Thinking is an important cognitive process for a person, thanks to which he gains new knowledge, develops and becomes better. There are different thinking techniques that can be used at any time and in different situations.
What is this deduction?
A method of thinking by which logical conclusions are drawn about a specific subject or situation based on general information, is called deduction. Translated from Latin, this word means “inference or logical conclusion.” A person uses generally known information and specific details, analyzes, putting the facts together in a certain chain, and finally draws a conclusion. The deduction method became famous thanks to books and films about detective Sherlock Holmes.
Deduction in philosophy
They began to use it to build scientific knowledge back in ancient times. Famous philosophers, for example, Plato, Aristotle and Euclid used it to make inferences based on existing information. Deduction in philosophy is a concept that different minds have interpreted and understood in their own way. Descartes considered this type of thinking to be similar to intuition, with the help of which a person can gain knowledge through reflection. Leibniz and Wolff had their own opinions about what deduction is, considering it the basis for obtaining true knowledge.
Deduction in psychology
Thinking is used in different directions, but there are areas aimed at studying deduction itself. The main purpose of psychology is to study the development and impairment of deductive reasoning in humans. This is due to the fact that since this type of thinking involves a movement from general information to specific analysis, all mental processes are involved. The theory of deduction is studied in the process of forming concepts and solutions to various problems.
Deduction - advantages and disadvantages
To better understand the capabilities of the deductive method of thinking, you need to understand its advantages and disadvantages.
- Helps save time and reduce the amount of material presented.
- Can be used even when there is no prior knowledge in a particular area.
- Deductive reasoning contributes to the development of logical, evidence-based thinking.
- Provides general knowledge, concepts and skills.
- Helps test research hypotheses as plausible explanations.
- Improves the causal thinking of practitioners.
- In most cases, a person gains knowledge in finished form, that is, does not study information.
- In some cases, it is difficult to bring a specific case under a general rule.
- Cannot be used to discover new phenomena, laws or formulate hypotheses.
Deduction and induction
If we have already understood the meaning of the first term, then as for induction, it is a technique for constructing a general conclusion based on particular premises. He does not use logical laws, but relies on some psychological and factual information, which is purely formal. Deduction and induction are two important principles that complement each other. For a better understanding, it is worth considering an example:
- Deduction from the general to the specific involves obtaining from one truthful information another, and it will be the truth. For example, all poets are writers, conclusion: Pushkin is a poet and writer.
- Induction is an inference that arises from knowledge of some objects and leads to generalization, therefore they say that there is a transition from reliable information to probable information. For example, Pushkin is a poet, like Blok and Mayakovsky, which means that all people are poets.
How to develop deduction?
Every person has the opportunity to develop deductive thinking, which is useful in different life situations.
- Games. To develop memory you can use different games: Chess, puzzles, Sudoku and even card games force players to think through their moves and memorize cards.
- Problem solving. That's when the school curriculum in physics, mathematics and other sciences comes in handy. While solving problems, slow thinking is trained. You should not stop at one solution option and it is recommended to look at the problem from a different point of view, proposing an alternative.
- Expansion of knowledge. The development of deduction implies that a person must constantly work to expand his horizons, “absorbing” a lot of information from different areas. This will help you build your conclusions in the future, based on specific knowledge and experience.
- Be observant. Deduction is impossible in practice if a person does not know how to notice important details. When communicating with people, it is recommended to pay attention to gestures, facial expressions, voice timbre and other nuances, which will help to understand the intentions of the interlocutor, calculate his sincerity, and so on. While on public transport, observe people and make various assumptions, such as where the person is going, what he is doing, and much more.
Deduction - exercises
- Use any pictures, and it’s better if they have a lot of small details. Look at the image for a minute, trying to remember how you can more details, and then write down everything that remains in your memory and check it. Gradually reduce your viewing time.
- Use words that are similar in meaning and try to find as many differences as possible in them. For example: oak/pine, landscape/portrait, poem/fairy tale, and so on. Experts also recommend learning to read words backwards.
- Write down the names of people and the dates of a specific event in their lives. Four positions are enough. Read them three times, and then write down everything you remember.
