Mastermind: How to Think Like Sherlock Holmes

by Maria Konnikova

  Who might this lady be? And what could she want with the detective? These questions form the starting point of The Sign of Four, an adventure that will take Holmes and Watson to India and the Andaman Islands, pygmies and men with wooden legs. But before any of that there is the lady herself: who she is, what she represents, where she will lead. In a few pages, we will examine the first encounter between Mary, Holmes, and Watson and contrast the two very different ways in which the men react to their visitor. But first, let’s take a step back to consider what happens in our mind attic when we first enter a situation—or, as in the case of The Sign of Four, encounter a person. How do those contents that we’ve just examined actually become activated?

  From the very first, our thinking is governed by our attic’s so-called structure: its habitual modes of thought and operation, the way in which we’ve learned, over time, to look at and evaluate the world, the biases and heuristics that shape our intuitive, immediate perception of reality. Though, as we’ve just seen, the memories and experiences stored in an individual attic vary greatly from person to person, the general patterns of activation and retrieval remain remarkably similar, coloring our thought process in a predictable, characteristic fashion. And if these habitual patterns point to one thing, it’s this: our minds love nothing more than jumping to conclusions.

  Imagine for a moment that you’re at a party. You’re standing in a group of friends and acquaintances, chatting happily away, drink in hand, when you glimpse a stranger angling his way into the conversation. By the time he has opened his mouth—even before he has even quite made it to the group’s periphery—you have doubtless already formed any number of preliminary impressions, creating a fairly complete, albeit potentially inaccurate, picture of who this stranger is as a person. How is Joe Stranger dressed? Is he wearing a baseball hat? You love (hate) baseball. This must be a great (boring) guy. How does he walk and hold himself? What does he look like? Oh, is he starting to bald? What a downer. Does he actually think he can hang with someone as young and hip as you? What does he seem like? You’ve likely assessed how similar or different he is from you—same gender? race? social background? economic means?—and have even assigned him a preliminary personality—shy? outgoing? nervous? self-confident?—based on his appearance and demeanor alone. Or, maybe Joe Stranger is actually Jane Stranger and her hair is dyed the same shade of blue as your childhood best friend dyed her hair right before you stopped talking to each other, and you always thought the hair was the first sign of your impending break, and now all of a sudden, all of these memories are clogging your brain and coloring the way you see this new person, innocent Jane. You don’t even notice anything else.

  As Joe or Jane start talking, you’ll fill in the details, perhaps rearranging some, amplifying others, even deleting a few entirely. But you’ll hardly ever alter your initial impression, the one that started to form the second Joe or Jane walked your way. And yet what is that impression based on? Is it really anything of substance? You only happened to remember your ex–best friend, for instance, because of an errant streak of hair.

  When we see Joe or Jane, each question we ask ourselves and each detail that filters into our minds, floating, so to speak, through the little attic window, primes our minds by activating specific associations. And those associations cause us to form a judgment about someone we have never even met, let alone spoken to.

  You may want to hold yourself above such prejudices, but consider this. The Implicit Association Test (IAT) measures the distance between your conscious attitudes—those you are aware of holding—and your unconscious ones—those that form the invisible framework of your attic, beyond your immediate awareness. The measure can test for implicit bias toward any number of groups (though the most common one tests racial biases) by looking at reaction times for associations between positive and negative attributes and pictures of group representatives. Sometimes the stereotypical positives are represented by the same key: “European American” and “good,” for instance, are both associated with, say, the “I” key, and “African American” and “bad” with the “E” key. Sometimes they are represented by different ones: now, the “I” is for “African American” and “good,” while “European American” has moved to the “bad,” “E” key. Your speed of categorization in each of these circumstances determines your implicit bias. To take the racial example, if you are faster to categorize when “European American” and “good” share a key and “African American” and “bad” share a key, it is taken as evidence of an implicit race bias.2

