“Elementary, my dear Watson”

It is clearly the silly season in journal publication when distinguished researchers are speculating about the ultimate destiny of missing teaspoons from their own departments.1 In spite of the dearth of published work on this topic, one has to wonder whether the overly scientific longitudinal cohort study was the best means of studying this phenomenon.

In 19th century medicine, the art of clinical reasoning was held to be as important as the scientific aspects of medical practice. I was reminded of this at the recent BASEM meeting in Edinburgh when Dr Donald Macleod gave the Roger Bannister Oration. He referred to one of the distinguished sons of Edinburgh, Joseph Bell, who was professor of surgery at Edinburgh Medical School and the basis for the character of Sherlock Holmes.

Although the history of detective literature conventionally dates back to 1841, when The Murders in the Rue Morgue by Edgar Allan Poe was published, Holmes is widely considered the doyen of such consulting detectives.

During their golden age of the 19th century, both of the disciplines thrived on a faith based on their methods of interpretation of clues (by detectives) or understanding of signs and symptoms (by physicians). A final “diagnosis” was then reached by clues that were often meaningless to the layman. The amazement that Sherlock Holmes excites when he guesses through apparently insignificant details that Watson has been to send a telegram from the Wigmore Street post office in The Sign of the Four is similar to the reaction Dr Trousseau gets when he diagnoses meningitis by scratching a patient’s skin.2,3

In The Sign of Four, Sherlock Holmes states that three qualities are necessary for the ideal detective: …