Our most beloved heroes are talented detectives or lawyers. We all know authors such as Conan Doyle and Agatha Christie, who in their books created images of genius people using the famous deductive method. Perhaps, among all the grandiose detectives, such as Hercule Poirot, Miss Marple and others, Sherlock Holmes is a certain peak of a person who knows how to reason correctly and accurately, subtly observe and analyze facts.
The deductive way of thinking is widely used not only in popular works of literature and cinema, but also in our daily life.
It is imperative to be able to draw the right conclusions. To learn how to develop deduction, you first need to understand what it is and how it works.
What is deductive method and how does it work?
Deduction is a way of thinking in which the main conclusion is obtained from general reasoning to particular ones. Let us recall the situation that is described in the famous story about Sherlock Holmes "The Sign of the Four". The plot was as follows: a friend of Sherlock Holmes, Dr. Watson, decided to check what conclusions he can draw by observing fairly simple things. Watson gives Sherlock Holmes his watch and says: "What can you say by analyzing such an object as a watch?":
- seeing an antique watch engraved with the initials “G. W. ”, the detective realizes that they are family and, most likely, were acquired by Watson's father;
- at that time, watches were considered a precious thing and were inherited, according to the rules, to the eldest son. But Watson had a watch recently, although his father died many years ago. This means that Watson had an older brother;
- there are dents on the watch lid, therefore, the brother was sloppy (especially considering the importance of such a gift as a commemorative watch from a deceased father), etc.
As you can see, the famous detective was simply analyzing general facts and applying them to a particular situation, to Dr. Watson's watch. Interestingly, after the detective shared his conclusions with a friend, he was so shocked by the exact answer that he accused Sherlock of espionage. They say he found out everything in advance and is now taking advantage of the situation.
The reason for this reaction is quite simple. In his mind, Holmes did a fairly large analysis and made an equally huge logical conclusion. Therefore, knowing only the initial step of the inference (“What can you say when analyzing an object such as a watch?”) And the final result (which Holmes voiced to Watson), but at the same time not seeing each separate, intermediate step (the process of forming the conclusion: engraved initials - Watson's father, dents - sloppiness, etc.), the final conclusion can really be amazed.
To get the correct final result, it is necessary to justify each individual step of the inference so that, upon close examination, it can be seen that it was done correctly.
Ways to help you develop deduction
It is quite easy to develop deductive abilities no worse than that of any professional detective (fictional or real). Deduction is not something out of the ordinary, it is just a logical method. Therefore, for its development, it is necessary to keep the whole brain in good shape, and, therefore, not only logic, but also attention, memory, imagination. Learning to think quickly and compare facts will help you follow some tricks.
- Solve puzzles
Download or borrow any book from the library. It is important that these are not some difficult physical chemistry problems that you do not understand. Normal children's puzzles will do. Remember that being quick-witted requires knowledge in a variety of areas of life. Solving seemingly simple puzzles will teach you to think quickly, think outside the box and solve tasks.
Sherlock Holmes skillfully used not only the deduction method, but was also a very educated and intelligent person. And, therefore, in order to develop deduction as a famous detective, you also need to know and remember a lot. Incidentally, this is one example of inductive inference. To train your memory, learn the poems of your favorite poet, learn the main capitals of the countries of the world, the number pi ... Yes, everything that you have enough imagination for!
- Solve problems
If you are good at math, then start with simple arithmetic or geometry problems. Well-developed analytical skills will greatly facilitate the process of inference. Was biology your favorite subject at school? It doesn't matter either, there are a lot of simple biological tasks. The main thing is that you are interested, not too easy, but not too difficult. In addition, refreshing your school knowledge will never be superfluous, and a broad outlook is a faithful companion of deduction.
- Observe, study, analyze
To comprehend the method of deduction will help attention to detail, to every little thing. Try to always pay attention to things that seem insignificant. When communicating with friends, try to guess their emotions, mood. All people lie: someone just slightly embellishes reality, and someone is abusing trust. To learn to think like a detective, become a detective. Ask friends about the details, but not just like that, but really listen to them carefully. Compare facts you already know with new information. Just don't make everything paranoid!
- Expand your horizons
To use the deduction method correctly, you need to learn to draw conclusions. And this is not an easy task, especially when you know little. Try to read as many books, articles, magazines as possible. But remember, the outlook differs not in the number of books you read, but in the quality. If you thoughtlessly swallow information, it will be of little use. Read slowly and carefully, weighing every sentence, every reasoning or thought expressed by the author. A great way to broaden your horizons is to solve crosswords or scanwords.
- Watch the news
For example, you can choose a well-known politician or other media personality and completely follow her. What do they say about this person on one channel? And on the other? What information does he publish on his official blogs and social pages? Ask yourself what will happen next? What actions will be taken?
- Learn to think critically
Never take everything for granted. To develop the method of deduction, you must question every link in the logical chain. Your trump card is truth. If you draw deliberately false information in your conclusions, then no amount of deduction will help you. In today's world, where deception reigns all around, in order to get to the truth, you will have to put in a lot of effort. This method will keep your brain in constant tone, as well as develop ingenuity.
- Use induction as well as deduction
Induction is the opposite of deduction. Its essence is to come to a general conclusion from private conclusions. In order to master one instrument, one must fully master its opposite. Although calling induction and deduction as opposites would not be entirely correct. Rather, they are different parts that make up a single whole.
