It is of the highest importance in the art of detection to be able to recognize, out of a number of facts, which are incidental and which vital.
—"The Adventure of the Reigate Squire"
One hallmark of the Memoirs is the discernible effort to invest a modicum of humanity into the persona of Sherlock Holmes. Whether through his more winsome, philosophical outlook in “The Cardboard Box,” his fallibility and genuine emotional rapprochement of his own arrogance in “The Yellow Face,” or his nostalgic look at his personal history in both “Gloria Scott” and “The Musgrave Ritual.” We, as readers, know more about Holmes in these cases than previous ones, and, as such, feel like we know Holmes better as a result. A more human Holmes still manages to astound and astonish but does so as more man than machine, allowing the reader to relate, and, thus, savor the deductions all the more. But a human Holmes is a mortal creature and Conan Doyle spares neither the reader nor his protagonist in demonstrating this fact. Holmes’s struggles with addiction and rapid cycling of mood are notable in many of the Adventures and allusions to the latter make an unwelcome return in “The Adventure of the Reigate Squire,” a tale of blackmail, jealousy and murder made all the more disturbing via the personal connection Watson has with their host, Colonel Hayter.
As “Reigate Squire” opens, Holmes is in France, just having completed a case that has won him no small amount of notoriety, but also showing all the signs of nervous exhaustion. Watson recounts disturbances in his sleep cycle as well as fluctuations in mood, resulting in the detective falling “prey to the blackest depression.” Watson is quick to place blame for the malady on “the strain caused by his immense exertions in the spring of ’87,” but none of these cases are recorded by Watson, save mentions of the“question of the Netherland-Sumatra Company and of the colossal schemes of Baron Maupertuis.” In fact, as Sherlockians William Baring-Gould and Ernest Bloomfield Zeisler noted, “Reigate Squire” is, chronologically, the first case in 1887 recounted by Watson, and the only one in the canon taking place in the spring. Three cases are recorded that summer (“The Second Stain” and “The Naval Treaty” in July, and “The Crooked Man” in August) followed by two that autumn (“The Five Orange Pips” in September, and “The Noble Bachelor” in October). Only one is recorded by Watson (“The Veiled Lodger,” in September) from the year before. The vicissitudes of chronology and Watson’s selective narration force the reader to either place a significant amount of emphasis on either stories mentioned but not recorded by Watson, or an unknown quantity of cases occurring in the spring of 1887 as particularly detrimental to Holmes’s health or, rather, simply an environmental trigger for a chronic or malingering condition exacerbated more than usual that spring.
Perhaps the most convincing evidence that the reader has that Holmes’s nervous illness is chronic is the way in which Holmes uses it to his advantage in “The Reigate Squire,” as he convincingly blurs the line between a feigned condition and an actual one. The success—one shared by both Holmes and Conan Doyle—is the convincing way it is described, as lauded by neuroscientists Terence L Riley and Alec Roy in their 1982 textbook Pseudoseizures. As to what the malady may be, on this fact, Conan Doyle, Watson, and Holmes are silent, and the reader is left, uncharacteristically, in the dark.