A Study in Scarlet


Sir Arthur Conan Doyle

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Observation and Deduction Theme Analysis

Themes and Colors
Observation and Deduction Theme Icon
Injustice and Hypocrisy Theme Icon
Gender and Misogyny Theme Icon
Revenge and Murder Theme Icon
LitCharts assigns a color and icon to each theme in A Study in Scarlet, which you can use to track the themes throughout the work.
Observation and Deduction Theme Icon

Observation and deduction are the lifeblood of A Study in Scarlet, especially in terms of the novel’s format and characterization of Sherlock Holmes. Much of the novel (all but five chapters out of fourteen) is presented as “reminiscences” from John Watson’s journal, a record of his observations of both the case and Holmes. The first interaction between Watson and the consulting detective represents the essence of the Holmes-Watson dynamic throughout the story: Holmes is attentive to clues to which others are oblivious, allowing him to quickly deduce information (in this case, Watson’s recent return from Afghanistan), and Watson is astonished by Holmes’ abilities.

The narrator devotes an entire chapter to “The Science of Deduction,” in which Watson makes his own observations of Holmes, attempting to determine the nature of his roommate’s occupation based on the strengths and weaknesses in Holmes’ knowledge. However, Watson finds himself unable to deduce what Holmes does for a living. By contrast, in his article “The Book of Life,” Holmes claims that he can ascertain another person’s history simply with careful observation (hence his deduction that Watson was an army doctor in Afghanistan).

Holmes’ observational and deduction skills are crucial to his characterization, as these skills originally belonged to the real-life person who inspired Doyle’s creation of Holmes: Joseph Bell. Doyle’s former mentor, Bell was a surgeon with keen deductive reasoning skills. Like Holmes, he often made deductions about people based on his observations of minute details. While Watson’s purpose in the novel is mainly to admire Holmes’ skills (and thus Joseph Bell’s skills), he also serves as a foil to Holmes. Unlike Watson, who makes observations about Holmes but cannot analyze them, Holmes skillfully employs both observation and analysis in his detective work. However, it is not merely the analytical skills that distinguish a great detective but also the ability to use them carefully. For example, though Lestrade spots the word “rache” at the crime scene first, he incorrectly jumps to the wrong conclusion that the writer had meant to write “Rachel.” Holmes, on the other hand, observes the exaggerated German styling of the lettering and deduces that the murderer had written the German word for “revenge” in order to throw the police off his trail.

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Observation and Deduction ThemeTracker

The ThemeTracker below shows where, and to what degree, the theme of Observation and Deduction appears in each chapter of A Study in Scarlet. Click or tap on any chapter to read its Summary & Analysis.
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Observation and Deduction Quotes in A Study in Scarlet

Below you will find the important quotes in A Study in Scarlet related to the theme of Observation and Deduction.
Part 1, Chapter 1 Quotes

Holmes is a little too scientific for my tastes — it approaches to cold-bloodedness. I could imagine his giving a friend a little pinch of the latest vegetable alkaloid, not out of malevolence, you understand, but simply out of a spirit of inquiry in order to have an accurate idea of the effects. To do him justice, I think that he would take it himself with the same readiness. He appears to have a passion for definite and exact knowledge….Yes, but it may be pushed to excess. When it comes to beating the subjects in the dissecting-rooms with a stick, it is certainly taking rather a bizarre shape.

Related Characters: Stamford (speaker), Sherlock Holmes, John H. Watson
Page Number: 10
Explanation and Analysis:

Let me see — what are my other shortcomings. I get in the dumps at times, and don’t open my mouth for days on end. You must not think I am sulky when I do that. Just let me alone, and I’ll soon be right. What have you to confess now? It’s just as well for two fellows to know the worst of one another before they begin to live together.

Related Characters: Sherlock Holmes (speaker), John H. Watson
Page Number: 13
Explanation and Analysis:
Part 1, Chapter 2 Quotes

Nothing could exceed his energy when the working fit was upon him; but now and again a reaction would seize him, and for days on end he would lie upon the sofa in the sitting-room, hardly uttering a word or moving… I have noticed such a dreamy, vacant expression in his eyes, that I might have suspected him of being addicted to the use of some narcotic, had not the temperance and cleanliness of his whole life forbidden such a notion.

Related Characters: John H. Watson (speaker), Sherlock Holmes
Page Number: 15
Explanation and Analysis:

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. 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 skilful workman is very careful indeed as to what he takes into his brain-attic. He will have nothing but the tools which may help him in doing his work, but of these he has a large assortment, and all in the most perfect order… It is of the highest importance, therefore, not to have useless facts elbowing out the useful ones.

Related Characters: Sherlock Holmes (speaker), John H. Watson
Page Number: 17
Explanation and Analysis:

Its somewhat ambitious title was “The Book of Life”, and it attempted to show how much an observant man might learn by an accurate and systematic examination of all that came in his way. It struck me as being a remarkable mixture of shrewdness and of absurdity. The reasoning was close and intense, but the deductions appeared to me to be far-fetched and exaggerated. The writer claimed by a momentary expression, a twitch of a muscle or a glance of an eye, to fathom a man’s inmost thoughts. Deceit, according to him, was an impossibility in the case of one trained to observation and analysis. His conclusions were as infallible as so many propositions of Euclid. So startling would his results appear to the uninitiated that until they learned the processes by which he had arrived at them they might well consider him as a necromancer.

Related Characters: John H. Watson (speaker), Sherlock Holmes
Page Number: 19
Explanation and Analysis:

“There are no crimes and criminals in these days,” he said, querulously. “What is the use of having brains in our profession? I know well that I have it in me to make my name famous. No man lives or has ever lived who has brought the same amount of study and of natural talent to the detection of crime which I have done. And what is the result? There is no crime to detect, or, at most, some bungling villainy with a motive so transparent that even a Scotland Yard official can see through it.”

Related Characters: Sherlock Holmes (speaker), John H. Watson
Page Number: 23
Explanation and Analysis:
Part 1, Chapter 3 Quotes

“They say that genius is an infinite capacity for taking pains,” he remarked with a smile. “It’s a very bad definition, but it does apply to detective work.”

Related Characters: Sherlock Holmes (speaker), John H. Watson, Lestrade, Tobias Gregson
Page Number: 34
Explanation and Analysis:
Part 1, Chapter 4 Quotes

“I’m not going to tell you much more of the case, Doctor. You know a conjurer gets no credit once he has explained his trick; and if I show you too much of my method of working, you will come to the conclusion that I am a very ordinary individual after all.”

“I shall never do that,” I answered; “you have brought detection as near an exact science as it ever will be brought in this world.”

My companion flushed up with pleasure at my words, and the earnest way in which I uttered them. I had already observed that he was as sensitive to flattery on the score of his art as any girl could be of her beauty.
“I’ll tell you one other thing,” he said.

Related Characters: Sherlock Holmes (speaker), John H. Watson (speaker)
Page Number: 38
Explanation and Analysis: