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Lessons from Sherlock Holmes: The Power of Public Opinion

I’d like to continue today with the tale of the “Copper Beeches” that we left off last time. The exchange between Holmes and Watson on the nature of country houses does not end with the initial dialogue.

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


I’d like to continue today with the tale of the “Copper Beeches” that we left off last time. The exchange between Holmes and Watson on the nature of country houses does not end with the initial dialogue. Instead, it moves forward in as interesting a philosophical vein as it was begun. Except, from individual perception and the subjectivity of experience, the two friends progress to a wider social commentary: what is it that makes society function as it does? Where Rousseau and Hobbes went before him, Holmes bravely ventures forth. Surely, he has taken up with more formidable foes in the past.

Recall that Holmes has just told Watson that the very houses his friend finds so charming are to him bastions of crime. Watson responds:

“Good heavens!” I cried. “Who would associate crime with these dear old homesteads?”

“They always fill me with a certain horror. It is my belief, Watson founded upon my experience, that the lowest and vilest alleys in London do not present a more dreadful record of sin than does the smiling and beautiful countryside.”

“You horrify me!”

“But the reason is very obvious. The pressure of public opinion can do in the town what the law cannot accomplish. There is no lane so vile that the scream of a tortured child, or the thud of a drunkard’s blow, does not beget sympathy and indignation among the neighbours, and then the whole machinery of justice is ever so close that a word of complaint can set it going, and there is but a step between the crime and the dock. But look at those lonely houses, each in its own fields, filled for the most part with poor ignorant folk who know little of the law. Think of the deeds of hellish cruelty, the hidden wickedness which may go on, year in, year out, in such places, and none the wiser.”


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Here, Holmes hits upon several threads that form some of the backbone of social psychology: we tend to behave quite differently when we expect to be observed than when we don’t and we are acutely responsive to prevailing social mores and social norms.

The actual or future presence of others affects our behavior

When we decide to do something, should it matter to us whether or not someone else is watching? While theoretically, it’s easy to argue that it shouldn’t, that the same behavioral norms apply no matter what, in practice, it usually does. This goes for minor behaviors (Will you pick your nose in public? What about if you’re pretty sure no one is watching you?) as well as much more important ones (Will you hurt someone, be it physically or otherwise, if others are observing your interaction? What about if you’re fairly certain the misdeed will never go beyond the two of you?).

Many studies have shown that the answers to those questions differ significantly. For instance, people are much more likely to cheat (on an exam, on taxes, on each other) if they don’t think they’ll be caught. They are more likely to steal in a corporate environment that fosters a feeling of anonymity than in a more personal setting. They are more likely to be unfair in games like dictator (where they decide how much of a certain sum of money they will keep and how much they will give to another person) or ultimatum (the same as dictator, except if the other person rejects the division, neither player receives anything) and much more likely to betray their partner in a prisoner’s dilemma if they think they are anonymous and have no wider audience than if they and their partner have a name and face or are observed by others. And on the flipside, individuals tend to be much more generous and altruistic when someone else is looking. In game settings, divisions become much more fair, cooperation more common than any theory of simple value-optimizing behavior would predict. In the real world, philanthropic donations rise and helping and law-abiding behaviors increase.

People, social psychological theory predicts, are neither always the noble savage nor engaged in a perpetual war of all against all. Instead, various facets of character come out depending on the social qualities of a situation. Of course, these are generalizations. There are always those individuals who will behave the same–be it for better or worse–circumstances notwithstanding. But in general, the principle holds true.

Consider, from Holmes’s own realm of crime, the case of Kitty Genovese, a 28-year-old woman who was savagely murdered on a street outside her apartment building. 38 people watched. Not a single one called the police or acted to stop the slowly unfolding murder. Why? Part of the explanation, surely, is in the diffusion of responsibility (why should I be the one to do something when someone else easily can?), which is the opposite of the social effects predicted by a strong influence of social norms. And yet, on closer inspection, it is not so unrelated: in the dark, behind the cover of windows, people become anonymous. They are not being observed by others. They know they are not being observed by others. And they are isolated in multiple ways–walls, darkness, fear. I would venture to guess that the criminal was counting on the dark, the isolation, and the anonymity to counteract the effects of social cohesion. I wonder: would someone have stepped in to help if the circumstances had shifted just a little bit? If the murder had moved up a few hours, into the daylight? If someone had passed by outside, no longer covered by curtains but in full view? If at least one person stepped forward to shatter the illusion of unaccountability?