  The findings are robust and replicated extensively: even those individuals who score the absolute lowest on self-reported measures of stereotype attitudes (for example, on a four-point scale ranging from Strongly Female to Strongly Male, do you most strongly associate career with male or female?) often show a difference in reaction time on the IAT that tells a different story. On the race-related attitudes IAT, about 68 percent of over 2.5 million participants show a biased pattern. On age (i.e., those who prefer young people over old): 80 percent. On disability (i.e., those who favor people without any disabilities): 76 percent. On sexual orientation (i.e., those who favor straight people over gay): 68 percent. On weight (i.e., those who favor thin people over fat): 69 percent. The list goes on and on. And those biases, in turn, affect our decision making. How we see the world to begin with will impact what conclusions we reach, what evaluations we form, and what choices we make at any given point.

  This is not to say that we will necessarily act in a biased fashion; we are perfectly capable of resisting our brains’ basic impulses. But it does mean that the biases are there at a very fundamental level. Protest as you may that it’s just not you, but more likely than not, it is. Hardly anyone is immune altogether.

  Our brains are wired for quick judgments, equipped with back roads and shortcuts that simplify the task of taking in and evaluating the countless inputs that our environment throws at us every second. It’s only natural. If we truly contemplated every element, we’d be lost. We’d be stuck. We’d never be able to move beyond that first evaluative judgment. In fact, we may not be able to make any judgment at all. Our world would become far too complex far too quickly. As William James put it, “If we remembered everything, we should on most occasions be as ill off as if we remembered nothing.”

  Our way of looking at and thinking about the world is tough to change and our biases are remarkably sticky. But tough and sticky doesn’t mean unchangeable and immutable. Even the IAT, as it turns out, can be bested—after interventions and mental exercises that target the very biases it tests, that is. For instance, if you show individuals pictures of blacks enjoying a picnic before you have them take the racial IAT, the bias score decreases significantly.

  A Holmes and a Watson may both make instantaneous judgments—but the shortcuts their brains are using could not be more different. Whereas Watson epitomizes the default brain, the structure of our mind’s connections in their usual, largely passive state, Holmes shows what is possible: how we can rewire that structure to circumvent those instantaneous reactions that prevent a more objective and thorough judgment of our surroundings.

  For instance, consider the use of the IAT in a study of medical bias. First, each doctor was shown a picture of a fifty-year-old man. In some pictures, the man was white. In some, he was black. The physicians were then asked to imagine the man in the picture as a patient who presented with symptoms that resembled a heart attack. How would they treat him? Once they gave an answer, they took the racial IAT.

  In one regard, the results were typical. Most doctors showed some degree of bias on the IAT. But then, an interesting thing happened: bias on the test did not necessarily translate into bias in treating the hypothetical patient. On average, doctors were just as likely to say they would prescribe the necessary drugs to blacks as to whites—and oddly enough, the more seemingly biased physicians actually treated the two groups more equally than the less biased ones.

 
; What our brains do on the level of instinct and how we act are not one and the same. Does this mean that biases disappeared, that their brains didn’t leap to conclusions from implicit associations that occurred at the most basic level of cognition? Hardly. But it does mean that the right motivation can counteract such bias and render it beside the point in terms of actual behavior. How our brains jump to conclusions is not how we are destined to act. Ultimately, our behavior is ours to control—if only we want to do so.

  What happened when you saw Joe Stranger at the cocktail party is the exact same thing that happens even to someone as adept at observation as Mr. Sherlock Holmes. But just like the doctors who have learned over time to judge based on certain symptoms and disregard others as irrelevant, Holmes has learned to filter his brain’s instincts into those that should and those that should not play into his assessment of an unknown individual.

  What enables Holmes to do this? To observe the process in action, let’s revisit that initial encounter in The Sign of Four, when Mary Morstan, the mysterious lady caller, first makes her appearance. Do the two men see Mary in the same light? Not at all. The first thing Watson notices is the lady’s appearance. She is, he remarks, a rather attractive woman. Irrelevant, counters Holmes. “It is of the first importance not to allow your judgment to be biased by personal qualities,” he explains. “A client is to me a mere unit, a factor in a problem. The emotional qualities are antagonistic to clear reasoning. I assure you that the most winning woman I ever knew was hanged for poisoning three children for their insurance-money, and the most repellent man of my acquaintance is a philanthropist who has spent nearly a quarter of a million upon the London poor.”

