Perhaps it is not Sherlock Holmes's brain that so impresses us, but his vision. Holmes may have been blessed with the finest set of peepers in the land. It is not odd, of course, that an ophthalmologist would write about an uncommonly good set of eyes. Though he would sometimes have Holmes use a lens, clearly Conan Doyle thought that Holmes could see more and better than the rest of the world.
Holmes treated his eyes well. He knew they were his greatest gift and not to be trifled with. He couldn't even be bothered to waste them for routine tasks such as checking his own references; often he makes Watson read aloud from his index or from works such as Bradshaw. Only a man who was blind or illiterate would do this regularly, unless he was saving his eyes for more important things. Consider the many times Holmes uses the phrase "lose sight" or "lost sight." Holmes, always a diva, must have fretted about vision more than a singer does about her throat.
Of course Holmesówho had never seen with any eyes but his ownócautioned Watson, in "A Scandal in Bohemia," "You see, but you do not observe." We've always thought the emphasis was on "observe," but Holmes surely put it on the "you." Watson's vision was not Holmes's. Holmes was aware that something was different about his vision. One day, perhaps, we shall all be granted the gift to see the world through Holmes's eyes. Until then, we must accept that our sight is always a bit cloudier than it might be.
The Editor's Gas-Lamp, Autumn 2016, Vol. 66, No. 3.