Farnam Street helps you make better decisions, innovate, and avoid stupidity.

With over 350,000 monthly readers and more than 87,000 subscribers to our popular weekly digest, we've become an online intellectual hub.

How to Think Like Sherlock Holmes

Baker Street

“Choice of attention – to pay attention to this and ignore that – is to the inner life what choice of action is to the outer. In both cases, a man is responsible for his choice and must accept the consequences, whatever they may be.”
— W. H. Auden

***

When it comes to using our minds, we all want to learn how to think like SherLock Holmes.

mastermind - how to think like sherlock holmes

Maria Konnikova’s book, Mastermind: How To Think Like Sherlock Holmes, takes a deep look at Sherlock Holmes’s methodology to develop the habits of mind that will allow us to mindfully engage the world.

Holmes has a step up on most people. “For most of his life, he had been honing a method of mindful interaction with the world.” To him, this was a skill that came naturally. “What Sherlock Holmes offers isn’t just a way of solving a crime. It is an entire way of thinking. … It is an approach born out of the scientific method that transcends science and crime both and can serve as a model for thinking, a way of being, even, just as powerful in our time as it was in Conan Doyle’s.”

The idea of mindfulness itself is by no means a new one. As early as the end of the nineteenth century, William James, the father of modern psychology, wrote that, ‘The faculty of voluntarily bringing back a wandering attention, over and over again, is the very root of judgment, character, and will. … An education which should improve this faculty would be the education par excellence.’ That faculty, at its core, is the very essence of mindfulness. And the education that James proposes, an education in a mindful approach to life and to thought.

Ellen Langer, in the 1970s demonstrated that mindfulness could even improve “judgment, character, and will.”

In recent years, studies have shown that meditation-like thought (an exercise in the very attentional control that forms the center of mindfulness), for as little as fifteen minutes a day, can shift frontal brain activity toward a pattern that has been associated with more positive and more approach-oriented emotional states, and that looking at scenes of nature, for even a short while, can help us become more insightful, more creative, and more productive. We also know, more definitively than we ever have, that our brains are not built for multitasking — something that precludes mindfulness altogether. When we are forced to do multiple things at once, not only do we perform worse on all of them but our memory decreases and our general wellbeing suffers a palpable hit.

But for Sherlock Holmes, mindful presence is just a first step. It’s a means to a far larger, far more practical and practically gratifying goal. Holmes provides precisely what William James had prescribed: an education in improving our faculty of mindful thought and in using it in order to accomplish more, think better, and decide more optimally. In its broadest application, it is a means for improving overall decision making and judgment ability, starting from the most basic building block of your own mind.

Never mistake mindlessness for mindfulness. “We have to move from passive absorption to active awareness. We have to engage.”

Engagement

As children, we are remarkably aware. We absorb and process information at a speed that we’ll never again come close to achieving. New sights, new sounds, new smells, new people, new emotions, new experiences: we are learning about our world and its possibilities. Everything is new, everything is exciting, everything engenders curiosity. And because of the inherent newness of our surroundings, we are exquisitely alert; we are absorbed; we take it all in. Who knows when it might come in handy?

But as we grow older, the blasé factor increases exponentially. Been there, done that, don’t need to pay attention to this, and when in the world will I ever need to know or use that. Before we know it, we have shed that innate attentiveness, engagement, and curiosity for a host of passive, mindless habits. And even when we want to engage, we no longer have that childhood luxury. Gone are the days where our main job was to learn, to absorb, to interact; we now have other, more pressing (or so we think) responsibilities to attend to and demands on our minds to address. And as the demands on our attention increase—an all too real concern as the pressures of multitasking grow in the increasingly 24/7 digital age—so, too, does our actual attention decrease. As it does so, we become less and less able to know or notice our own thought habits, and more and more allow our minds to dictate our judgments and decisions, instead of the other way around.

