Deduction is a method of thinking, the consequence of which is a logical conclusion, where a particular conclusion is deduced from a general one.
“From just one drop of water, a person who knows how to think logically can deduce the existence of the Atlantic Ocean or Niagara Falls, even if he has not seen either one or the other,” this is how the most famous literary detective reasoned. Taking into account small details invisible to other people, he built impeccable logical conclusions 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 specific moments - he considered each individual, everyone who could commit the crime, studied the motives, behavior, evidence.
This amazing Conan Doyle hero could guess from the soil particles on his shoes which part of the country a person came from. He also distinguished one hundred and forty types of tobacco ash. Sherlock Holmes was interested in absolutely everything and had extensive knowledge in all areas.
What is the essence of deductive logic
The deductive method begins with a hypothesis that a person believes to be true a priori, and then he must test it through 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 derives a new idea from others, leading to a specific conclusion applicable to a given situation.
The deductive method allows our thinking to be more specific and effective.
The bottom line is that deduction is based on deducing the particular on the basis of general premises. In other words, this is reasoning based on confirmed, generally accepted and generally known general data, which leads to a logical factual conclusion.
The deductive method is successfully used in mathematics, physics, scientific philosophy and economics. Doctors and lawyers also need to use deductive reasoning skills, but they are useful for any profession. Even for writers working on books, the ability to understand characters and draw conclusions based on empirical knowledge is important.
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 developing mathematical logic gave impetus to the development of the doctrine of the deductive method. Aristotle understood deductive logic as evidence with syllogisms: reasoning with two premises 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 extremely rarely used in the form of a syllogism or two premises and one conclusion. Most often, only one message is indicated, and the second message, as well-known and accepted by everyone, is omitted. The conclusion is also not always formulated explicitly. The logical connection between premises and conclusions is expressed by the words “here,” “therefore,” “therefore,” “therefore.”
Examples of using the method
A person who engages in full deductive reasoning is likely to be mistaken for a pedant. Indeed, when reasoning using the following syllogism as an example, such conclusions may be too artificial.
First part: “All Russian officers carefully preserve 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 electricity, which means platinum is electrically conductive.”
Quote from a joke about Sherlock Holmes: “The cabman greets Conan Doyle’s hero, saying that he is glad to see him after Constantinople and Milan. To Holmes’ surprise, the cab driver 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 series
What deduction is in the artistic interpretation of Paul McGuigan becomes clear in the following examples. A quote that embodies the deductive method from the series: “This man has the bearing of a former military man. His face is tanned, but this is not his skin tone, since his wrists are not so dark. The face is tired, as if after a serious illness. He holds his hand motionless, most likely he was once wounded in it.” Here Benedict Cumberbatch uses the method of inference from the general to the specific.
Often deductive conclusions are so limited that they can only be guessed at. It can be difficult to restore deduction in full, indicating two premises and a conclusion, as well as logical connections between them.
Quote from detective Conan Doyle: “Because I have been using deductive logic for so long, conclusions arise in my head so quickly that I do not even notice intermediate conclusions or relationships between two positions.”
What does deductive logic give 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 lies in the ability to use logic and analyze any actions, calculating their outcome.
When studying any subject, the deductive thinking approach will allow you to consider the object of study more carefully and from all sides; at work, you will be able to make the right decisions and calculate efficiency; and in everyday life - to better navigate in building relationships with other people. Therefore, 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 you to obtain new laws and axioms from an existing fact, event, empirical knowledge, moreover, exclusively through theoretical means, without applying it experimentally, solely through observations. Deduction provides a complete guarantee that the facts obtained as a result of the logical approach and operation will be reliable and true.
Speaking about the importance of the logical deductive operation, we should not forget about the inductive method of thinking and justifying 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 reasoning is the basis of our knowledge. True, this approach in itself does not guarantee the usefulness of the acquired knowledge, but the inductive method raises new assumptions and 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 cognition, used to obtain new facts and knowledge. Together with induction, deduction is a tool for understanding the world.