Deductive method of thinking - books
One of important ways For the development of deductive thinking is reading books. Many people don’t even suspect how much benefit this has: memory training, broadening of horizons, etc. To apply deductive method, it is necessary not just to read the literature, but to analyze the situations described, remember, compare and carry out other manipulations.
- For those who are interested in what deduction is, it will be interesting to read the work of the author of this method of thinking, René Descartes, “Discourse on the Method for Correctly Directing Your Mind and Finding Truth in the Sciences.”
- Recommended literature includes various detective stories, for example, the classic A. K. Doyle “The Adventures of Sherlock Holmes” and many worthwhile authors: A. Christie, D. Dontsova, S. Shepard and others. When reading such literature, it is necessary to use deductive thinking to guess who the criminal might be.
Life constantly forces us to make decisions. And few people think about the fact that thoughts about what is happening are built according to very specific schemes. Let's explore this topic in more detail, or rather, find out how deduction differs from induction.
Definition
Deduction– a reasoning in which the existing premises (statements) become the basis for drawing a conclusion. Example: any number that is a multiple of four is also divisible by two (premise); eight is a multiple of four (premise); therefore eight is divisible by two (conclusion).
Induction- this is a mental method in which, on the basis of individual facts, a certain big picture. Example: raspberries – sweet, strawberries – sweet, grapes – sweet; raspberries, strawberries, grapes - berries; This means that all the berries are sweet.
Comparison
We are talking about two opposing ways of thinking. A typical model of deduction involves moving in some reasoning from the general to the specific. In induction, on the contrary, knowledge about individual units leads to the conclusion that all objects in this series have the same characteristics.
The difference between deduction and induction is that in reasoning carried out in the first way, pure logic operates. This allows us to draw error-free conclusions. But there is one condition: the original provisions must be true. Let's give an example: any drink is a liquid (a valid premise); compote is a drink (a reliable premise); It follows from this that compote is a liquid (true conclusion).
In turn, inductive inference is not derived strictly in accordance with logic, but through guesswork and some ideas. As a result, the resulting consequence is only probabilistic and requires verification. Even with true premises, an incorrect conclusion may result. Example: Misha is a kindergartener, Kostya is a kindergartener, Sveta goes to kindergarten(Truth); Misha, Kostya, Sveta are children (true); all children attend kindergarten (false - there are those who are at home before school).
It should be noted that the most reliable knowledge is provided by complete induction - one in which each of a specific class of objects is examined, and only after that a general judgment about the set is formed. But in practice this is not always possible. Often only the particular is considered, and then the definition is transferred to the entire group. In order for such conclusions to leave no doubt about their veracity, it is necessary to resort to repeated experiments and apply theoretical thinking.
Concluding the conversation on the topic of what is the difference between deduction and induction, it is worth mentioning that in scientific research the two described methods are organically related. Through induction, many important hypotheses are put forward, and deduction allows us to obtain consequences from them that are subject to justification or refutation.
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 Atlantic Ocean or Niagara Falls, even if he saw neither one nor 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 picture - 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 at 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– better navigate in building relationships with other people. Therefore, deduction can improve the quality of life when correct use this approach.
The incredible interest shown in deductive reasoning in various fields scientific activity, absolutely explain. 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 a 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.
Induction is a way to test a hypothesis. Induction in philosophy is a method of thinking with which one can find one common feature and thus classify objects and phenomena. To clarify the results of inductive thinking in science, deduction is also used - a method of thinking opposed to induction, for which it is necessary to come from a general conclusion to a particular one.
History of the term
The term “induction” was first mentioned in the works of Socrates. But he put a different meaning into it. Socrates called induction the knowledge that consists in searching general definition to describe several special cases. Aristotle describes induction as a comparative inference in which the mental process evaluates particular cases and reduces them to a common denominator. The thinker opposed induction to syllogism aimed at finding an average value.
During the Renaissance, Aristotle's legacy was reevaluated and criticized. In scientific circles, syllogism as a research method is denied, and the inductive method is considered the only way to obtain reliable information. F. Bacon is considered the creator of the modern inductive method. He refuses to use syllogism, but at the same time his theory of induction does not contradict syllogism at all. Bacon's inductive method is based on the principle of comparison. To come to a conclusion, it is necessary to analyze all cases and derive a pattern, that is, make a generalization.