- Play PC games and watch TV shows
You heard right. Although, of course, some points are worth clarifying. Watch smart TV shows, documentaries, biographies of famous people. Play computer games that make you think: with a detective component, puzzles, quests. In addition, a lot of new, useful information can be gleaned from video games. By the way, there are a lot of games based on the works in which you are invited to try on the skin of the famous Holmes.
Why develop a deduction method?
Day after day, we have to deal with the proof of the truth of statements in a wide variety of situations. The deduction method is widely used in all spheres of our life and has great importance on the truth of certain judgments. Suppose you or someone you know has gotten into a bad story. An investigation is underway, there is some crime, the accused, detectives, lawyers, prosecutors, judges. One conclusion must be drawn: is the person guilty or innocent? To do this, one must be able to both justify the guilt of a person and prove his innocence.
The outcome, and, most importantly, the correctness of the final conclusion is of great importance for a person who finds himself in such a difficult situation. Therefore, it is extremely important, convincingly, convincingly and correctly from the available facts to build conclusions about his guilt or innocence. And this is just one example. There are many situations in which the truth of certain statements is important. That is why knowing and understanding how to develop deduction is useful to anyone.
Inductive reasoning
§ 1 Deduction and induction
“One drop of water ... a person who knows how to think logically can draw a conclusion about the existence of the Atlantic Ocean or Niagara Falls, even if he has not seen either one or the other and has never heard of them ... By the nails of a person, by his hands , shoes, the fold of trousers on the knees, by the thickening of the skin on the thumb and forefinger, by the expression on his face and the cuffs of his shirt - from such trifles it is easy to guess his profession. And there is no doubt that all this, taken together, will prompt a competent observer to the correct conclusions ",
This is a quote from a keynote article by the world's most famous consultant detective Sherlock Holmes. Based on the smallest details, he built logically flawless chains of reasoning and solved intricate crimes, often from the comfort of his apartment on Baker Street. Holmes used a deductive method that he himself created, which, as his friend Dr. Watson believed, put crime solving on the brink of an exact science.
Of course, Holmes somewhat exaggerated the importance of deduction in forensic science, but his reasoning about the deductive method did the trick. "Deduction" from a special and known only to a few term has become a commonly used and even fashionable concept. The popularization of the art of correct reasoning, and above all deductive reasoning, is no less a merit of Holmes than all the crimes he disclosed. He managed to "give logic the charm of a dream, making its way through the crystal labyrinth of possible deductions to the only shining conclusion" (V. Nabokov).
Definitions of deduction and induction
Deduction is a special case of inference.
In a broad sense, inference is a logical operation, as a result of which a new statement is obtained from one or several accepted statements (premises) - a conclusion (conclusion, consequence).
Depending on whether there is a connection of logical consequence between the premises and the conclusion, two types of inferences can be distinguished.
In deductive reasoning, this connection is based on a logical law, by virtue of which the conclusion with logical necessity follows from the accepted premises. A distinctive feature of such a conclusion is that it always leads from true premises to a true conclusion.
In inductive reasoning, the connection between premises and conclusions is based not on the law of logic, but on some factual or psychological foundations that do not have a purely formal character. In such a conclusion, the conclusion does not follow logically from the sprinkles and may contain information that is absent in them. The reliability of the premises does not mean, therefore, the reliability of the statement derived from them inductively. Induction provides only probable, or plausible, conclusions that need further verification.
For example, deductive conclusions include:
If it rains, the ground is wet.
It's raining.
The ground is wet.
If helium is metal, it is electrically conductive.
Helium is not electrically conductive.
Helium is not a metal.
The line separating premises from conclusion replaces the word "therefore."
Examples of induction are the following reasoning:
Argentina is a republic; Brazil is a republic;
Venezuela is a republic; Ecuador is a republic.
Argentina, Brazil, Venezuela, Ecuador are Latin American states.
All Latin American states are republics.
Italy is a republic; Portugal is a republic; Finland is a republic; France is a republic.
Italy, Portugal, Finland, France - Western European countries.
All Western European countries are republics.
Induction does not give a complete guarantee of obtaining a new truth from the existing ones. The maximum that can be talked about is a certain degree of probability of the statement being inferred. Thus, the premises of both the first and second inductive inference are true, but the conclusion of the first of them is true, and the second is false. Indeed, all Latin American states are republics; but among the Western European countries there are not only republics, but also monarchies, for example England, Belgium and Spain.
Especially characteristic deductions are logical transitions from general knowledge to a particular type:
All people are mortal.
All Greeks are human.
Therefore, all Greeks are mortal.
In all cases when it is required to consider some phenomena on the basis of an already known general rule and to draw the necessary conclusion regarding these phenomena, we reason in the form of deduction. Reasoning leading from knowledge about a part of objects (private knowledge) to knowledge about all objects of a certain class (general knowledge) are typical inductions. There is always the possibility that the generalization will be hasty and unfounded ("Napoleon is a commander; Suvorov is a commander; hence, every person is a commander").
At the same time, one cannot identify deduction with the transition from the general to the particular, and induction with the transition from the particular to the general. In the discourse “Shakespeare wrote sonnets; therefore, it is not true that Shakespeare did not write sonnets "there is deduction, but there is no transition from the general to the particular. The reasoning "If aluminum is plastic or clay is plastic, then aluminum is plastic" is, as it is commonly thought, inductive, but there is no transition from the particular to the general. Deduction is the derivation of conclusions that are as reliable as the accepted premises, induction is the derivation of probable (plausible) conclusions. Inductive inferences include both transitions from the particular to the general, and analogy, methods of establishing causal relationships, confirmation of consequences, purposeful justification, etc.