DEDUCTIVE METHOD is a method of constructing scientific theories, a specific feature of which is the use of deductive inference techniques ( Deduction ). In philosophy, there have been attempts to draw a sharp line between the deductive method and other methods (for example, inductive), to interpret deductive reasoning as inexperienced and to excessively exaggerate the role of deduction in science. In fact, deduction and induction are inextricably linked, and the structure of deductive reasoning is determined by centuries-old practical-cognitive human activity. The deductive method is one of the possible methods for constructing scientific knowledge. It is used, as a rule, after empirical material has been accumulated and theoretically interpreted for the purpose of systematizing it, more rigorously and consistently deriving all consequences from it, etc. At the same time, new knowledge is obtained - in the form of many consequences of the deductive theory and how a set of possible interpretations of a deductively constructed theory. The general scheme of organization of deductive systems (theories) includes: 1) the initial basis, i.e., a set of initial terms and statements: 2) the logical means used (rules of inference and definition); 3) a set of statements (proposals) obtained from (1) by applying (2). When studying such theories, the relationships between their individual components, abstracted from the genesis and development of knowledge, are analyzed. Therefore, it is advisable to consider them as a kind of formalized languages that can be analyzed either syntactically (when the relationship between the signs and expressions included in the language is studied without taking into account their extra-linguistic meaning), or semantically (when the relationship between signs and expressions of the system is considered from the point of view of their meaning) aspects. Deductive systems are divided into axiomatic (Axiomatic method) and constructive (Constructive method). The deductive method, when used in knowledge based on experience and experiment, acts as a hypothetico-deductive method. The analysis of the deductive method of constructing scientific knowledge began already in ancient philosophy (Plato, Aristotle, Euclid, the Stoics), and occupied a lot of space in the philosophy of modern times (Descartes, Pascal, Spinoza, Leibniz, etc.), but the principles of the deductive organization of knowledge were fully and clearly formulated only at the end of the 19th - beginning of the 20th century. (in this case, the apparatus of mathematical logic was widely used). Until the beginning of the 20th century. The deductive method was used mainly in the fields of mathematics and logic. In the 20th century, attempts at deductive (in particular, axiomatic) construction also became widespread. non-mathematical disciplines - individual sections of physics, biology, linguistics, sociology, etc.
Philosophical Dictionary. Ed. I.T. Frolova. M., 1991, p. 106-107.
Through deduction, truth is revealed both in the natural sciences and in everyday life. People use the ability to reason logically, which in the general understanding is deduction, in everyday life, at work, in games and other activities not related to science. The science of logic studies these processes. Deduction is based on isolating the particular from general judgments through logically processed inferences. To better understand the subject of discussion, it is necessary to understand what deduction is and explore all the points related to it.
What is an inference?
First, you need to understand that Logic considers this concept as a form of thinking in which a new judgment (that is, a conclusion or conclusion) is born from several premises (forms of judgment).
For example:
- All living organisms consume moisture.
- Absolutely all plants are living organisms.
- Conclusion - all plants consume moisture.
So, the first and second judgments in this example are the premise, and the third is the conclusion (conclusion). The incorrectness of one of the messages can lead to If the messages are not related to each other, it is impossible to draw a conclusion.
Inferences are divided into indirect and direct. In the latter, the conclusion is drawn from one premise. That is, they are transformed simple judgments.
In indirect inferences, the analysis of several premises leads to the formation of a conclusion. Such conclusions are divided into three types: deductive, inductive and analogical conclusions. Let's look at each of them.
Deductive reasoning
Inference based on deduction provides a conclusion for a particular case from a general rule.
For example:
- Monkeys love bananas.
- Lucy is a monkey.
- Conclusion: Lucy loves bananas.
In this example, the first premise is a general rule, in the second, a particular case is included in the general rule and, as a consequence, on this basis a conclusion is drawn regarding this particular case. If all monkeys love bananas, and Lucy is one of them, then she loves them too. The example clearly explains what deduction is. This is a movement from more to less, from general to specific, in which the aspect of knowledge is narrowed, provoking a reliable conclusion.
Inductive Inference
The opposite of deductive reasoning is inductive reasoning, in which a general pattern is derived from some particular cases.
For example:
- Vasya has a head.
- there is a head.
- Kolya has a head.
- Vasya, Petya and Kolya are people.
- Conclusion - all people have a head.
In this case, the first three premises are special cases, generalized by the fourth to one class of objects, and the conclusion states a general rule for all objects of this class. Unlike deduction, in inductive inferences reasoning proceeds from the lesser to the greater, from the particular to the general; therefore, the conclusions are not reliable, but probabilistic. After all, transferring special cases to the general group is fraught with errors, since in any case there may be exceptions. The probabilistic nature of induction is, of course, a minus, but there is a huge plus in comparison with deduction. What is deduction? working to narrow knowledge, its concretization, analysis and analysis of known facts. Induction, on the contrary, encourages the expansion of knowledge, the creation of something new, the synthesis of new conclusions and judgments.
