“Living has yet to be generally recognized as one of the arts,” proclaimed a 1924 guide to the art of living. That one of the greatest scientists of our time should be one of our greatest teacher in that art is nothing short of a blessing for which we can only be grateful — and that’s precisely what Oliver Sacks (July 9, 1933–August 30, 2015), a Copernicus of the mind and a Dante of medicine who turned the case study into a poetic form, became over the course of his long and fully lived life.

In his final months, Dr. Sacks reflected on his unusual existential adventure and his courageous dance with death in a series of lyrical New York Times essays, posthumously published in the slim yet enormously enchanting book Gratitude (public library), edited by his friend and assistant of thirty years, Kate Edgar, and his partner, the writer and photographer Bill Hayes.

In the first essay, titled “Mercury,” he follows in the footsteps of Henry Miller, who considered the measure of a life well lived upon turning eighty three decades earlier. Dr. Sacks writes:

Last night I dreamed about mercury — huge, shining globules of quicksilver rising and falling. Mercury is element number 80, and my dream is a reminder that on Tuesday, I will be 80 myself. Elements and birthdays have been intertwined for me since boyhood, when I learned about atomic numbers. At 11, I could say “I am sodium” (Element 11), and now at 79, I am gold. […] Eighty! I can hardly believe it. I often feel that life is about to begin, only to realize it is almost over.

Having almost died at forty-one while being chased by a white bull in a Norwegian fjord, Dr. Sacks considers the peculiar grace of having lived to old age:

At nearly 80, with a scattering of medical and surgical problems, none disabling, I feel glad to be alive — “I’m glad I’m not dead!” sometimes bursts out of me when the weather is perfect… I am grateful that I have experienced many things — some wonderful, some horrible — and that I have been able to write a dozen books, to receive innumerable letters from friends, colleagues and readers, and to enjoy what Nathaniel Hawthorne called “an intercourse with the world.” I am sorry I have wasted (and still waste) so much time; I am sorry to be as agonizingly shy at 80 as I was at 20; I am sorry that I speak no languages but my mother tongue and that I have not traveled or experienced other cultures as widely as I should have done.

But pushing up from beneath the wistful self-awareness is Dr. Sacks’s fundamental buoyancy of spirit. Echoing George Eliot on the life-cycle of happiness and Thoreau on the greatest gift of growing older, he writes:

My father, who lived to 94, often said that the 80s had been one of the most enjoyable decades of his life. He felt, as I begin to feel, not a shrinking but an enlargement of mental life and perspective. One has had a long experience of life, not only one’s own life, but others’, too. One has seen triumphs and tragedies, booms and busts, revolutions and wars, great achievements and deep ambiguities, too. One has seen grand theories rise, only to be toppled by stubborn facts. One is more conscious of transience and, perhaps, of beauty. At 80, one can take a long view and have a vivid, lived sense of history not possible at an earlier age. I can imagine, feel in my bones, what a century is like, which I could not do when I was 40 or 60. I do not think of old age as an ever grimmer time that one must somehow endure and make the best of, but as a time of leisure and freedom, freed from the factitious urgencies of earlier days, free to explore whatever I wish, and to bind the thoughts and feelings of a lifetime together.

In another essay, titled “My Own Life” and penned shortly after learning of his terminal cancer diagnosis at the age of eighty-one, Dr. Sacks reckons with the potentiality of living that inhabits the space between him and his death:

It is up to me now to choose how to live out the months that remain to me. I have to live in the richest, deepest, most productive way I can. In this I am encouraged by the words of one of my favorite philosophers, David Hume, who, upon learning that he was mortally ill at age 65, wrote a short autobiography in a single day in April of 1776. He titled it “My Own Life.” “I now reckon upon a speedy dissolution,” he wrote. “I have suffered very little pain from my disorder; and what is more strange, have, notwithstanding the great decline of my person, never suffered a moment’s abatement of my spirits. I possess the same ardour as ever in study, and the same gaiety in company.”

Gliding his mind’s eye over one of Hume’s most poignant lines — “It is difficult to be more detached from life than I am at present.” — Dr. Sacks considers the paradoxical way in which detachment becomes an instrument of presence:

Over the last few days, I have been able to see my life as from a great altitude, as a sort of landscape, and with a deepening sense of the connection of all its parts. This does not mean I am finished with life. On the contrary, I feel intensely alive, and I want and hope in the time that remains to deepen my friendships, to say farewell to those I love, to write more, to travel if I have the strength, to achieve new levels of understanding and insight.

Such intensity of aliveness, Dr. Sacks observes, requires a deliberate distancing from the existentially inessential things with which we fill our daily lives — petty arguments, politics, the news. With his characteristic mastery of nuance, he points to a crucial distinction:

This is not indifference but detachment — I still care deeply about the Middle East, about global warming, about growing inequality, but these are no longer my business; they belong to the future. I rejoice when I meet gifted young people — even the one who biopsied and diagnosed my metastases. I feel the future is in good hands.

Decades after his beloved aunt Lennie taught him about dying with dignity and courage, Dr. Sacks lets this lesson come abloom in his own life. True to the defining enchantment of his books, he turns his luminous prose inward, then outward, and in a passage that calls to mind William Faulkner’s sublime living obituary, he exits this world — the world of writing and the world of life, for the two were always one for Dr. Sacks — with a breathtaking epitaph for himself:

I cannot pretend I am without fear. But my predominant feeling is one of gratitude. I have loved and been loved; I have been given much and I have given something in return; I have read and traveled and thought and written. I have had an intercourse with the world, the special intercourse of writers and readers. Above all, I have been a sentient being, a thinking animal, on this beautiful planet, and that in itself has been an enormous privilege and adventure.

Gratitude is a bittersweet and absolutely beautiful read in its entirety. Complement it with Dr. Sacks on the life-saving power of music, the strange psychology of writing, and his story of love, lunacy, and a life fully lived, then revisit my remembrance of Dr. Sacks’s singular spirit.