  But Watson won’t have it. “In this case, however—” he interrupts.

  Holmes shakes his head. “I never make exceptions. An exception disproves the rule.”

  Holmes’s point is clear enough. It’s not that you won’t experience emotion. Nor are you likely to be able to suspend the impressions that form almost automatically in your mind. (Of Miss Morstan, he remarks, “I think she is one of the most charming young ladies I ever met”—as high a compliment from Holmes as they come.) But you don’t have to let those impressions get in the way of objective reasoning. (“But love is an emotional thing, and whatever is emotional is opposed to that true cold reason which I place above all things,” Holmes immediately adds to his acknowledgment of Mary’s charm.) You can recognize their presence, and then consciously cast them aside. You can acknowledge that Jane reminds you of your high school frenemy, and then move past it. That emotional luggage doesn’t matter nearly as much as you may think it does. And never think that something is an exception. It’s not.

  But oh how difficult it can be to apply either of these principles—the discounting of emotion or the need to never make exceptions, no matter how much you may want to—in reality. Watson desperately wants to believe the best about the woman who so captivates him, and to attribute anything unfavorable about her to less-than-favorable circumstances. His undisciplined mind proceeds to violate each of Holmes’s rules for proper reasoning and perception: from making an exception, to allowing in emotion, to failing altogether to attain that cold impartiality that Holmes makes his mantra.

  From the very start, Watson is predisposed to think well of their guest. After all, he is already in a relaxed, happy mood, bantering in typical fashion with his detective flatmate. And rightly or wrongly, that mood will spill over into his judgment. It’s called the affect heuristic: how we feel is how we think. A happy and relaxed state makes for a more accepting and less guarded worldview. Before Watson even knows that someone is soon to arrive, he is already set to like the visitor.

  And once the visitor enters? It’s just like that party. When we see a stranger, our mind experiences a predictable pattern of activation, which has been predetermined by our past experiences and our current goals—which includes our motivation—and state of being. When Miss Mary Morstan enters 221B Baker Street, Watson sees, “a blonde young lady, small, dainty, well gloved, and dressed in the most perfect taste. There was, however, a plainness and simplicity about her costume which bore with it a suggestion of limited means.” Right away, the image stirs up memories in his head of other young, dainty blondes Watson has known—but not frivolous ones, mind you; ones who are plain and simple and undemanding, who do not throw their beauty in your face but smooth it over with a dress that is somber beige, “untrimmed and unbraided.” And so, Mary’s expression becomes “sweet and amiable, her large blue eyes were singularly spiritual and sympathetic.” Watson concludes his opening paean with the words, “In an experience of women which extends over many nations and three separate continents, I have never looked upon a face which gave a clearer promise of a refined and sensitive nature.”

  Right away, the good doctor has jumped from a color of hair and complexion and a style of dress to a far more reaching character judgment. Mary’s appearance suggests simplicity; perhaps so. But sweetness? Amiability? Spirituality? Sympathy? Refinement and sensitivity? Watson has no basis whatsoever for any of these judgments. Mary has yet to say a single word in his presence. All she has done is enter the room. But already a host of biases are at play, vying with one another to create a complete picture of this stranger.

  In one moment, Watson has called on his reputedly vast experience, on the immense stores of his attic that are labeled WOMEN I’VE KNOWN, to flesh out his new acquaintance. While his knowledge of women may indeed span three separate continents, we have no reason to believe that his assessment here is accurate—unless, of course, we are told that in the past, Watson has always judged a woman’s character successfully from first glance. And somehow I doubt that’s the case. Watson is conveniently forgetting how long it took to get to know his past companions—assuming he ever got to know them at all. (Consider also that Watson is a bachelor, just returned from war, wounded, and largely friendless. What would his chronic motivational state likely be? Now, imagine he’d been instead married, successful, the toast of the town. Replay his evaluation of Mary accordingly.)