Pitfalls of the Untrained Brain

One of the things that characterizes Holmes’s thinking —and the scientific ideal—is a natural skepticism and inquisitiveness toward the world. Nothing is taken at face value.

It’s awfully easy to get tripped up. In fact, not only do we believe everything we hear, at least initially, but even when we have been told explicitly that a statement is false before we hear it, we are likely to treat it as true. For instance, in something known as the correspondence bias (a concept we’ll revisit in greater detail), we assume that what a person says is what that person actually believes—and we hold on to that assumption even if we’ve been told explicitly that it isn’t so; we’re even likely to judge the speaker in its light.

Daniel Kahneman believes there are two systems for organizing and filtering knowledge: system one and system two. System one is real-time. Think about the way we recognize speech or make an intuitive decision. This system makes judgments and decisions before our mental apparatus can consciously catch up. System two, on the other hand, is a slow process of thinking based on critical examination of evidence. Konnikova refers to these as System Watson and System Holmes.

In essence it comes down to one simple formula: to move from a System Watson- to a System Holmes-governed thinking takes mindfulness plus motivation. (That, and a lot of practice.) Mindfulness, in the sense of constant presence of mind, the attentiveness and hereness that is so essential for real, active observation of the world. Motivation, in the sense of active engagement.

“Powers of observation can be developed by cultivating the habit of watching things with an active, enquiring mind. It is no exaggeration to say that well developed habits of observation are more important in research than large accumulations of academic learning.” — W. I. B. Beveridge in The Art of Scientific Investigation

And of course applying these skills is incredibly difficult, when our brains want to default into quick, intuitive, thinking.

It is most difficult to apply Holmes’s logic in those moments that matter the most. And so, all we can do is practice, until our habits are such that even the most severe stressors will bring out the very thought patterns that we’ve worked so hard to master.

Of course what you allow into your brain is the starting point for how we think. And whether we think intuitively (system one) or more rationally (system two) what’s in our head affects our decisions.

Respect the attic
As Holmes tells Watson, “I consider that a man’s brain originally is like a little empty attic, and you have to stock it with such furniture as you choose.”

When I first heard the term brain attic, all I could picture in my seven-year-old head was the cover of the black-and-white Shel Silverstein book that sat prominently on my bookshelf, with its half-smiling, lopsided face whose forehead was distended to a wrinkled triangle, complete with roof, chimney, and window with open shutters. Behind the shutters, a tiny face peeking out at the world. Is this what Holmes meant? A small room with sloped sides and a foreign creature with a funny face waiting to pull the cord and turn the light off or on?

As it turns out, I wasn’t far from wrong. For Sherlock Holmes, a person’s brain attic really is an incredibly concrete, physical space. Maybe it has a chimney. Maybe it doesn’t. But whatever it looks like, it is a space in your head, specially fashioned for storing the most disparate of objects. And yes, there is certainly a cord that you can pull to turn the light on or off at will. As Holmes explains to Watson, “A fool takes in all the lumber of every sort that he comes across, so that the knowledge which might be useful to him gets crowded out, or at best is jumbled up with a lot of other things, so that he has a difficulty in laying his hands upon it. Now the skillful workman is very careful indeed as to what he takes into his brain-attic.”

That comparison, as it turns out, is remarkably accurate. Subsequent research on memory formation, retention, and retrieval has proven itself to be highly amenable to the attic analogy.

Attics have two components: structure and contents.

This sounds a lot like Charlie Munger’s view of elementary, worldly wisdom: storing key ideas on a latticework of mental models.

Well, the first rule is that you can’t really know anything if you just remember isolated facts and try and bang ‘em back. If the facts don’t hang together on a latticework of theory, you don’t have them in a usable form.

You’ve got to have models in your head. And you’ve got to array your experience both vicarious and direct on this latticework of models. You may have noticed students who just try to remember and pound back what is remembered. Well, they fail in school and in life. You’ve got to hang experience on a latticework of models in your head.