The particular interest in deductive reasoning is understandable. They allow one to obtain new truths from existing knowledge, and, moreover, with the help of pure reasoning, without resorting to experience, intuition, common sense, etc. Deduction provides a 100% guarantee of success, not just one or another - perhaps a high - probability of a true conclusion. Starting from true premises and reasoning deductively, we will definitely get reliable knowledge in all cases.
While emphasizing the importance of deduction in the process of developing and substantiating knowledge, one should not, however, separate it from induction and underestimate the latter. Almost all general provisions, including scientific laws, are the results of inductive generalization. In this sense, induction is the basis of our knowledge. By itself, it does not guarantee its truth and validity, but it generates assumptions, connects them with experience and thereby gives them a certain likelihood, a more or less high degree of probability. Experience is the source and foundation of human knowledge. Induction, starting from what is comprehended in experience, is a necessary means of its generalization and systematization.
All previously discussed reasoning schemes were examples of deductive reasoning. Propositional logic, modal logic, logical theory of categorical syllogism - all these are sections of deductive logic.
Conventional deductions
So, deduction is about making conclusions that are as valid as the assumptions you have accepted.
In ordinary reasoning, deduction only rarely appears in full and expanded form. Most often, we indicate not all used premises, but only some. General statements that can be assumed to be well known are usually omitted. Conclusions arising from the accepted premises are not always clearly formulated. The very logical connection that exists between the initial and the deduced statements is only sometimes marked by words like "therefore" and "means",
Often, deduction is so abbreviated that one can only guess about it. Restore it to full form, indicating all the necessary elements and their connections can be difficult.
“Thanks to an old habit,” Sherlock Holmes once remarked, “a chain of inferences arises in me so quickly that I came to a conclusion without even noticing the intermediate premises. However, they were, these parcels ",
Conducting deductive reasoning without omitting or shortening is quite cumbersome. A person who indicates all the premises of his conclusions creates the impression of a petty pedant. And at the same time, whenever there is doubt about the validity of the conclusion made, one should return to the very beginning of the reasoning and reproduce it in the fullest possible form. Without this, it is difficult or even impossible to detect the error that has been made.
Many literary critics believe that Sherlock Holmes was "written off" by A. Conan Doyle from Joseph Bell, professor of medicine at the University of Edinburgh. The latter was known as a talented scientist who possessed a rare observation and excellent command of the method of deduction. Among his students was the future creator of the image of the famous detective.
One day, says Conan Doyle in his autobiography, a patient came to the clinic and Bell asked him:
Have you served in the army?
Yes sir! - Standing at attention, the patient replied.
In the mountain rifle regiment?
That's right, Mr. Doctor!
Recently retired?
Yes sir!
Were you a sergeant?
Yes sir! - the patient answered dashingly.
Stood in Barbados?
That's right, Mr. Doctor!
The students who were present at this dialogue looked at the professor in amazement. Bell explained how simple and logical his conclusions were.
This man, having shown politeness and courtesy at the entrance to the office, still did not take off his hat. The army habit affected. If the patient had been in retirement for a long time, he would have learned civil manners long ago. In a posture, imperious, by nationality he is clearly Scottish, and this speaks for the fact that he was a commander. As for the stay in Barbados, the newcomer suffers from elephantism (elephantiasis) - such a disease is common among the inhabitants of those places.
Here deductive reasoning is grossly abbreviated. Omitted, in particular, all general statements, without which deduction would be impossible.
Sherlock Holmes became a very popular character, and there were even jokes about him and his creator.
For example, in Rome, Conan Doyle takes a cab, and he says: "Ah, Mr. Doyle, I greet you after your trip to Constantinople and Milan!" "How could you find out where I came from?" Conan Doyle wondered at Sherlock Holmes' insight. “By the stickers on your suitcase,” the coachman smiled slyly.
This is another deduction, very short and simple.
Deductive argumentation
Deductive argumentation is the derivation of a substantiated position from other, previously adopted positions. If the advanced position can be logically (deductively) deduced from the already established positions, this means that it is acceptable to the same extent as these positions. Justifying some statements by referencing the truth or acceptability of other statements is not the only function that deduction performs in argumentation processes. Deductive reasoning also serves for verification (indirect confirmation) of statements: from the verified position, its empirical consequences are deduced; confirmation of these consequences is evaluated as an inductive argument in favor of the original position. Deductive reasoning is also used to falsify claims by showing that the consequences that follow from them are false. Unsuccessful falsification is a weakened version of verification: failure to refute the empirical consequences of the hypothesis being tested is an argument, albeit very weak, in support of this hypothesis. And finally, deduction is used to systematize a theory or a system of knowledge, to trace the logical connections of the statements included in it, to build explanations and understandings based on the general principles proposed by the theory. Clarifying the logical structure of a theory, strengthening its empirical base and identifying its general premises is an important contribution to the substantiation of the statements included in it.
Deductive argumentation is universal, applicable in all fields of knowledge and in any audience. “And if bliss is nothing more than eternal life,” writes the medieval philosopher I.S. Eriugena, “and eternal life is the knowledge of the truth, then
bliss is nothing but the knowledge of the truth. " This theological reasoning is a deductive reasoning, namely a syllogism.
