Montaigne wrote that having death present, constitutes by itself, an act to break free from her; the essay writer adds that “[…] imagining it before hand, assumes without a doubt, a great advantage” (^{Montaigne 2010, 130}). As a physician as he was, Oliver Sacks had no problem with doing such exercise. Physicians are always close to death.¹ However, they not only imagine it, but they frequently meet her in their day-by-day lives: they fight it, and -in other cases- they try to comfort their patients, in order to cope with it in the best way.

In Gratitude, Sacks describes three passages of his life, in which he visualized his own death. The first one happened when he was practicing mountaineering, when he was forty-one years old; then, he turned to provide himself with first aid. He briefly describes this experience in the first essay of the book, which gives us a first signal of his closeness with chemistry right from his name: “Mercury”. Also in “Mercury”, the author transmits his uneasiness in face of the proximity of this eightieth birthday, because the physical deterioration has collected a toll and the loss -of people very close to him- is very much present. In third place, “Of my own life” is the text through which he shares his feelings when seeing death face to face (p.28). He wrote it after finding out that he had liver cancer, secondary to a metastasis generated by an ocular melanoma, which he had been diagnosed in 2005.

The author expresses that the three moments were accompanied by a retrospection on his life and, even more, for love for what had been lived. For that, he could place in the physician’s pen, what was written by Etty Hillesum: “I have come to terms with life” (^{Hillesum 2007, 118}). There lies the reason of his last essay, where he discovers himself thinking about a deep-rooted Jewish tradition, despite of his separation from the religion since he was eighteen years old. I am referring to the Sabbath: when you have the feeling that your job is done and that, with a clean conscience, you can rest (p. 61)

Without planning that objective, Sacks gives us his clue to achieve a plentiful life, which would comfort us in face of the emotional distress of death: to have passions that we would enjoy until our last day.

Swimming was one of them. He practiced it since his father took him to have “contact with water before even to be one week old” (^{Sacks 1997}). He kept doing it even after finding out about his metastasis, every day but more… slowly (p.41).

Since his first decade, the elements of the periodic chart, “became my companions” (p.38), he said. Then, he started to relate them with his anniversaries, when he found out what the atomic numbers where (p.17).

He also verifies that he was not mistaken by choosing medicine as a career, because he took the time to visit patients (p. 40) even after the embolization that was performed on him. Furthermore, his work as a physician helped him to overcome the personal crisis he endured in the 1960’s decade.

His beginnings in writing were linked to medicine; although, by means of the story telling about his patients at the Bronx hospital, he discovered his vocation and he rendered himself to it in body and soul, with full determination (p.54). This book is the most tangible mirror image: he wrote, up until the closest days to his departure.

It is not a coincidence, to see in the photographs -together with the texts- Oliver Sacks swimming, reading and writing; as well as, a small gathering of objects on a table, that (I imagine) are part of the collection of chemical elements.

I don’t know if he had the chance to die under the celestial glares (p. 37), as he wanted; but it comforts me to know that he was surrounded, the same as when he was a little child, of metals and minerals, small insignia of eternity (p.39).

The set of essays, which form this piece of work, were written and published in different dates; but the selection of the same, achieves a theme unity over the worries not exclusive of a physician, but by every men: death. It is not by chance that the first text that came to my mind when reading them was about how to philosophize is to learn to die, by Montaigne, the essayist of the human condition. I confirmed the relationship between the two works by going through the pages of Gratitude, where I learned that Sacks was accompanied by the teachings he discovered through the reading of David Hume, one of my favorite philosophers (p.28), he confessed.

At every moment, it was evident when reading, the prose that characterized Sacks. It flows, as a product -maybe- of his ability in the water; after all, many of his writings were thought while he was swimming.² Sensitivity has presence that it can only be the result of the strong relationships that he gathered. We perceive the references of an emphatic reader, as of the letters as well as of the facts.

For those who have not read Sacks yet, Gratitude is a brief approximation to his work and allows visualizing the intensity of his life.³ The book is an opportunity to get closer to the writing of whom Borges could have well called the greatest writer of all physicians,⁴ while for his constant readers, Oliver leaves in Gratitude an endearing farewell.

The man, whose favorite plants were rarely the ferns,⁵ would have had to share the two characteristics for which he had marveled with them:

Beauty “[…] are a simple form of life, but they have their own beauty, a very delicate beauty” (^{Sacks 2005}), and the survival: “They are great survivors” (^{Sacks 2005}).

The first one is reflected in his very fruitful life; the second one is a product of his work. I am very glad to be an accomplice in achieving such permanence, which was -at the same time- one of his wishes: I only have the expectation to endure in the memory of friends, an of that some of my books can remain «speaking» to people after my death (p.20).