The next attempt to abandon the syllogism in favor of induction was the study of J. Mill. He believed that in order to obtain a syllogical conclusion it is necessary to go from particular to particular, without striving for the general. He sees an inductive conclusion as an analysis of phenomena of the same order. All inferences require the use of four methods:
- Consent method. If the phenomena being studied have at least one common feature, it is likely to be the root cause.
- Method of difference. If two cases being compared have only one difference, but are otherwise similar, then this difference is the cause of the phenomenon.
- Residue method. For that part of the phenomenon that cannot be explained by an obvious cause, it is necessary to look for justification among the remaining versions. At first glance they often seem incredible, but one will eventually prove to be a credible explanation.
- Method of corresponding changes. If several phenomena change under the influence of one circumstance, there is likely a causal relationship between them.
It is noteworthy that the methods that Bacon presents as inductive have a deductive component. In particular, the residual method works on the principle of eliminating versions, moving from the general to the specific.
Features of the inductive method
In science, there are two types of inductive method: complete induction and incomplete induction.
Full induction
With complete induction, all objects from the group are subjected to mental analysis in turn. They are identified with a given feature. If each object meets the stated condition, we can confidently assume that the objects have a common nature.
Incomplete induction
The main difference between incomplete induction is the inability to make a reliable inference. In case of incomplete induction, comparison is made individual elements objects, and makes an assumption based on the result. Incomplete induction allows us to draw only a particular conclusion, while complete induction tends to the general.
How to use deductive and inductive approaches correctly
Using induction as the only method of searching for information does not provide an objective picture.
Inductive and deductive methods of reasoning have opposite ways of moving thought, but they do not contradict each other, but complement. Deductive reasoning requires a general statement, while inductive reasoning collects particular cases, bringing them under one theory. To get a result close to the truth, you must use both methods at once. This allows you to test each theory and weed out implausible ones. And from the remaining ones, by comparison, select one that will meet all the specified requirements.
It is assumed that Descartes himself and others in the scientific community who used the method of induction were actually using a combination of methods. Using one method increases the risk of formulating false conclusions. If the researcher cannot bring all subjects under a common factor, he will be tempted to discard inconsistencies and thereby distort the conditions of the experiment and get the wrong result.
The role of thinking methods in psychology
Deduction and induction are methods of thinking that need to be used in combination. Studying mental processes, responsible for the development, interrelation and interaction of thought processes - one of the tasks of psychology. The form of manifestation of deduction and induction in psychology is called deductive thinking.
People who seek therapy use incomplete induction and arrive at erroneous conclusions. For example, a wife who cheated on her husband has red hair, which means all women with red hair are cheaters. Sometimes, the conclusions obtained as a result of deductive thinking are so divorced from reality that they pose a threat to the patient’s life. If a person decides that water is dangerous for him, he will completely refuse to use it. Without treatment he will die. Water is a source of stress for him, causing a panic reaction. A person cannot cope with such a burden on the psyche on his own, and at the moment of an emotional outburst he becomes dangerous to others.
This unconscious use of inductive reasoning is called fixation. The way to get rid of fixation will be correct deductive thinking, but its development, like any other method of therapy, should be under the supervision of a psychotherapist.
- Solution logical problems. Classic method deductive reasoning is mathematical thinking. To solve a problem, a person uses logic, and this contributes to the development of the skill of distinguishing a false judgment from a plausible one.
- Expanding your horizons. In essence, this is replenishing the knowledge base with any information that is interesting to a particular person. You don't have to read textbooks for this. New information can be obtained by watching films or websites, communicating with other people, traveling.
- Development of accuracy. The ability to specify helps to select the correct criterion by which to evaluate phenomena.
- Flexibility of mind. A small amount of knowledge contributes to ossification of the mind. Having a limited set of typical situations, a person chooses not the most likely one, but the one that comes to mind first. And since he has little choice, she is unlikely to be suitable.
