They all agreed that it was a huge creature, luminous, ghastly, and spectral. I have cross-examined these men, one of them a hard-headed countryman, one a farrier, and one a moorland farmer, who all tell the same story of this dreadful apparition, exactly corresponding to the hell-hound of the legend.

Dr. Mortimer tells Holmes that there have been several incidents regarding the case that have been hard to “reconcile with the settled order of Nature.” Dr. Mortimer cites the accounts of several inhabitants of the moor—a countryman, a farrier, and a farmer—who all testify that they saw a huge creature, spectral in nature, that can’t be identified by science. For Dr. Mortimer, these eyewitness accounts are enough to convince him of the curse—and they may present a strong case for the reader as well—but the accounts are not enough to convince Holmes.

And you, a trained man of science, believe it to be supernatural?

Interestingly, a doctor, a man of science, brings the Baskerville case to Holmes, as despite his education and profession, he believes in the curse. Dr. Mortimer has intimate ties to the case—he knew about Sir Charles Baskerville’s heart condition, and he read the newspaper accounts and the eighteenth-century account of the family curse. Here, Holmes ask Dr. Mortimer point-blank if he believes in the supernatural. Throughout the novella, the characters struggle between fact and fiction, and Dr. Mortimer, being a man of science yet an inhabitant of the moor, represents an interesting blend of skeptic and believer.

Yes, it is an interesting instance of a throw-back, which appears to be both physical and spiritual. A study of family portraits is enough to convert a man to the doctrine of reincarnation. This fellow is a Baskerville—that is evident.

When Holmes catches a glance of a portrait of Sir Hugo Baskerville, whose legendary wickedness gave birth to the curse of the hound, Holmes immediately notices an uncanny resemblance between Hugo and Mr. Stapleton. Watson agrees. Holmes clearly doesn’t believe in life after death, but his offhand statement tying Mr. Stapleton’s evilness to Sir Hugo’s serves as intriguing bait for the reader: His comment offers a metaphysical explanation that seems plausible and certainly seems more interesting than a purely logical one.

“Phosphorus,” I said. “A cunning preparation of it,” said Holmes, sniffing at the dead animal.

Holmes’s faith in real-world, logical explanations for the circumstances of the case as they develop throughout the plot never wavers. Conan Doyle creates many opportunities for both characters and readers to believe in the curse—understandably so, since Mr. Stapleton designed his ruse to that purpose. In the end, though, Holmes is proven right: The curse isn’t real, and the hound examined in this quote was gussied up with phosphorus to give the creature a supernatural appearance.

The devil’s agents may be of flesh and blood, may they not?

As Holmes and Watson discuss the case, Holmes notes that the moor, indeed, seems to be a “wild place” and that if the devil were in fact involved, the moor would be an ideal location. Here, after Watson asks Holmes if he then believes in the curse, Holmes replies with a rhetorical question suggesting that one doesn’t necessarily need to believe in a curse to believe that evil exists in the hearts of human beings. Holmes’s quick answer deftly conflates two seemingly incompatible ideas: a belief in evil and a belief in the reality of nature.