The proportion of deductive argumentation in different areas of knowledge is significantly different. It is very widely used in mathematics and mathematical physics, and only occasionally in history or aesthetics. Keeping in mind the scope of application of deduction, Aristotle wrote: "One should not demand scientific evidence from an orator, just as one should not demand emotional conviction from a mathematician." Deductive reasoning is very strong remedy and, like any such tool, should be used in a narrowly targeted manner. An attempt to build argumentation in the form of deduction in those areas or in the audience that are not suitable for this leads to superficial reasoning that can only create the illusion of persuasiveness.
Depending on how widely deductive argumentation is used, all sciences are usually divided into deductive and inductive. The former uses primarily or even solely deductive argumentation. Secondly, such argumentation plays only an obviously auxiliary role, and in the first place is empirical argumentation, which has an inductive, probabilistic character. Mathematics is considered to be a typical deductive science, natural sciences are the model of inductive sciences. However, the division of sciences into deductive and inductive, widespread at the beginning of this century, has now largely lost its significance. It is focused on science, considered in statics, as a system of reliably and definitively established truths.
The concept of deduction is a general methodological concept. In logic, it corresponds to the concept of proof.
Evidence concept
Proof is reasoning that establishes the truth of a statement by bringing other statements, the truth of which is no longer in doubt.
In the proof, the thesis is distinguished - the statement that needs to be proved, and the basis, or arguments, - those statements with the help of which the thesis is proved. For example, the statement "Platinum conducts electricity" can be proven using the following true statements: "Platinum is metal" and "All metals conduct electricity."
The concept of proof is one of the central ones in logic and mathematics, but it does not have an unambiguous definition that is applicable in all cases and in any scientific theories.
Logic does not claim to fully reveal the intuitive, or "naive" concept of proof. Evidence forms a rather vague body that cannot be captured by one universal definition. In logic, it is customary to talk not about provability in general, but about provability within the framework of a given specific system or theory. In this case, the existence of different concepts of proof related to different systems is allowed. For example, a proof in intuitionistic logic and mathematics based on it differs significantly from a proof in classical logic and mathematics based on it. In the classical proof, one can use, in particular, the law of the excluded middle, the law of (withdrawal) double negation, and a number of other logical laws that are absent in intuitionistic logic.
According to the method of carrying out the proofs, they are divided into two types. In direct proof, the challenge is to find convincing arguments from which the thesis logically follows. Indirect proof establishes the validity of the thesis by revealing the fallacy of the assumption, antithesis, opposed to it.
For example, you need to prove that the sum of the angles of a quadrilateral is 360 °. From what statements could this thesis be derived? Note that the diagonal divides the quadrilateral into two triangles. This means that the sum of its angles is equal to the sum of the angles of two triangles. It is known that the sum of the angles of a triangle is 180 °. From these positions, we deduce that the sum of the angles of the quadrilateral is 360 °. Another example. It is necessary to prove that spaceships obey the laws of cosmic mechanics. It is known that these laws are universal: all bodies obey them at any point in outer space. It is also obvious that a spaceship is a space body. Having noted this, we build an appropriate deductive inference. It is a direct proof of the statement under consideration.
In an indirect proof, the reasoning goes, as it were, in a roundabout way. Instead of directly looking for arguments to deduce a provable position from them, an antithesis is formulated, a denial of this position. Further, in one way or another, the inconsistency of the antithesis is shown. By the law of the excluded third, if one of the conflicting statements is wrong, the second must be true. The antithesis is wrong, so the thesis is correct.
Since circumstantial evidence uses the denial of the position being proven, it is said to be evidence from the contrary.
Suppose you need to construct an indirect proof of such a very trivial thesis: "A square is not a circle", An antithesis is put forward: "A square is a circle", It is necessary to show the falsity of this statement. For this purpose, we derive consequences from it. If at least one of them turns out to be false, this will mean that the statement itself, from which the consequence is derived, is also false. In particular, the following consequence is incorrect: a square has no corners. Since the antithesis is false, the original thesis must be true.
Another example. The doctor, convincing the patient that he is not sick with the flu, argues as follows. If there really was a flu, there would be symptoms characteristic of it: headache, fever, etc. But there is nothing of the kind. So there is no flu either.
This, again, is circumstantial evidence. Instead of a direct substantiation of the thesis, an antithesis is put forward that the patient actually has the flu. Consequences are derived from the antithesis, but they are refuted by objective data. This suggests that the flu assumption is wrong. Hence it follows that the thesis "No flu" is true.
Evidence to the contrary is common in our reasoning, especially in controversy. They can be particularly persuasive when used skillfully.
The definition of the concept of proof includes two central concepts of logic: the concept of truth and the concept of logical consequence. Both of these concepts are not clear, and, therefore, the concept of proof defined through them also cannot be classified as clear.
Many statements are neither true nor false, lie outside the "category of truth", Assessments, norms, advice, declarations, oaths, promises, etc. do not describe any situations, but indicate what they should be, in which direction they need to be transformed. The description is required to be true. Good advice (order, etc.) is characterized as effective or expedient, but not true. The saying, "Water boils" is true if the water really boils; the command "Boil the water!" may be appropriate, but has no relation to the truth. Obviously, operating with expressions that have no truth value, one can and should be both logical and demonstrative. Thus, the question arises of a significant extension of the concept of proof, defined in terms of truth. They should cover not only descriptions, but also assessments, norms, etc. The task of redefining the proof has not yet been solved by either the logic of evaluations or the deontic (normative) logic. This makes the concept of proof not entirely clear in its meaning.
