October 4, 2011

Lessons from Sherlock Holmes: Trust in The Facts, Not Your Version of Them

When we look around us, what is it that we see? Do we see things as they are, or do we at once, without thinking, begin to interpret? Take the simple example of a wine glass.

By Maria Konnikova

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American

When we look around us, what is it that we see? Do we see things as they are, or do we at once, without thinking, begin to interpret? Take the simple example of a wine glass. All it is is a transparent object that holds a liquid–which we know by experience should be wine. But if we’re in a store and late for a party? It’s a present, an object of value and beauty for someone else to appreciate. At home and thirsty? It becomes, perhaps, a water glass, if nothing else is available. Bored? A toy to turn around and around, seeing what reflections we can see, how we can distort our own face on the curved surfaces. Solving a murder? Potential evidence of some final, telling pre-death interaction–perhaps the victim took a final sip before he met an untimely end.

Soon, instead of saying there is a wine glass on the table, you say the victim’s glass had been empty at the time of the crime. And you proceed from there. Why was the victim drinking? Why was he interrupted? Why had he placed the glass where it was? And if it doesn’t make sense? Impossible. You’ve started with a fact and worked your way forward. It must fit. The only thing is, you’ve forgotten that it was just a glass to begin with. The victim’s? Maybe not. Placed there by him? Who knows. Empty at the time of the crime? Perhaps, but perhaps not. You’ve imbued an object with a personal take so naturally that you don’t realize you’ve done it. And that’s the crucial–and sometimes fatal–error, of both reasoning and world perception. A pipe is never just a pipe.

Hardly ever, in describing an object, do we see it as just a valueless, objective wine glass. And hardly ever do we think to consider the distinction–for of course, it hardly ever matters. But it’s the rare mind that has trained itself to separate the objective fact from the immediate, subconscious and automatic subjective interpretation that follows.

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In “The Adventure of the Priory School,” a valuable young pupil goes missing from boarding school and Sherlock Holmes is called in to help solve the disappearance. In his search for the young man, Holmes comes across the dead body of the German schoolmaster who had vanished on the same night as the boy. Before proceeding further with the inquiry, he stops to enumerate to Watson everything that he has already discovered.

“Let us continue our reconstruction. He meets his death five miles from the school–not by a bullet, mark you, which even a lad might conceivably discharge, but by a savage blow dealt by a vigorous arm. The lad, then, had a companion in his flight. And the flight was a swift one, since it took five miles before an expert cyclist could overtake them. Yet we surveyed the ground round the scene of the tragedy. What do we find? A few cattle tracks, nothing more. I took a wide sweep round, and there is no path within fifty yards. Another cyclist could have had nothing to do with the actual murder, nor were there any human foot-marks.”

“Holmes,” I cried, “this is impossible.”

“Admirable!” he said. “A most illuminating remark. It is impossible as I state it, and therefore I must in some respect have stated it wrong. Yet you saw for yourself. Can you suggest any fallacy?’

Instead, Watson suggests that they give up altogether. “I am at my wit’s end,” he says. “Tut, tut,” scolds Holmes. “We have solved some worse problems. At least we have plenty of material, if we can only use it.”

In this brief exchange, Watson does two things: he objects to the impossibility of someone attacking the cyclist absent tracks, and he suggests that the difficulty is an insurmountable one. On the first point, Holmes applauds him (however facetiously) but on the second, he reprimands him. Why? What’s going on?

Learning to trust the facts: If anything is wrong, it’s you

Holmes’s initial response to Watson’s skepticism would do better to be accented not on the is, but on the as I state it. That, in essence, is the difference between his reaction and Watson’s: to Watson, the case is impossible, to Holmes, it is impossible as stated–meaning that something must be wrong, not in the observations themselves, but in the way they are being framed.

Where is Watson going wrong? He is equating the initially observed facts with their statement, and concluding that the facts are impossible because the statement is so. But the two are not one and the same. The statement is just one possible view of the observations; somewhere, that view may have gone astray, even when the observer is Sherlock Holmes himself. And Holmes recognizes this, even if Watson does not. When the battle is between objective facts and subjective interpretation, the former wins out. Trust too much to the latter, and you may end up by undermining the integrity of the former.

But like Watson, it is something that we are all too prone to do. Often, our mind conflates the world and our own interpretation of it without much thought. We simply assume that the way we see is the way it is. And once that way is verbalized, put into specific words with specific meanings, it becomes all the more difficult to parse. It’s Shakespeare’s “thinking makes it so” at the most basic level: not giving a value judgment, but even before that, imagining the world to be a specific way because that is how you thought it was.

Holmes knows better. He knows that the error is with him and not with the observational inputs. If it’s impossible, it doesn’t meant it’s time to give up. It means that his mind somewhere went wrong, did not interpret something properly, did not see something that was there or think of something that could have been thought of. The options are never exhausted, not really. What may be lacking is imagination or that moment of insight–but not the facts themselves. If the German schoolmaster was murdered, he was murdered, even absent any obvious tracks.

Of course, Holmes will later discover that the cow was not a cow at all, and the cattle tracks, nothing at all what they seemed. Then, it will all come together. But to get to that point, he must not give up as easily as Watson would have him do. He must trust in his observations, if not yet in his imagination or his deduction, and not give up in the face of what is at first glance impossible.

Watson would have never gotten that far. Neither would any number of the detectives from Scotland Yard who cross Holmes’s path, who are always a bit too quick to assume that “I haven’t thought of a way to make it possible” is the same thing as “is in fact impossible.”

Trust the evidence. It won’t lie. What will is your mind, your way of seeing, and your ability to discern the truth from what you observe.

Photo credit: Holmes and Watson find the dead cyclist in “The Adventure of the Priory School.” By Sidney Paget (1860 – 1908) (Strand Magazine) [Public domain], via Wikimedia Commons.

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