I remember an anecdote that my dad likes to tell, about a dinner party. There is a basket of delicious, steaming rolls right out of the oven in the middle of the table. The guests all help themselves. They take seconds. And then, alas: there is only one roll left. Everyone eyes it with thinly-veiled yearning but no one quite dares to be the first to take it or to inquire as to its fate. Suddenly, the lights go out. The house has lost electricity. In the dark, there’s a piercing scream.

It sounds like a set-up to an Agatha Christie mystery. But the solution is a simple one: the scream came from the hostess, who covered the roll with her hand at the same moment as each guest went to grab it with his fork.

Not quite Holmes’s level of crime, but the point gets across. The dark is a wondrously freeing thing.

Prevailing societal norms make a difference

Consider also the importance of what exactly the prevailing social norms are. If a society were to openly countenance violence, Holmes’s vision of safe alleys would vanish.

This principle (albeit in a non-violent context) is illustrated in a clever manipulation of social feedback by a group of researchers interested in energy conservation. A California energy company allowed the experimenters to add a few details to the regular monthly bill. Now, people not only saw their own energy usage, but the usage of those around them (and not just anyone; they saw details for households that had been deemed comparable to their own). In other words, they were given information on the social norms of usage for energy, given their own circumstances. What happened? Those that used too much energy brought their usage down – but those who were under average actually increased consumption, creating a so-called boomerang effect. Norms, it seems, could act in both positive and negative ways. The important detail wasn’t in the precise action to take, but simply in what to do to be in line with the average behavior.

However, the study did not end there. There was one more step. Now, in addition to usage information, people received an emoticon on their bills: a smiling face if their usage was below average, and a frowning face if their usage was above average. Suddenly, the boomerang effect disappeared. Everyone wanted a smiley face.

What was going on? The researchers had captured what Holmes had predicted: not only social norms of behavior (to commit a crime or not, to expend additional household energy or not) but social approval (or in Holmes’s words, “the pressure of public opinion”) matter when we decide on our actions. Indeed, time and time again, studies have shown that praise, both verbal and in non-monetizable forms like stickers, can be a much more effective motivator of behavior than tangible monetary rewards.

Behavior is not stable. Circumstances matter.

In his evaluation of the interaction between person, society, norms, social pressure, and eventual behavior, Holmes is much more perceptive and less idealistic here than many of his contemporaries (and his successors). He doesn’t glamorize human behavior or human society. He doesn’t idealize or romanticize human tendencies. Instead, he gets at the heart of why laws so often work as they do, what it is that holds society together–that social glue of human behavior.

We don’t act in a vacuum. Each action comes with thoughts of consequences and contingencies. The question, it ends up, is not so much whether a tree will make a sound if it falls in the forest with no one to hear it, but if a single person observing that tree fall will try to move it out of the way if it lands across a road, even with no one to observe him and no one who will ever know of his good deed.

Photo credit: From “The Adventure of the Copper Beeches.” By Sidney Paget (1860 – 1908) (File published on Camden House (Ignisart.com)) [Public domain], via Wikimedia Commons.

Previously in this series:

Don’t Just See, Observe: What Sherlock Holmes Can Teach Us About Mindful Decisions Lessons from Sherlock Holmes: Paying Attention to What Isn’t There Lessons from Sherlock Holmes: Cultivate What You Know to Optimize How You Decide Lessons from Sherlock Holmes: Perspective Is Everything, Details Alone Are Nothing Lessons from Sherlock Holmes: Don’t Underestimate the Importance of Imagination Lessons from Sherlock Holmes: Confidence Is good; Overconfidence, Not So Much Lessons from Sherlock Holmes: The Situation Is in the Mindset of the Observer

Maria Konnikova is a science journalist and professional poker player. She is author of the best-selling books The Biggest Bluff (Penguin Press, 2020), The Confidence Game (Viking Press, 2016) and Mastermind: How to Think Like Sherlock Holmes (Viking Press, 2013).

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