Further, there is no single concept of logical consequence. In principle, there are an infinite number of logical systems claiming to define this concept. None of the definitions of logical law and logical consequence available in modern logic are free from criticism and from what is commonly called "the paradoxes of logical consequence."
The model of proof, which in one way or another strives to follow in all sciences, is mathematical proof. It has long been considered to be a clear and undeniable process. In our century, the attitude towards mathematical proof has changed. The mathematicians themselves have broken up into hostile groups, each of which adheres to its own interpretation of the proof. The reason for this was primarily a change in ideas about the logical principles underlying the proof. The confidence in their uniqueness and infallibility disappeared. Logicism was convinced that logic was sufficient to substantiate all mathematics; according to the formalists (D. Hilbert and others), logic alone is not enough for this and logical axioms must be supplemented with mathematical ones; representatives of the set-theoretic direction were not particularly interested in logical principles and did not always indicate them explicitly; the intuitionists, for reasons of principle, considered it necessary not to go into logic at all. The controversy over mathematical proof has shown that there are no criteria of proof that do not depend on time, what is required to prove, or who uses the criteria. Mathematical proof is a paradigm of proof in general, but even in mathematics, proof is not absolute and final.
Deduction is a method of thinking, the consequence of which is a logical conclusion, where a particular conclusion is derived from the general.
“With just one drop of water, a person who can think logically will be able to deduce the existence of the Atlantic Ocean or Niagara Falls, even if he has not seen either one or the other,” the most famous literary detective reasoned. Taking into account the small details imperceptible to other people, he built perfect logical inferences using the method of deduction. It was thanks to Sherlock Holmes that the whole world learned what deduction is. In his reasoning, the great detective always started from the general - the whole picture of the crime with the alleged criminals, and moved to particular moments - he considered everyone individually, everyone who could commit an atrocity, studied the motives, behavior, evidence.
This amazing character of Conan Doyle could guess from which part of the country a person came from by the particles of soil on his shoes. He also distinguished one hundred and forty types of tobacco ash. Sherlock Holmes was interested in absolutely everything, had extensive knowledge in all areas.
What is the essence of deductive logic
The deductive method begins with a hypothesis that a person considers a priori correct, and then he must test it with the help of observations. Books on philosophy and psychology define this concept as an inference built on the principle from the general to the particular according to the laws of logic.
Unlike other types of logical reasoning, deduction deduces a new thought from others, leading to a specific conclusion that is applicable in a given situation.
The deductive method allows our thinking to be more specific and effective.
The bottom line is that deduction is based on the derivation of the particular on the basis of general premises. In other words, this reasoning is based on confirmed, generally accepted and well-known general data, which lead to a logical factual conclusion.
The deductive method is successfully applied in mathematics, physics, scientific philosophy and economics. Doctors and lawyers also need to apply deductive thinking skills, but they can be useful for all professions as well. Even for writers working on books, it is important to understand the characters and draw conclusions based on empirical knowledge.
Deductive logic is a philosophical concept, it has been known since the time of Aristotle, but it began to be intensively developed only in the nineteenth century, when the developing mathematical logic gave impetus to the development of the doctrine of the deductive method. Aristotle understood deductive logic as proofs with syllogisms: reasoning with two messages and one conclusion. Rene Descartes also emphasized the high cognitive or cognitive function of deduction. In his works, the scientist contrasted it with intuition. In his opinion, it directly reveals the truth, and deduction comprehends this truth indirectly, that is, through additional reasoning.
In everyday reasoning, deduction is rarely used in the form of a syllogism or two messages and one conclusion. Most often, only one message is indicated, and the second message, as well-known and recognized by all, is omitted. The conclusion is also not always formulated explicitly. The logical connection between messages and conclusions is expressed by the words "here", "therefore", "means", "therefore".
Examples of using the method
A person who does full deductive reasoning is likely to be mistaken for a pedant. Indeed, reasoning on the example of the following syllogism, such conclusions may be too artificial.
The first part: "All Russian officers cherish military traditions." Second: "All keepers of military traditions are patriots." Finally, the conclusion: "Some patriots are Russian officers."
Another example: "Platinum is a metal, all metals conduct electric current, which means that platinum is electrically conductive."
A quote from an anecdote about Sherlock Holmes: “The cabman greets the hero Conan Doyle, saying that he is glad to see him after Constantinople and Milan. To Holmes' surprise, the cabman explains that he learned this information from the tags on the luggage. " And this is an example of using the deductive method.
Examples of deductive logic in Conan Doyle's novel and McGuigan's Sherlock Holmes
What is deduction in the artistic interpretation of Paul McGuigan becomes clear in the following examples. A quote embodying the deductive method from the series: “This man's bearing is like a former military man. His face is tanned, but this is not his skin tone, as his wrists are not so dark. The face is tired, as after a serious illness. He holds his hand motionless, most likely, he was once wounded in it. " Here Benedict Kamberbech uses the general-to-specific method of inference.
Often deductive conclusions are so truncated that one can only guess about them. It can be difficult to restore deduction in full, indicating two messages and a conclusion, as well as logical connections between them.