What are the models? Well, the first rule is that you’ve got to have multiple models because if you just have one or two that you’re using, the nature of human psychology is such that you’ll torture reality so that it fits your models, or at least you’ll think it does…

It’s like the old saying, ”To the man with only a hammer, every problem looks like a nail.” And of course, that’s the way the chiropractor goes about practicing medicine. But that’s a perfectly disastrous way to think and a perfectly disastrous way to operate in the world. So you’ve got to have multiple models.

And the models have to come from multiple disciplines because all the wisdom of the world is not to be found in one little academic department. That’s why poetry professors, by and large, are so unwise in a worldly sense. They don’t have enough models in their heads. So you’ve got to have models across a fair array of disciplines.

You may say, “My God, this is already getting way too tough.” But, fortunately, it isn’t that tough because 80 or 90 important models will carry about 90% of the freight in making you a worldly wise person. And, of those, only a mere handful really carry very heavy freight.

Konnikova carries the systems (Watson and Holmes) into how we remember.

Our default System Watson attic is jumbled and largely mindless. Gregson may have once known about Van Jansen but has lacked the requisite motivation and presence to retain his knowledge. Why should he care about old cases? Holmes, however, makes a conscious, motivated choice to remember cases past; one never knows when they might come in handy. In his attic, knowledge does not get lost. He has made a deliberate decision that these details matter. And that decision has, in turn, affected how and what – and when – he remembers.

Cultivating knowledge

To cultivate our knowledge actively, we need to realize that items are being pushed into our attic space at every opportunity. In our default state, we don’t often pay attention to them unless some aspect draws our attention—but that doesn’t mean they haven’t found their way into our attic all the same. They sneak in if we’re not careful, if we just passively take in information and don’t make a conscious effort to control our attention—especially if they are things that somehow pique our attention naturally: topics of general interest; things we can’t help but notice; things that raise some emotion in us; or things that capture us by some aspect of novelty or note.

It is all too easy to let the world come unfiltered into your attic space, populating it with whatever inputs may come its way or whatever naturally captures your attention by virtue of its interest or immediate relevance to you. When we’re in our default System Watson mode, we don’t “choose” which memories to store. They just kind of store themselves—or they don’t, as the case may be.

Observation
Before we include something into our brain attic we must first observe it. Konnikova writes:

Observation with a capital O — the way Holmes uses the word when he gives his new companion a brief history of his life with a single glance — does entail more than, well, observation (the lowercase kind). It’s not just about the passive process of letting objects enter into your visual field. It is about knowing what and how to observe and directing your attention accordingly: what details do you focus on? What details do you omit? And how do you take in and capture those details that you do choose to zoom in on? In other words, how do you maximize your brain attic’s potential? You don’t just throw any old detail up there, if you remember Holmes’s early admonitions; you want to keep it as clean as possible. Everything we choose to notice has the potential to become a future furnishing of our attics — and what’s more, its addition will mean a change in the attic’s landscape that will affect, in turn, each future addition. So we have to choose wisely.

Choosing wisely means being selective. It means not only looking but looking properly, looking with real thought. It means looking with the full knowledge that what you note — and how you note it — will form the basis of any future deductions you might make. It’s about seeing the full picture, noting the details that matter, and understanding how to contextualize those details within a broader framework of thought.

In his book, The Art of Scientific Investigation, W. I. B. Beveridge writes:

Training in observation follows the same principles as training in any activity. At first one must do things consciously and laboriously, but with practice the activities gradually become automatic and unconscious and a habit is established. Effective scientific observation also requires a good background, for only by being familiar with the usual can we notice something as being unusual or unexplained.

Paying Attention Is Anything but Elementary

Attention is a limited resource. Paying attention to one thing necessarily comes at the expense of another. Letting your eyes get too taken in by all of the scientific equipment in the laboratory prevents you from noticing anything of significance about the man in that same room. We cannot allocate our attention to multiple things at once and expect it to function at the same level as it would were we to focus on just one activity. Two tasks cannot possibly be in the attentional foreground at the same time. One will inevitably end up being the focus, and the other — or others — more akin to irrelevant noise, something to be filtered out. Or worse still, none will have the focus and all will be, albeit slightly clearer, noise, but degrees of noise all the same.

