Background Most studies on medical reasoning focus on contemporary allopathic practitioners. Here, the significance of diagnostic sense in Nizāmī ‘Arūzī’s Four Discourses (Chahār Maqāle), an influential text that circulated widely throughout the Islamic world, is explored.

Methods After a brief introduction, key passages are translated on how doctors should cultivate analytical skills.

Results Nizāmī ‘Arūzī cites three sources of diagnostic authority: (1) education in the texts of medical experts, (2) formal logic and (3) belief in the power of God.

Conclusions ‘Arūzī’s methods, though rooted in a religious faith that may seem foreign to contemporary doctors and educators, has much to recommend regarding its clarity of approach, its high ethical standards and expectations of doctors, and its commitment to best practices for the patient. Crosscultural studies of medical education and professionalism can offer valuable insights by demonstrating how doctors across history and geography have grappled with the common concerns of diagnosis and treatment.