Quote from Detective Conan Doyle: "Due to the fact that I have been using deductive logic for so long, inferences arise in my head at such a rate that I do not even notice the intermediate conclusions or the relationship between the two positions."
What deductive logic gives in life
Deduction will be useful in everyday life, business and work. The secret of many people who have achieved outstanding success in various fields of activity is the ability to use logic and analyze any actions, calculating their result.
In the study of a subject, the approach of deductive thinking will allow us to consider the object of study more carefully and from all sides, at work - to make the right decisions and calculate efficiency; and in everyday life - it is better to navigate in building relationships with other people. Hence, deduction can improve quality of life when used correctly.
The incredible interest shown in deductive reasoning in various fields of scientific activity is absolutely understandable. After all, deduction allows one to obtain new laws and axioms from an already existing fact, event, empirical knowledge, moreover, exclusively in a theoretical way, without using it in experiments, solely thanks to observations. Deduction provides a full guarantee that the facts obtained as a result of a logical approach, operations will be reliable and true.
Speaking about the importance of a logical deductive operation, one should not forget about the inductive method of thinking and substantiating new facts. Almost all general phenomena and conclusions, including axioms, theorems and scientific laws, appear as a result of induction, that is, the movement of scientific thought from the particular to the general. Thus, inductive considerations are at the core of our knowledge. True, this approach in itself does not guarantee the usefulness of the knowledge gained, but the inductive method raises new assumptions, connects them with knowledge established empirically. Experience in this case is the source and basis of all our scientific ideas about the world.
Deductive argumentation is a powerful means of knowledge, it is used to obtain new facts and knowledge. Together with induction, deduction is a toolkit for understanding the world.
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Artyom Luchko
The skills of a good detective, such as the ability to quickly "read" a situation and uncover the veil of secrets in the smallest detail, recreating pictures of what happened and psychological portraits of people, are certainly useful for everyone. It's not that hard to acquire and hone them. After exploring the various techniques, we have compiled some useful tips that will help you get a little closer to Sherlock Holmes.
Attention to the details
As you observe people and everyday situations, be aware of the smallest signals during conversations to be more responsive to the course of events. These skills have become trademarks of Sherlock Holmes, as well as the heroes of the series "True Detective" or "The Mentalist". The New Yorker columnist and psychologist Maria Konnikova, author of Mastermind: How to Think Like Sherlock Holmes, says Holmes' thinking is based on two simple things - observation and deduction. Most of us do not pay attention to the details around us, and in the meantime, outstanding (fictional and real) detectives have a habit of noticing everything down to the smallest detail. How can you train yourself to be more attentive and focused?
First, give up multitasking and focus on one thing. The more things you do at the same time, the more likely you are to make mistakes and the more likely you will miss. important information... It is also less likely that this information will be stored in your memory.
Secondly, it is necessary to achieve the correct emotional state. Worry, sadness, anger, and other negative emotions that are processed in the amygdala interfere with the brain's ability to solve problems or absorb information. Positive emotions, on the other hand, improve this brain function and even help you think more creatively and strategically.
Develop memory
Having tuned in the right way, you should strain your memory in order to begin to put everything observed there. There are many methods for training it. Basically, it all comes down to learning to attach importance to individual details, for example, the brands of cars parked near the house, and their numbers. At first you will have to force yourself to memorize them, but over time it will become a habit and you will automatically memorize cars. The main thing when forming a new habit is to work on yourself every day.
Play more often " Memori"And other board games that develop memory. Set yourself the task of memorizing as many objects as possible in random photos. For example, try to memorize as many items as possible from photographs of the "" section of our colleagues from FURFUR in 15 seconds, and then reproduce the entire list on paper.
Memory competition champion and author of Einstein Walks on the Moon on how memory works, Joshua Foer explains that anyone with an average memory ability can greatly expand their abilities. Like Sherlock Holmes, Foer is able to memorize hundreds of phone numbers at once, thanks to the encoding of knowledge in visual images.
His method is to use spatial memory to structure and store information that is relatively difficult to remember. So numbers can be turned into words and, accordingly, into images, which in turn will take place in the palace of memory. For example, 0 can be a wheel, ring, or sun; 1 - with a pillar, pencil, arrow, or even a phallus (vulgar images are remembered especially well, Foer writes); 2 - a snake, a swan, etc. Then you imagine some space you are familiar with, for example, your apartment (it will be your "memory palace"), in which there is a wheel at the entrance, a pencil lies on the bedside table, and behind it is a porcelain swan. This way you can memorize the sequence "012".
Maintaining"Field notes"
As you begin your transformation into Sherlock, start keeping a journal with notes. As the Times columnist writes, scientists train their attention in this way - writing down explanations and capturing sketches of what they are observing. Michael Canfield, an entomologist at Harvard University and author of Field Notes on Science and Nature, says this habit "will force you to make good decisions about what's really important and what's not."
Arthur Conan Doyle. "A study in Scarlet":
“It seems to me that the human brain is like a small empty attic that you can furnish however you want. The fool will drag there any junk that comes to hand, and there will be nowhere to put useful, necessary things, or at best you will not get to the bottom of them among all this blockage. And an intelligent man carefully selects what he puts in his brain attic. He will take only the tools that he will need for work, but there will be many of them, and he will arrange everything in an exemplary order. It is in vain that people think that this small room has elastic walls and they can be stretched as much as necessary. I assure you, the time will come when, acquiring something new, you will forget something of the old. Therefore, it is extremely important that unnecessary information does not crowd out the necessary information. "
Taking notes in the field, whether it's during a regular work planning meeting or a walk in a city park, will develop the right approach to exploring the environment. Over time, you begin to pay attention to small details in any situation, and the more you do it on paper, the faster you will develop the habit of analyzing things on the go.
