No matter how crowded your life gets, it pays if you find time to read the Sherlock Holmes stories at least once a year.

Sherlock Holmes would have made a superb copywriterBut however often you read them, there’s plenty in these books that’s helpful for copywriters and anyone else who needs to know what makes people tick.

I was reminded of this earlier today when I was reading The Adventure of the Blue Carbuncle over my morning coffee.

Without giving too much of the plot away, the Countess of Morcar’s immensely valuable blue carbuncle ends up inside the entrails of a goose. The only question is which one?

Holmes narrows the trail down to a market stall in Covent Garden, where he asks where the stallholder got the geese he later supplied to the Alpha Inn.

To his surprise, the questions ignites a powder keg of resentment:

“When I pay good money for a good article there should be an end of the business; but it’s ‘Where are the geese?’ and ‘Who did you sell the geese to?’ and ‘What will you take for the geese?’ One would think they were the only geese in the world, to hear the fuss that is made over them.”

A lesser man than Holmes would have given up trying to locate the geese – or more likely, would have annoyed the stallholder even more by persisting with his original question.

But Holmes changes tack in a way that will be familiar to many good copywriters: he shuts up about his own needs and switches his attention to the stallholder’s interests instead.

You interest me strangely…

Holmes bets the stallholder a sovereign that the geese supplied to the Alpha Inn were country bred. The ruse works like a charm, and the stallholder reaches for his ledger.

“That’s the list of the folk from whom I buy. D’you see? Well, then, here on this page are the country folk, and the numbers after their names are where their accounts are in the big ledger. Now, then! You see this other page in red ink? Well, that is a list of my town suppliers. Now, look at that third name. Just read it out to me.”

“Mrs. Oakshott, 117, Brixton Road — 249,” read Holmes.

Bingo. Holmes has the information he needs. And best of all, he explains how he got it:

“When you see a man with whiskers of that cut and the ‘Pink ‘un’ protruding out of his pocket, you can always draw him by a bet,” said he. “I daresay that if I had put 100 pounds down in front of him, that man would not have given me such complete information as was drawn from him by the idea that he was doing me on a wager.”

From a copywriting point of view, the message is simple: find out what interests your audience, and use it to get the information you need. If you put your own interests first, you’ll hit a brick wall.

It’s a bit like those adverts for the Economist that get sales and subscriptions by flattering the reader’s self-belief that they’re extremely intelligent and well informed. Like this one:

While I’m not the target audience (I think breakfast bars when someone mentions Jordan), I can see how the flattery in this ad will make certain people buy the Economist.

But the psychology is nothing new – and it’s a technique the world’s most famous detective was using as early as 1890 in The Sign of the Four.

Flattery gets a detective everywhere

Holmes needs to get a description of a steam launch so he can track down a wooden-legged fugitive and a savage.

As he approaches the house of the owner, a boy of about six years old comes running out – chased by his mother.

“You come back and be washed, Jack,” she shouted. “Come back, you young imp; for if your father comes home and finds you like that he’ll let us hear of it.”

“Dear little chap!” said Holmes strategically. “What a rosy-cheeked young rascal! Now, Jack, is there anything you would like?”

The youth pondered for a moment.

“I’d like a shillin’,” said he.

“Nothing you would like better?”

“I’d like two shillin’ better,” the prodigy answered after some thought.

“Here you are, then! Catch! — A fine child, Mrs. Smith!”

There’s no quicker way to a mother’s heart than by kindness to her child. But Holmes is even cleverer.

Instead of pursuing a direct line of questioning, he lets the mother take the lead in the conversation.

“I am sorry, Mrs. Smith, for I wanted a steam launch, and I have heard good reports of the — Let me see, what is her name?”

“The Aurora, sir.”

“Ah! She’s not that old green launch with a yellow line, very broad in the beam?”

“No, indeed. She’s as trim a little thing as any on the river. She’s been fresh painted, black with two red streaks.”

“Thanks. I hope that you will hear soon from Mr. Smith. I am going down the river, and if I should see anything of the Aurora I shall let him know that you are uneasy. A black funnel, you say?”

“No, sir. Black with a white band.”

“Ah, of course. It was the sides which were black. Good-morning, Mrs. Smith. There is a boatman here with a wherry, Watson. We shall take it and cross the river.”

Once again, the super sleuth gets the information he needs. And once again he explains how he does it.

“The main thing with people of that sort,” said Holmes as we sat in the sheets of the wherry, “is never to let them think that their information can be of the slightest importance to you. If you do they will instantly shut up like an oyster. If you listen to them under protest, as it were, you are very likely to get what you want.”

You can see the same technique at work today in those amusing internet quizzes.

You know the sort of thing – “Which Girl Group Are You?” or “What Does Your Pet Say About You?”

And while your answers are little use to anyone, your contact details are. And if Sherlock Holmes were a copywriter today, he’d have the best subscriptions database on the planet.

I’d lay a sovereign on it.