It’s only partly a figure of speech to say that John Harley Warner, Ph.D., lives surrounded by books. To meet with him, a visitor first ascends to a second-floor balcony that overlooks the book collection of the School of Medicine’s Harvey Cushing/John Hay Whitney Medical Historical Library. Then, a walkway to a door built directly into the stacks opens into Warner’s office, which is filled with floor-to-ceiling bookcases of its own. It is a fitting perch for Warner, Avalon Professor of the History of Medicine and chair of the School of Medicine’s Section on the History of Medicine.

Warner, whose demeanor is also bookish, and is marked by the reserve of many scholars in the humanities, originally planned to become a scientist. But in college, a late-night conversation over coffee with a friend about The Two Cultures, British physicist/novelist C.P. Snow’s classic 1959 lament on the divide between the sciences and the humanities, opened his eyes to a new path. “‘People think about this?’” Warner recalls asking himself. “I really hadn’t realized that such a field existed.”

He went on to graduate training with Barbara G. Rosenkrantz, Ph.D., professor of the history of science (now emerita) at Harvard University, and became interested in the changing identities of medical practitioners of the 19th century—how were physicians’ views of themselves and their profession transformed in that rapidly changing world?

“What historians are good at is messiness,” Warner says. “In some ways we’re better as cultural critics in getting people to ask questions, and to reflect, than we are as boosters.”

These concepts inform much of Warner’s research, including his major 1998 work Against the Spirit of System: The French Impulse in Nineteenth-Century American Medicine, which is rooted in the diaries, letters, and clinical notes of young American doctors studying medicine in early-1800s Paris—then the center of cutting-edge science—who returned to America armed with new knowledge and perspectives.

Generally, Western medicine had inherited “theoretically complex, very rationalistic” medical systems from the Enlightenment, Warner says. But in Paris, American doctors saw an opportunity for systematic change that could “socially and culturally uplift the medical profession in the United States.” They could now “ignore things they saw as literally irrelevant, because they didn’t have any purchase on the real world,” instead focusing on the patient at the bedside and at the body at autopsy, and making correlations between the two.

“Observe and describe, don’t go beyond that,” is how Warner describes this new outlook. “It really is the origin of the American kind of clinical, hospital-based medicine, and the idea that the hospital should be a place for research as well as practice that takes shape as a consequence,” profoundly changing the profession and doctors’ identity in the process.

Warner is now working on a book-length study of James Jackson Jr., M.D., a young American doctor who apprenticed in a Paris hospital in the early 1800s, making use of his “wonderfully rich” weekly correspondence with his father, a Harvard professor and one of the founders of Massachusetts General Hospital. Another current research project is a study of the transformations of the hospital patient chart from the 19th to 21st centuries.

In this year of the School of Medicine’s Bicentennial, Warner says, one could argue it is the notion of identity that now sets the medical school apart. Before the 1910s and the philanthropic infusion of funds that made reform possible, Yale’s medical school “resembled a trade school,” as was typical of American medical schools at the time. And with the establishment in the 1920s of the Yale System of medical education, which respects students’ independence, “Yale took a very brave, controversial, and consequential step,” he says, to “treat medical students as adults, as grown-ups, as graduate students—as people who could have an active role in shaping … what kind of doctors they became.”