Focus attention through meditation
Many studies support meditation to improve concentration and attention. It is worth starting to practice from a few minutes in the morning and a few minutes before bedtime. According to John Assaraf, a lecturer and renowned business consultant, “Meditation is what gives control over brain waves. Meditation trains the brain so you can focus on your goals. ”
Meditation can make a person better equipped to receive answers to questions of interest. All this is achieved by developing the ability to modulate and regulate various frequencies of brain waves, which Assaraf compares to four speeds in an auto gearbox: "beta" - with the first, "alpha" - with the second, "theta" - with the third and " delta waves "- from the fourth. Most of us function during the day in the beta range, and this is not so terribly bad. However, what is first gear? The wheels are spinning slowly and the engine wear is quite large. Likewise, people burn out faster and experience more stress and illness. Therefore, it is worth learning how to switch to other gears in order to reduce wear and the amount of "fuel" consumed.
Find a quiet place where nothing will distract you. Be fully aware of what is happening and follow the thoughts that arise in your head, concentrate on your breathing. Take slow, deep breaths, feeling the flow of air from the nostrils to the lungs.
Think critically and ask questions
Once you learn to pay close attention to detail, start converting your observations into theories or ideas. If you have two or three pieces of a puzzle, try to figure out how they fit together. The more puzzle pieces you have, the easier it will be to draw conclusions and see the whole picture. Try to deduce particular positions from general ones in a logical way. This is called deduction. Remember to apply critical thinking to everything you see. Use critical thinking to analyze what you are following closely, and use deduction to build a big picture from those facts.
Describing in a few sentences how to develop your critical thinking skills is not easy. The first step to this skill is to return to the child's curiosity and the desire to ask as many questions as possible. Konnikova says the following about this:
“It's important to learn to think critically. So, when acquiring new information or knowledge about something new, you will not just learn by heart and remember something, but learn to analyze it. Ask yourself: “Why is this so important?”; "How to combine this with the things that I already know?" or "Why do I want to remember this?" Questions like this train your brain and organize information into a network of knowledge. ”
Unleash your imagination
Critical thinking is of no use if you do not learn how to make connections between individual pieces of information. Of course, fictional detectives like Holmes have a superpowered ability to see connections that ordinary people simply ignore. But one of the key foundations of this exemplary deduction is non-linear thinking. Sometimes it is worth giving free rein to your imagination in order to replay the most fantastic scenarios in your head and sort out all possible connections.
Sherlock Holmes often sought solitude in order to reflect and freely explore the issue from all angles. Like Albert Einstein, Holmes played the violin to help himself relax. While his hands were occupied with the game, his mind was immersed in meticulous search for new ideas and problem solving. Holmes even mentions once that imagination is the mother of truth. Having renounced reality, he could take a completely new look at his ideas.
Broaden your horizons
Obviously, an important advantage of Sherlock Holmes lies in his broad outlook and erudition. If you also have the same ease to understand the work of Renaissance artists, the latest trends in the cryptocurrency market and discoveries in the most progressive theories of quantum physics, your deductive methods of thinking have a much better chance of success. You should not put yourself in the framework of any narrow specialization. Reach for knowledge and nurture a sense of curiosity in a wide variety of things and areas.
Maria Konnikova:
“Holmes said that a person should have a clean and tidy“ brain attic ”, but at the same time he himself was literally a walking encyclopedia of knowledge. He read a lot of fiction, which actually had nothing to do with his work. I think this is an important lesson that we can learn. "
(from lat. deductio - derivation) - a logical inference from the general to the particular, from general judgments to particular and other general conclusions. In this case, the general form of deduction is a syllogism, the premises of which form the indicated general position, and the conclusions form the corresponding private judgment. Deduction, or deductive method, is used only in natural sciences, especially in mathematics. The opposite of deduction is induction.
- - the process of inference based on the transition from general provisions to particular ...
Psychological Dictionary
- - - the transition from general knowledge about the subjects of a given class to a single knowledge about a separate subject of this class; one of the methods of cognition. D. - main. means of proof ...
Pedagogical terminological dictionary
- - in the broadest sense of the word, a method of reasoning in which the transition from general knowledge to particular or individual knowledge is carried out ...
The latest philosophical dictionary
- - DEDUCTION. - In modern logic, the term "D." used as a synonym for the more precise but more cumbersome term "deductively correct reasoning" ...
Encyclopedia of Epistemology and Philosophy of Science
- - the transition from premises to a conclusion, based on a logical law, whereby the conclusion with logical necessity follows from the accepted premises ...
Dictionary of logic
- - the reverse induction process, in which, on the basis of general provisions, certain particulars of economic objects, processes are substantiated ...
Terminological dictionary of a librarian on socio-economic topics
- - conclusion according to the rules of logic; a chain of inferences, the links of a cut are connected by a logical relationship. followings ...
Natural science. encyclopedic Dictionary
- - the movement of knowledge from the more general to the less general, particular, deduction of the consequence from the premises. D. is closely related to induction. Logic considers D. as a kind of inference ...
Big psychological encyclopedia
- - a term of modern logic, denoting the derivation of one thought from another, done on the basis of logical laws ...
