Oliver Sacks wanted to be a “real scientist” — someone who worked in a lab and conducted experiments and submitted studies to academic journals.

But as the 81-year-old approaches the end of his career and his life, he will likely be remembered for his work as a writer rather than as a researcher. Nowhere is that more apparent than in the thousands of online reactions to an essay Sacks published in the New York Times on Thursday announcing that a cancer diagnosed in 2005 has metastasized in his liver, leaving him with months to live.

The essay was tweeted by writers John Green, Neil Gaiman, Susan Orlean and Joyce Carol Oates, actress Marlee Matlin, dozens of journalists and thousands of people far outside of the scientific community.

“Beautiful, eloquent statement….but so sad,” tweeted Oates. “‘Everything ends too soon.'”

“Just read about your terminal diagnosis but am so inspired by your words — as always,” tweeted Matlin. 

“What a heartbreaking and beautiful read from a hero,” said Atul Gawande, also a physician and author of “Being Mortal.”

The breadth of the response is a testament to the impact of Sacks’s books, which dramatize his experiences working with patients with neurological conditions.

“Oliver Sacks is a great includer,” science journalist Robert Krulwich said in a 2013 episode of his NPR show “Radiolab.” “His descriptions in all these books are so full of feeling he makes [his subjects] come alive. This is his legacy.”

Inspired by the 19th century tradition of writing “clinical anecdotes,” Sacks’s 12 books dramatize his research in precise yet lyrical language. They are rich with narrative detail, as focused on what it feels like to live with a neurological condition as characteristics of the diseases themselves, and easily lend themselves to adaptations as plays, movies and, in one case, an hour-long opera.

In the “Radiolab” interview, Sacks said he never planned to become a writer. But after failing as a researcher at Yeshiva Univesity’s Einstein Medical Center, he was exiled to Beth Abraham Hospital, a nursing home in the Bronx. There he encountered a group of patients suffering from encephalitis lethargica, a decades-long sleeping sickness, who he was able to revive using a chemical called L-DOPA. Frustrated with medical journals’ focus on data and lab tests rather than “phenomenological description,” Sacks documented his findings in the 1973 book “Awakenings.”

The work garnered little interest in the neurological community — aside from criticism that what Sacks had written was mere anecdote rather than real research.

But readers and other writers loved it. The book became a bestseller, and the poet W. H. Auden called it a “masterpiece.” Sacks became even more of a household name after “Awakenings” was fictionalized in a 1990 movie starring Robin Williams. Williams, who played a Sacks-like neurologist, described the scientist as a combination of Arnold Schwarzenegger and Albert Schweitzer.

“The amazing thing is, as big as he is and as strong as he is, he’s this very gentle and compassionate man,” he said. “Who is brilliant.”

Sacks’s habit of turning his patients into protagonists — or, in some cases, secondary characters — has drawn criticism from scientists and activists. Riffing on the title of Sacks’s 1985 bestseller “The Man Who Mistook His Wife for a Hat,” geneticist and disability advocate Tom Shakespeare once called him “the man who mistook his patients for a literary career.”

But lately Sacks’s most frequent subject of scientific study has been himself. In “The Mind’s Eye,” a series of stories about patients with vision problems published in 2010, Sacks describes his treatment for ocular cancer with giddy intellectual interest. One scene depicts him confined to his hospital room while a radioactive chip is embedded in his cancerous eye, asking his nurse to bring him a set of fluorescent minerals for a potential experiment.

“Perhaps I could light them up by fixing my radioactive eye, my rays on them,” he wrote. “It would be quite a party trick!”

For the most part, Sacks’s descriptions of the diagnosis and treatment process have won praise for both their literary and scientific value. In a 2002 profile in Wired, Steve Silberman argued that the author’s emphasis on narrative was essential to a more complex understanding of the mind. Modern neurological tools, he said, have restricted scientists to viewing the brain as a straightforward machine and memories as mere “static files.”

“However, advancements in cognitive neuroscience have suggested that memories unfold across multiple areas of the cortex simultaneously, like a richly interconnected network of stories,” he wrote. “By restoring narrative to a central place in the practice of medicine, Sacks has regrafted his profession to its roots.”

Sacks’s New York Times essay is fittingly elegiac for the man who was once called the “poet laureate of contemporary medicine.” It’s full of his characteristic philosophical musings and sometimes clinical interest in a scientific phenomenon, even though that phenomenon is a cancerous tumor wreaking havoc on his body.

“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,” he wrote.

And despite the mournful response on Twitter, Sacks’s essay is firm that he is not done yet. “On the Move,” a memoir of his early career as a physician, is due out in May 2015, and he writes that he has several books nearly finished.

Priorities in order, he will no longer be paying attention to politics or arguing about global warming. “These are no longer my business; they belong to the future,” he wrote.

Instead, Sacks said he’ll be focusing on his work, his friendships and 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,” he wrote. “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.”

Correction: The original version of this story incorrectly stated that Robin Williams was nominated for an Academy Award for his performance in “Awakenings.” The film received an Oscar nomination, but Williams did not.