Analogy
The next type of inference is based on analogy, that is, the similarity of objects to each other is assessed. If objects are similar in some characteristics, their similarity in others is also allowed.
An example of inference by analogy is the testing of large ships in a pool, in which their properties are mentally transferred to the open water spaces of the seas and oceans. The same principle is used when studying the properties of micromodels of bridges.
It should be remembered that the conclusions of analogy, like induction, are probabilistic.
What is the use of deduction?
As mentioned at the beginning of the article, deductive reasoning can be made by any person in the course of life, and such conclusions affect many areas of life in addition to scientific ones. The deductive way of thinking is very useful for law enforcement, investigative and judicial officers (for the “Sherlocks” of our time).
But no matter what a person does, deduction is always useful. In professional activities, it will allow you to make the most rational and competent far-sighted decisions, in studies - to master the subject faster and more thoroughly, and in everyday life - to better build relationships with people and understand those around you.
Methods for developing deduction
Many people these days strive for self-development and tend to come to understand the importance of having good deductive reasoning. How to develop deduction correctly?
The development of deduction can be facilitated by special games, as well as the introduction of a new way of thinking into everyday life. Basic tips for its development can be compiled into the following blocks:
- Awakening interest. Any material that is studied should be of interest. This will allow you to better understand all the intricacies of the subject and achieve the desired level of understanding.
- Depth of study. You cannot study subjects superficially; only a thorough analysis will give a positive result.
- Broad outlook. People with developed thinking often have knowledge in many areas of life - culture, music, sports, science, etc.
- Flexibility of thinking. What is deduction without flexibility of thinking? This is an almost useless attribute. To develop such flexibility, it is necessary to try to bypass the generally accepted paths and schemes, to find new aspects of the vision of the issue that will prompt the correct and sometimes unexpected solution. A critical approach to even the most ordinary and familiar situations will allow you to make the optimal and, very importantly, independent decision.
- Combination. Try to think in different ways at the same time - combine inductive and deductive reasoning.
Deduction is a special method of thinking based on the ability to build a logical connection and draw small private conclusions from the overall picture. How did the well-known legendary hero Sherlock Holmes use this?
Sherlock Holmes method
Sherlock Holmes' deductive method can be described in one phrase that the detective uttered in A Study in Scarlet: "All life is a huge chain of causes and effects, and we can know its nature one by one." Undoubtedly, everything in life is chaotic and sometimes unpredictable, but despite this, the skills that the detective possessed helped him solve even the most complicated crimes.
Observation and details
Sherlock Holmes collected as much information as possible, analyzed various scenarios for the development of events and looked at them from different angles. This allowed the detective to discard the unimportant, thus, the hero of Arthur Conan Doyle singled out one or more more significant ones from the many possible versions.
Concentration
A detached face, ignoring people and their questions, as well as events around oneself - this is how Conan Doyle portrays his hero. However, such behavior is by no means a sign of bad taste. No. This is the result of a special focus on the investigation. Sherlock Holmes constantly thinks about all possible options for solving a problem, abstracting from external factors.
Interest and outlook
The detective's main weapon was his broad outlook. It is worth remembering how he could easily determine from soil particles where a person came from in England. He was interested in literally everything, especially what escaped the attention of ordinary people. He was a specialist in criminology and biochemistry, played the violin remarkably, was versed in opera and music, knew several foreign languages, practiced fencing and knew how to box. A multifaceted personality, isn't it?..
Palaces of the Mind
The deduction method is based on memorizing information using associations. The famous detective worked with a large amount of information. And in order not to get confused in it, he used a method called “paintings of the mind.” By the way, it is far from new; its essence was known to the ancient Greeks. Each fact, information, knowledge is tied to a specific object in the room, for example, a door, window, etc. This made it easier for the detective to remember information that came to him almost hourly.
Sign language
Sherlock Holmes was a wonderful psychologist. Observing the behavior of a particular person, the detective paid attention to facial expressions and gestures, as a result of which he could easily determine whether his client/suspect was lying or not. The ability to notice details - behavior, manner of speaking, dressing - helps to create an overall picture of a person’s life.