Encyclopedic Dictionary of Brockhaus and Euphron
- - the transition from general to specific ...
Great Soviet Encyclopedia
-
Modern encyclopedia
- - conclusion according to the rules of logic; a chain of inferences, the links of which are linked by a logical consequence ...
Big encyclopedic dictionary
- - R., D., Pr ....
Spelling dictionary of the Russian language
- - DEDUCTION, -and, wives. The way of reasoning from general provisions to particular conclusions; against. induction...
Ozhegov's Explanatory Dictionary
- - DEDUCTION, deduction, many others. no, wives. ... The method of thinking, in which a new position is deduced by a purely logical way from the previous ones; ant. induction...
Ushakov's Explanatory Dictionary
- - deduction Logical inference, transition from general provisions, laws, etc. to a particular, concrete conclusion ...
Efremova's Explanatory Dictionary
"Deduction" in books
36. Demonstration and deduction
From the book We Play Science. 50 amazing discoveries you and your child will make by Sean Gallagher36. Demonstration and deduction Age: 9-15 months Difficulty level: Medium Research area: cognitive development Experiment Place a plush animal on a flat surface that can "hold" a small ball in its paws. Place a plastic cup on the right and
Deduction
by Swami Suhotra§ 1. REVERSE DEDUCTION
From the book Logic for Lawyers: A Textbook. the author Ivlev Yuri Vasilievich§ 1. REVERSE DEDUCTION Reverse deduction is one of the types of inductive reasoning. Scheme of this type of induction: B1, B2, ..., Bn || = A, if and only if A | = B1? B2? ... Bn and | ?? A, |? IN 1 ? B2? ... Bn, (n? 1). For example, A - judgment “Ivanov committed this crime”. From A and some
Dialectical deduction. Deduction and induction
From the book Marxist Philosophy in the 19th Century. Book one (From the emergence of Marxist philosophy to its development in the 50s - 60s of the XIX century) by the authorDialectical deduction. Deduction and induction Dialectical deduction is a general way of orderly application of the methods of concretization on the path of ascent from the abstract to the concrete, in the course of which there is a movement towards ever new positions and
§ 1. REVERSE DEDUCTION
From the book Logic for Lawyers: A Textbook author Ivlev Yu.V.§ 1. REVERSE DEDUCTION Reverse deduction is one of the types of inductive reasoning. Scheme of this type of induction: B1, B2, ..., Bn || = A, if and only if A | = B1? B2? ... Bn and |? ¬ A, |? IN 1 ? B2? ... Bn, (n? 1). For example, A - judgment “Ivanov committed this crime”. From A and some collection
DEDUCTION
From the book The Art of Thinking Right the author Ivin Alexander ArkhipovichDEDUCTION “One drop of water ... a person who knows how to think logically can draw a conclusion about the existence of the Atlantic Ocean or Niagara Falls, even if he has not seen either one or the other and has never heard of them ... By the nails of a person, by his sleeves, shoes, fold
Déduction
From the book Philosophical Dictionary the author Comte Sponville AndréDeduction (D? Duction) To reason by the method of deduction means to deduce from true or supposedly true judgments (principles or premises) other judgments that necessarily follow from them. By deduction, Descartes writes, we mean “all that
Deduction
From the book Great Soviet Encyclopedia (DE) of the author TSBDeduction
From the book Encyclopedic Dictionary (D-D) author Brockhaus F.A.DEDUCTION
From the book The Newest Philosophical Dictionary the author Gritsanov Alexander AlekseevichDEDUCTION (lat. Deductio deduction) - in the broad sense of the word, a method of reasoning, in which the transition from general knowledge to particular or individual knowledge is carried out. In this sense, dialectic is opposed to induction as a transition from the individual and the particular to the general. In modern
Deduction
From the book Adobe Flash. Create arcades, puzzles, and other games with ActionScript the author Rosenzweig GaryDeduction Source file: Deduction.fla The following game is completely based on logic. One of its most popular variants (for two players) is known as "Mastermind". The goal of the game is to guess an arbitrary sequence of five colors. The player starts by guessing.
Deduction
From the book Intellect. How your brain works the author Sheremetyev KonstantinDeduction Wisdom is the science of principles. Aristotle The first person who began to develop the tools of thinking was the ancient Greek philosopher Aristotle, who lived in 384–322. BC e. Aristotle systematically developed the power of his mind. As a result, he became one of the most
Deduction
From the book Shadow and Reality by Swami SuhotraDeduction A method of inference in which a sentence is the result of some authoritative evidence or a priori knowledge [transition from the general to the particular]. See Abduction, Aroha / Avaroha, Hypothetical-deductive method, Induction,
How does deduction work?
From the book Boost Your Brain Using the Sherlock Holmes Method the author Kuzina Svetlana ValerievnaHow does deduction work? Remember, as Holmes said: "Throw away all the impossible, and what remains will be the answer, no matter how incredible it may seem." This is the method of deduction (Latin deductio - deduction) means a method of thinking in which a particular position is logical
Induction and deduction
From the book Own Counterintelligence [Practical Guide] the author Zemlyanov Valery MikhailovichInduction and deduction Induction (from the Latin "induction", ie guidance) is the process of movement of thought from single phenomena to general conclusions, a means of obtaining general knowledge from knowledge about individual aspects (objects, phenomena). Induction allows you to obtain new knowledge