- Observation. This is a tool with which a person replenishes his internal piggy bank. personal experience. It is on its basis that conclusions are made.
Sometimes you can come across the term "psychological induction", but it does not have a specific definition. Often, by induction we mean the manifestation of certain mental illness or affective state.
Disadvantages of the inductive approach
The use of the inductive method has its limits. The task of logic is to identify them. Drawing an analogy is not a demonstrative method, but it provides an opportunity to search common features objects and phenomena. To obtain a reliable result, it is necessary to have a sufficient number of diverse examples to represent the entire group of phenomena.
Given this, inductive inferences often lead to an erroneous conclusion. The use of induction involves working with a consequence that can be caused for various reasons or a combination thereof. Therefore, the reliability of the information obtained directly depends on the intellectual abilities of the researcher. When forming conclusions, he relies only on his logic and rationalism.
Failure to separate plausible versions leads to an erroneous conclusion. And since human cognitive capabilities are limited, there is always a risk of analysis based on an erroneous sign and obtaining a false result.
What is the difference between deduction and induction?
Deduction in philosophy is a special way of thinking, using which a person draws logical conclusions based on general information and choosing from it the most appropriate development of events for the situation. The use of the deductive method requires the ability to compose logical chains in which one phenomenon consistently follows from the second. This method of processing information became famous thanks to books about Sherlock Holmes, who used it to solve crimes.
The thinkers of the ancient period knew about deduction. Deduction has been used in philosophy to form conclusions based on existing knowledge. Each philosopher had his own idea of correct deduction. For example, Descartes called deduction an intuitive way of obtaining information, which, as a result of lengthy reflection, necessarily leads to the only correct version. Leibniz believed that deduction was the only way to achieve true knowledge.
Deduction is superior to most methods because it performs the following functions:
- helps to quickly find the right solution;
- used in areas of which knowledge is superficial;
- promotes the development of logical thinking;
- helps analyze hypotheses, assessing their plausibility;
- speeds up thinking.
The disadvantages of the deductive method include:
- the inability to apply the method to study new phenomena;
- some special cases are very difficult to bring to a common denominator;
- The knowledge obtained through deduction is more difficult to assimilate, since a person receives a ready-made answer without bothering to collect preliminary information.
The use of deduction in philosophy allows you to quickly and reliably verify information, provided correct use laws of logic.
Application of induction in philosophy
The English encyclopedist and philosopher W. Whewell was J. Mill's main opponent. But he also recognized induction as a necessary and indispensable method of knowledge in philosophy. In the book “Philosophy of Inductive Sciences,” he revised the very essence of scientific knowledge, bringing science out of the realm of the vague and closed into the realm of the accessible and necessary. Thanks to his work, the scientific community was able to conduct research openly. Whewell popularized the word “science” itself, which replaced natural philosophy. The philosopher's rethinking of the theory of induction allowed it to become one of the main research methods.
Researcher K. Popper, in the process of testing hypotheses, assigns key importance to induction. Induction cannot determine whether a statement is true, but it helps accurately select those versions that do not stand up to experimental testing. If, as a result of experiments, some of the theories were confirmed and another part was refuted, those theories that gave a positive result will be preferred. But it should be remembered that induction does not help to find a universal confirmation that will suit all put forward versions.
Analysis and synthesis
Analysis(Greek analysis - decomposition) is a research method, the content of which is a set of techniques and patterns dismemberment(mental or real) subject research into its components. Such parts can be individual material elements of an object or its properties and relationships.
Synthesis(Greek synthesis- connection) is a research method, the content of which is a set of techniques and the law of connecting individual parts of an object into a single whole.
Synthesis - the connection (mental or real) of various elements of an object into a single whole (system) - is inextricably linked with analysis^ (dividing the object into elements).
As can be seen from the definition of these methods, they are opposites, mutually presupposing and complementing each other.
The entire history of knowledge teaches that analysis and synthesis will only be fruitful methods of knowledge when they are used in close unity.
These paired, interrelated research methods occupy a somewhat special position in the system of scientific methods.
