Hoonhout performed research within the archives of the Royal College of Surgeons of England and at Kings College London, studying 19th-century English physician Joseph Henry Green.

Through reading the physician’s books, essays, and letters, he learned of Green’s biography, academic interests, and career achievements, including an assortment of philosophical work—which may have influenced the medical field at the time. Reading Green’s debates about human anatomy, evolution, medical reform, and philosophy showed Hoonhout how past physicians viewed the medical profession; his own desire to pursue medicine has only been reaffirmed as he synthesizes his research discoveries.