Attentional blindness, paying attention to one thing at the expense of another, is often how pickpocketing works. Yet all is not lost.

The Holmes solution? Habit.

The Holmes solution? Habit, habit, habit. That, and motivation. Become an expert of sorts at those types of decisions or observation that you want to excel at making. … If you learn first how to be selective accurately, in order to accomplish precisely what it is you want to accomplish, you will be able to limit the damage that System Watson can do by preemptively teaching it to not muck it up. The important thing is the proper, selective training — the presence of mind — coupled with the desire the motivation to master your thought process.

No one says it’s easy. When it comes right down to it, there is no such thing as free attention; it all has to come from somewhere. And every time we place an additional demand on our attentional resources — be it by listening to music while walking, checking our email while working, or following five media streams at once — we limit the awareness that surrounds any one aspect and our ability to deal with it in an engaged, mindful, and productive manner.

Take a Step Back
To think we also need distance.

One of the most important ways to facilitate imaginative thinking is through distance. In ‘The Adventure of the Bruce-Partington Plans,’ a case that comes quite late in the Holmes-Watson partnership, Watson observes:

One of the most remarkable characteristics of Sherlock Holmes was his power of throwing his brain out of action and switching all his thoughts on to lighter things whenever he had convinced himself that he could no longer work to advantage. I remember that during the whole of that memorable day he lost himself in a monograph which he had undertaken upon the Polyphonic Motets of Lassus. For my own part I had none of this power of detachment, and the day, in consequence appeared to be interminable.

Forcing your mind to take a step back is a tough thing to do. It seems counterintuitive to walk away from a problem that you want to solve. But in reality, the characteristic is not so remarkable either for Holmes or for individuals who are deep thinkers. The fact that it is remarkable for Watson (and that he self-admittedly lacks the skill) goes a long way to explaining why he so often fails when Holmes succeeds.

Not only does distance facilitate imaginative thinking but it also helps counter short-term emotions.

A final thought on Mindfulness comes from Sam McNerney. Referencing a recently published paper by Erika Carlson, a PhD candidate at Washington University, he writes:

Carlson proposes that mindfulness, defined as “paying attention to one’s current experience in a nonevaluative way,” may provide an effective means for acquiring self-knowledge. The “mindful” individual, as opposed to his introspective peer, does not analyze or interpret nor does he ask questions that lend themselves to intricate narratives that confirm his intuitions. As Carlson puts it, “[mindfulness] involves noticing thoughts and emotions as they arise without elaboration or rumination. This kind of detached observation… allows people to experience fairly aversive thoughts and emotions as temporary events rather than experiences that require a response or an explanation.”

How can we achieve mindfulness? Carlson mentions two strategies that both stress observation over questioning and introspection. The first is nonevalution observation, which encourages people to consider information even if it threatens the ego. Carlson cites a study that primed participants with morbid thoughts about their death. The researchers noted that the typical response to “mortality salience” is to hunker down, bolster self-esteem, and defend your worldview. However, individuals who scored higher on tests of mindfulness “defended their worldviews less, thought about death longer, and suppressed negative thoughts about death less.” An observant ego, in sum, is a healthy ego.

Second, we should pay attention to all the available information in a given moment (i.e., all thoughts, feelings, and behaviors). If this sounds obvious consider that compared to untrained individuals, people with mindfulness training preform better on conflict monitoring tasks, orientation tasks, standardized tests and working memory tasks.* Like impartial spectators, they consider all of the facts and avoid jumping to conclusions.

Mastermind: How to Think Like Sherlock Holmes was a great read.

Editor’s note: Follow your curiosity to The Art of Observation.