weeks after he came home from surgery his wife gave birth to their first child. A baby girl.

We’d originally thought of this as a big Get Well card for this great human being. We’re a relatively young website, but we do our best to find great people who do great things and that’s what drew us to him. Even after his diagnosis, when Kalanithi couldn’t even count on making it home from work, he still awoke every morning at 5:30. “I can’t go on,” he would say to himself, his wife still asleep. “And a minute later, I am in my scrubs, heading to the operating room, alive: ‘I’ll go on.’”

But Paul Kalanithi died today at 37.

It seems natural that a brilliant neurosurgeon with a gift for language might spend his remaining days writing to the daughter who might never know him. Just weeks ago, Kalanithi used his remaining strength to pen a brilliant, moving essay, “Before I Go.”

There are beautiful, life-affirming passages in the essay about time, the elements of surgery, his training, life and love. It’s a fascinating read.

But at the very end he writes the most perfect thing any man could leave for a daughter. No advice. No hopes or aspirations. Just this:

When you come to one of the many moments in life when you must give an account of yourself, provide a ledger of what you have been, and done, and meant to the world, do not, I pray, discount that you filled a dying man’s days with a sated joy, a joy unknown to me in all my prior years, a joy that does not hunger for more and more, but rests, satisfied. In this time, right now, that is an enormous thing.

Kalanithi won the Lewis H. Nahum Prize for outstanding research at Yale Medical before going on to Stanford.  When his old professor Sherwin B. Nulland—author of How We Die—passed, Paul Kalanithi wrote the perfect last words in the Paris Review.  “Condolences to Dr. Nuland, his family, and those who knew him. I hope he was one of the lucky few to find death with dignity. But I am glad that, until my own time comes, I have his voice in my head; and if I need an extended conversation, it is just a bookshelf away.”

Likewise, Doc.