Did Sherlock Holmes use the deductive method?

The literary hero Conan Doyle - the brilliant detective Sherlock Holmes - talks a lot about his method of deduction. And by this he often puzzles readers who are familiar with the elementary concepts of logic. After all, deductive thinking is an inference leading from the general to the particular. The simplest example of such a reasoning: we know about the force of gravity of the Earth; We have a general idea that water falls down, but does not rush up; Repeatedly observed the process of water fall. These general messages allow us to imagine logically how the Niagara Falls (private) looks, although we have never seen it.

But to all of us the famous Sherlock Holmes uses completely different kinds of inferences, rather, more known as induction, that is, the ascent from the particular to the general. In the dirt on the boots, the detective concludes that the man came from the countryside, according to the shoemaker's patches and cues, that the owner of the shoes is a poor man, and concludes by signing a railway ticket that he came to London by train. In the disclosure of crimes, the famous detective goes through a causal chain: the ashes from the cigar - the smoker - his motives - the personality of the smoker. And in the end he draws a conclusion: the criminal is Mr X. In the case of Holmes's notorious deduction, the reflections would go a very different way: Mr. X is very much like a criminal, while other people involved in this matter do not. His past is dark. He had a motive to kill the victim. At the time of the crime, he does not have an alibi. Therefore, the murderer is Mr. X.

So what deductive method does Holmes use in the process of disclosing the crime? At first, it seems that on the basis of the smallest details, he recreates the picture of the crime, as if it is being played out again before his eyes. For example, in the case of the loss of the treasure of Agra: on the trail of a small foot with protruding fingers, the detective guesses that the person who left the trail was short and never wore shoes. Another mental effort, and here's to you: the criminal is a pygmy from the Andaman Islands.

It would seem that here there is a pure induction - an ascent from the private to the general (from private evidence to the overall picture of the crime). Whereas the deductive method is a descent from the general to the particular. But in fact, there is no contradiction here. Holmes says: "Any life is an incessant causal chain, and we can study the nature of this chain only by its link". Remember the example of water and Niagara Falls? Here is another important quotation from Conan Doyle, where the literary hero says so about his method: "All crimes reveal a great generic similarity. They (the agents of Scotland Yard) introduce me to the circumstances of a case. Knowing the details of 1000 cases, it would be strange not to unravel the 1001th. "

Thus, Holmes's deductive method presupposes knowledge of the main crimes (for example, murder, theft, forgery). Murders from him are classified according to the "family tree" for murder from jealousy, for profit, for revenge, etc. Later it turns out that the murder for the inheritance of the duke and the murder committed for the possession of the Esquire estate also have their own specifics, and so on, down to the smallest detail. The detective, or rather, the author, being an Englishman and having an idea of the island (that is, accepted in the British Isles) case law, proceeds from the premise that a new, as yet undefined crime had precedent in the past, This form should be adjusted.

We can say with confidence that, despite external induction, Holmes uses deductive method in his logical calculations. Playing on a violin or smoking at the fireplace, the brilliant detective thinks: to what category is this or that crime to be attributed? Revenge? Jealousy? Thirst for profit? Sherlock throws all the unsuitable, like sifting wheat from the husks, until the only correct grain in his hands is left. And he himself about his method says: "I throw aside all the impossible, and what remains - and there is an answer to the question, no matter how fantastic it may seem."