  This tendency is a common and powerful one, known as the availability heuristic: we use what is available to the mind at any given point in time. And the easier it is to recall, the more confident we are in its applicability and truth. In one of the classic demonstrations of the effect, individuals who had read unfamiliar names in the context of a passage later judged those names as famous—based simply on the ease with which they could recall them—and were subsequently more confident in the accuracy of their judgments. To them, the ease of familiarity was proof enough. They didn’t stop to think that availability based on earlier exposure could possibly be the culprit for their feelings of effortlessness.

  Over and over, experimenters have demonstrated that when something in the environment, be it an image or a person or a word, serves as a prime, individuals are better able to access related concepts—in other words, those concepts have become more available—and they are more likely to use those concepts as confident answers, whether or not they are accurate. Mary’s looks have triggered a memory cascade of associations in Watson’s brain, which in turn creates a mental picture of Mary that is composed of whatever associations she happened to have activated but does not necessarily resemble the “real Mary.” The closer Mary fits with the images that have been called up—the representativeness heuristic—the stronger the impression will be, and the more confident Watson will be in his objectivity.

  Forget everything else that Watson may or may not know. Additional information is not welcome. Here’s one question the gallant doctor isn’t likely to ask himself: how many actual women does he meet who end up being refined, sensitive, spiritual, sympathetic, sweet, and amiable, all at once? How typical is this type of person if you consider the population at large? Not very, I venture to guess—even if we factor in the blond hair and blue eyes, which are doubtless signs of saintliness and all. And how many women in total is he calling to mind when he sees
Mary? One? Two? One hundred? What is the total sample size? Again, I’m willing to bet it is not very large—and the sample that has been selected is inherently a biased one.

  While we don’t know what precise associations are triggered in the doctor’s head when he first sees Miss Morstan, my bet would be on the most recent ones (the recency effect), the most salient ones (the ones that are most colorful and memorable; all of those blue-eyed blondes who ended up being uninteresting, drab, and unimpressive? I doubt he is now remembering them; they may as well have never existed), and the most familiar ones (the ones that his mind has returned to most often—again, likely not the most representative of the lot). And those have biased his view of Mary from the onset. Chances are, from this point forward, it will take an earthquake, and perhaps even more than that, to shake Watson from his initial assessment.

  His steadfastness will be all the stronger because of the physical nature of the initial trigger: faces are perhaps the most powerful cue we have—and the most likely to prompt associations and actions that just won’t go away.

  To see the power of the face in action, look at these pictures.

  1. Which face is the more attractive? and 2. Which person is the more competent?

  If I were to flash these pictures at you for as little as one-tenth of a second, your opinion would already most likely agree with the judgments of hundreds of others to whom I’ve shown pictures of these two individuals in the same way. But that’s not all: those faces you just looked at aren’t random. They are the faces of two rival political candidates, who ran in the 2004 U.S. senate election in Wisconsin. And the rating you gave for competence (an index of both strength and trustworthiness) will be highly predictive of the actual winner (it’s the man on the left; did your competence evaluation match up?). In approximately 70 percent of cases, competence ratings given in under a second of exposure will predict the actual results of political races. And that predictability will hold in elections that range from the United States to England, from Finland to Mexico, and from Germany to Australia. From the strength of a chin and the trace of a smile, our brains decide who will serve us best. (And look at the result: Warren G. Harding, the most perfect square-jawed president that ever was.) We are wired to do just what we shouldn’t: jump to conclusions based on some subtle, subconscious cue that we’re not even aware of—and the repercussions extend to situations far more serious than Watson’s trusting too much in a client’s pretty face. Unprepared, he never stands a chance at that “true cold reason” that Holmes seems to hold in the tips of his fingers.