Intuition
Sherlock Holmes' intuition was rather based not on a sixth sense, but on experience. But the line between the voice of the subconscious and high qualifications in work is quite blurred. Only the person himself can draw this fine line between the assumption and the action itself.
Practice
The method of deduction can only be developed through practice. Sherlock Holmes constantly practiced logic, even in his free time. This allowed him to constantly keep his mind “on its toes.” But without interesting things to do, he was bored and mopey.
The benefits of deduction
Deductive thinking skills will be useful in everyday life and work. The secret of many successful people is the ability to think logically and analyze their actions, predicting the outcome of events. This helps them avoid patterns and achieve greater success in various areas:
In studies - helps to quickly master the subject being studied;
In work activity - make the right decisions and plan your actions several steps ahead;
In life - to understand people well and build effective relationships with others.
Thus, the deduction method will help make life much easier and avoid many unpleasant situations, as well as quickly achieve your goals.
How to develop deductive thinking
Mastering the way of thinking we are considering is a long and painstaking work on oneself, but at the same time it does not present any particular difficulties. The deduction method requires the participation of common sense, but emotions must be relegated to the background, they will only interfere with the process. There are a number of rules that will help develop a deductive way of thinking at any age.
1. If you are determined to achieve a positive result in this field, then you need to start reading a lot. But not glossy magazines and newspapers - classical literature and modern detective stories or novels will be useful. While reading, you need to think about the plot and remember the details. Compare the “material covered”: eras, genres, etc.
2. In everyday life, try to pay attention to little things: people’s behavior, their clothes, gestures, facial expressions, speech. This will help develop your powers of observation and teach you analysis. It would be nice to enlist the support of a like-minded person with whom you can discuss what you saw, and in the process of conversation you will learn to express your thoughts logically and build a chronological sequence of events.
3. Solving logical problems and puzzles will help you master deductive thinking skills.
4. Pay attention to your actions, analyze why you did what you did in a certain situation, look for other possible options for getting out of it and think about what result could have happened in this case.
5. The development of deductive thinking requires memory training. This is necessary in order to cover a large amount of information and keep it in your head. It is important to note that memory training needs to be done constantly. Scientists have found that a person loses acquired skills and abilities if brain activity is interrupted for some period of time (say, on vacation). Well-known methods will help develop memory:
Memorize a certain number of words by ear;
Repeat the phrases you read word for word;
List items.
It should be remembered that there are several sources of information perception: auditory, voice, visual and tactile. At the same time, it is important to develop everything at the same time, focusing on weaknesses. To simplify the memorization process, you can come up with your own system of encoding and associations.
6. But you should not completely rely on memory, since its possibilities are not unlimited. You need to train yourself to take notes - in the form of graphs, tables, lists. This useful habit will help you find connections and create logical chains.
7. It is important to constantly learn new knowledge. They may not even be related to social life and interpersonal relationships. It is recommended to read fiction - this will develop impressionability and the ability to think figuratively. Special attention must be paid to the development of special knowledge, such as psychology, physiognomy, sign language. They will help analyze human behavior in certain situations.
8. Practice plays an important role in mastering deductive thinking. Its essence is to create a problem situation and find a way out of the current situation. To do this, it is necessary to put forward a hypothesis and determine ways to solve the problem. Next, considering various approaches, you need to find the best option. Try to conduct a comparative analysis of the expected paths of development of events.
The deductive way of thinking is a fascinating journey through the expanses of logic. By making an effort and spending some time practicing, you will be able to pick up the keys to any locks using deduction and experience for yourself what it means to be Sherlock Holmes.
In different life situations, one or another type of thinking helps a person. If we talk about such a concept as logic, then there is a distinction between deductive and inductive methods. In this article we will talk about what deduction and induction are, but we will dwell in more detail on the first term.
The Legendary Detective Method
Many have repeatedly admired how Conan Doyle's famous character Sherlock Holmes solved the most intricate and mysterious crimes. The deductive method of thinking helped him in this. What is it?
First, let's define the term. The word “deduction” is translated from Latin as “deduction.” This is a special type when a logical connection is built from the general to the specific.
In a long chain of causes and effects there is that one link that is the key to what we are looking for. It was the ability to find this link that helped the detective unravel mysterious circumstances, working amid the unpredictability and chaos of life.