Deduction(lat. deductio - deduction) - conclusion according to the rules of logic; a chain of inferences (reasoning), the links of which (statements) are connected by a relation of logical implication. The beginning of deduction is axioms, postulates or simply hypotheses that have the nature of general statements (general), and the end is consequences from premises, theorems (particular). If the premises of a deduction are true, then its consequences are true. Deduction is the main means of proof.
The role of deduction in research is steadily increasing. This is due to the fact that science is increasingly encountering objects that are inaccessible to sensory perception (microworld, universe, past of humanity, etc.).
When cognizing objects of this kind, it is much more often necessary to turn to the power of thought rather than to the power of observation or experiment. Deduction is indispensable in all areas of knowledge where theoretical positions are formed to describe formal, and not real systems(for example, in mathematics).
Deduction differs favorably from other research methods in that, if the initial knowledge is true, it gives true inferential knowledge.
Induction usually means inference from the particular to the general, when, based on knowledge about part of the objects of a certain class, a conclusion is made about the class as a whole.
Induction(lat. inductio- induction) - inference from particular, individual facts to some hypothesis (general statement). A distinction is made between complete induction, when a generalization relates to a finitely observable area of facts, and incomplete induction, when it relates to an infinitely or finitely observable area of facts.
In more in a broad sense words, induction is a method of cognition as a set of cognitive operations, as a result of which the movement of thought from less general provisions to more general provisions. Consequently, the difference is revealed, first of all, in the directly opposite direction of the train of thought.
The immediate basis of inductive inference is the repeatability of the phenomena of reality and their signs. Finding similar features in many objects of a certain class, we draw conclusions that these features are inherent in all objects of this class.
In inductive research, the central place is occupied by inductive inferences. They are divided into the following main groups:
full induction - This is an inference in which a general conclusion about a class of objects is made based on the study of all objects of the class. It produces valid conclusions, which is why complete induction is widely used as evidence;
incomplete induction- this is an inference in which the general conclusion is obtained from premises that do not cover all objects of the class. There are three types of incomplete induction:
A) induction via simple enumeration, or popular induction, represents an inference in which a general conclusion about a class of objects is made on the basis that among the observed facts there is not a single one that contradicts the generalization;
b) induction through selection of facts is not carried out on the basis of the first
facts that come across, but by selecting them from the general mass according to a certain
principle that reduces the likelihood of random coincidences.
For example, if understaffed computers arrived at the warehouse, you can check their entire supply different ways: examine all incoming computers from one batch or selectively examine computers from different batches and different types. It is clear that in the second case the conclusion will be more plausible;
V) scientific induction -- an inference in which a general conclusion about all objects of a class is made on the basis of knowledge of the necessary signs of causal relationships of some of the objects of the class. Scientific induction can-
give not only probable (like the other two types above)
complete induction), but also reliable conclusions.
Establishing the causal relationship of phenomena is a very complex process. However, in the simplest cases, the causal relationship of phenomena can be established using logical techniques called methods of establishing causality, or methods of scientific induction. There are five such methods:
single similarity method - its essence lies in the fact that if two or more cases of the phenomenon being studied have only one circumstance in common, and all other circumstances are different, then this only similar circumstance is the cause of this phenomenon;
single difference method - its essence lies in the fact that if the case in which the phenomenon under study occurs and the case in which it does not occur are similar in everything and differ only in one circumstance, then this circumstance, present in the first case and absent in the second, is the cause of the phenomenon being studied;
combined method of similarities and differences, which is a combination of the first two methods;
concomitant change method- its essence lies in the fact that if the occurrence or change of one phenomenon necessarily causes a certain change in another phenomenon each time, then both of these phenomena are in a causal relationship with each other;
residual method- if a complex phenomenon is caused by a complex cause consisting of a set of certain circumstances, and we know that some of these circumstances are the cause of part of the phenomenon, then the remainder of this phenomenon is caused by the remaining circumstances. Even a brief description of the induction method shows its attractiveness and strength. This strength consists, first of all, in a close connection with facts and practice.
Induction and deduction are closely interconnected and complement each other. Inductive research involves the use general theories, laws, principles, i.e. includes the moment of deduction, and, on the contrary, deduction is impossible without general provisions obtained inductively.