With such a conclusion, it is possible to achieve a clear and specific understanding of the situation. How did this help the detective? He took as a basis the overall picture of the crime, which included all the participants in the event, their capabilities, style of behavior, motives and, using logical conclusions, accurately determined which of them was the criminal.
What other examples of deductive thinking can you give? Let's look at the discussion about metals and their ability to conduct current. Here's an example:
- All metals conduct current.
- Silver is a metal.
- This means that silver also conducts current.
Of course, this is a very simplified conclusion, because this reasoning does not take into account exact knowledge, experience and specific facts. Only this allows you to develop the right style of thinking. Otherwise, a person comes to a completely erroneous understanding, for example in the following judgment: “All women are liars, you are a woman, which means you are also a liar.”
Pros and cons of using deduction
Now let's talk about the advantages and disadvantages of this thinking style.
To begin with, the pros:
- The ability to use it even if there is no prior knowledge in this particular field of study.
- Save time and reduce material volume.
- Development of evidence-based and logical way of thinking.
- Improving cause-and-effect thinking.
- Ability to test hypotheses.
And now the cons:
- Very often a person receives ready-made knowledge, and therefore does not study the information and does not accumulate personal experience.
- It is often difficult to bring each individual case under one rule.
- It is not used to discover new laws and phenomena, as well as to formulate hypotheses.
If a person studies, then logical thinking helps him quickly and easily master the necessary material. If he works, then he will need the ability to make the only correct decision and evaluate the consequences of different options for his actions, knowing where they will lead. In everyday life, a person begins to better understand people and builds effective and trusting relationships with them.
Two thinking styles - two conclusions
Induction - in philosophy it is also one of the methods of reasoning and research. Unlike the deductive style of thinking, induction, on the contrary, leads from the particular to the general. It is believed that the latter method is often dubious and can only be trusted with some degree of probability.
In fact, every reasonable person uses both principles in his life, but rarely realizes it. So, if in the morning you look out the window and see that the ground is wet and it has become cold, then it is quite natural to assume that it rained at night. We know that if we go to bed late, then getting up early will be difficult for us.
In what areas of life and how are the methods of deduction and induction used:
- Logic is the creation of new methods of cognition.
- Economics is the development of particular facts based on general theories.
- Physics - understanding laws and hypotheses.
- Mathematics is an opportunity to quickly remember and understand the material.
- Psychology is the study of disorders in the functioning of thinking.
- Management is the only correct solution.
- Sociology – analysis of data about society.
- Medicine is an opportunity to make the only correct decision in a given situation.
Listed above are not all areas of human life where the method of deduction turns out to be useful or even the only correct one. It also helps in everyday life, allowing you to draw correct conclusions about the people around you and build relationships with them.
The use of both methods is important both in everyday life and in a professional environment. Thus, a doctor cannot diagnose a patient until he analyzes all the information available to him: tests, symptoms, the patient’s appearance, and much more.
That is why, in order to successfully use different methods in your work, you need to know a lot and have a sufficient amount of experience. So, this is the end of the theory of deduction, let's now talk about practical techniques.
Developing thinking
So how do you develop deduction? It's not difficult to learn. To do this, you can observe, play, solve problems and expand your knowledge. Let's look at all the proposed methods in more detail.
All this helps to understand the character and intentions of the interlocutor. When you walk down the street, look at passers-by and think about where the person might be going, what mood he is in, what could upset him or make him laugh, what his marital status is, etc.
2. Play. All kinds of games, such as Sudoku, chess, puzzles and others, are very helpful in developing memory.
3. Learn new things. It is important for a person to work to constantly expand his horizons, learn new information, and not only in his specialty or work, but also in various other areas.
4. Be meticulous. If you start studying something, do it as comprehensively and thoroughly as possible. It is important that this subject arouses your interest, only then the desired result will appear.
6. Develop attention. It is important that your attention is not diverted to other things when you need to focus on the task at hand. It is also important to train involuntary attention and notice things that usually do not cause you any interest. To do this, simply observe familiar things in an unusual environment.
Now let’s try to answer the question of why develop deductive abilities at all. A person is a conscious being, and only he is given the opportunity to make informed decisions based on appropriate conclusions and assessments. But how often do people act impulsively, on emotions... But now you know the definition of the word “deduction” and will be able to apply the information received to your personal experience. Author: Natalya Zorina