Logical laws are the law of thought, the connection of thought in the process of reasoning or proof

The four classical laws of logic are the foundation of human thought. They are based on the natural features of the surrounding world. These principles are unshakable - they can not be broken or circumvented.

The origin of laws

According to the scientific definition, logical laws are laws on which a person's thinking is built. They appeared as a generalization of the vast experience of people's interaction with the surrounding reality. The reality with which a person touches each day is reflected in his consciousness. This process is considered thinking. It occurs not chaotically and randomly, but according to certain laws.

These rules are identified and formulated by logic. As a science, this discipline explains the principle of the human reasoning. Laws are repetitive stable links affecting the functioning, structure and development of thoughts. They are determined by the objective features of the external world. That's why people can not change them at their own discretion, offering their own logical laws. This is their property allows you to clearly define and formulate the basic principles according to which thinking works.

The basis of thinking

All logical laws are an indisputable axiom, a truth that does not need proof. They remain an important part of the cognitive process and scientific reasoning. Due to these norms it is possible to determine the truth and falsity of thoughts.

At the same time, logical laws are features that are characteristic only of their narrow sphere of application. That is, they are far from absolute, they can be used only in the thinking process. But it is not necessary to transfer these axioms to the outside world.

Types of laws

The laws of logic are classified. The first group includes those norms that are associated with abstract thinking - judgments, concepts and conclusions. The second type is associated with laws that have universal universal character. They are also called basic. In particular, this is the law of identity in logic, contradiction, the excluded third and sufficient grounds.

Why are they considered basic? Because they work equally in any thought process, they are used in proofs and inferences, and, finally, they have the properties of right thinking: logical consistency, reasonableness, consistency and certainty.

History of the discovery

The first three patterns are the so-called logical laws of Aristotle, formulated by the ancient Greek philosopher in the IV century BC. E. They became the basis for all subsequent development of scientific thought. In the 18th century, Gottfried Leibniz discovered another law - a law of good reason.

Later, many scientists tried to question these norms. Thus, mathematical and symbolic logic appeared, while the four laws described above are relevant only to traditional logic.

Identity

According to the classical classification, the most important is the law of identity. In logic, it is paramount. This principle is that the correct and true thought must remain definite and maintain its own uniqueness throughout the entire argument up to the final conclusion. Without this law, human thinking would lose its main instrument. Acting in its framework, people reason according to the principles inherent in nature in the world around us.

Logic as a science comes from the following rule. All qualities of objects must be certain. This is their property that helps human thinking to isolate and isolate the objects of its thinking from the surrounding reality. Without it, you can not argue using concepts. They fix a stable and general - something that reveals the essence of identity.

Substitution of concepts

Well-known formal-logical laws can not be violated, because in this case a person will argue contradictorily and unnaturally. Non-observance of the principle of identity leads to typical mistakes of thinking. First of all, this is a substitution of concepts. Juggling with thoughts and giving out one after another, you can break the chain of reasoning. In addition, it threatens communication complications with the interlocutor.

This rule is especially important in scientific controversy, where each concept has its own strict and outlined framework. Such disputes do not allow ambiguity. Also in ordinary communication, people can misunderstand each other only because they use concepts in different meanings. This error is often associated with the use of words-homonyms. They can coincide in form, but have different meanings (for example, "gender" is both genus and cover underfoot).

Contradiction

According to theory, the law of contradiction lies in the fact that two opposing statements can not simultaneously correspond to the truth. This principle is of great importance for the entire thought process. It is also important that the law of contradiction expresses the objective properties of surrounding things. Its violation leads to a paradox. If it is not observed, things would lose their properties, they would no longer be themselves.

Mankind has long discovered this feature and just as long learned to use it in its own reasoning. If objects can not both have and do not have their properties, then people also have no right to build their judgments, ignoring the principle of contradiction. It is important to note that this law applies only to mutually exclusive phenomena. In other words, one can not say at the same time about a person that he is industrious and lazy.

If the law of contradiction is violated, one can go to demagogy and prove any false assertion. This liberation alienates thought from objective reality, leads it into the jungle of fictions and assumptions. For many centuries, science has developed only because it exists within the framework of the law of contradiction. If a person leaves these limits, his thinking risks becoming incoherent, unsystematic and chaotic. Such reasoning is not tied to anything, they are at odds with formal logic.

The principle of contradiction implies that one of the opposite judgments is false, but does not indicate which of them is false and which is true. At the same time, it is necessary to use this law, being aware of where the limits of its action end. For example, there will be no contradiction when it comes to the same phenomena with different relationships. As an illustration to this disclaimer, the following situation can be used. Andrew is a swimming champion and at the same time is not a boxing champion. Although we are talking about one rank, there is no contradiction here, since it can refer to a variety of sports disciplines.

Excluded third

According to this law, two contradictory theses can not be either false or true at the same time - one of them is false, the other is true. Third there should not be. This law in many ways echoes the principle of contradiction. It reflects the sequence of human thinking. This law does not allow confusion. If the opposite proposition is true, then the other is false (and vice versa).

At the same time, the law of the excluded middle does not characterize the phenomenon in any way. To check which of them is true, it is possible only in practice. To do this, it is necessary to establish the correspondence or inconsistency of the statement of the surrounding reality. The main significance of this law lies in the fact that the principle indicates a direction for seeking the truth. He emphasizes - the solution lies in the opposite "yes" or "no". The law denies the possibility of a median answer.

Uncertainty of phenomena

The law of the excluded third requires that a person clarify the concepts. This is necessary in order to find answers to an alternative question. At the same time, this law can not be absolutized. It does not reflect the transient qualities of phenomena and therefore is not universal. For example, this principle does not apply when it comes to the clinical death of a person, an unproved hypothesis, a long-term weather forecast.

The fact is that in the situations described above, thinking goes beyond the bounds of classical two-valued logic. To truth and falsehood, uncertainty is added-something in between, containing both. In addition, it is necessary to take into account another feature of surrounding things and phenomena. All of them can be internally contradictory and include opposing features. The law of the excluded middle does not consider the features of the objective world. Much more it is used in theoretical disciplines, for example, in economics and jurisprudence.

Sufficient ground

The last law of thought is the law of sufficient reason. It is built on the most important principle - every true thought must have a solid foundation. As evidence of the correctness of reasoning, facts, laws, rules, regulations, and other arguments that were previously recognized as truthful can be used. In order to remain consistent in his speech, a person must base his conclusions only on a sufficient basis.

This principle exists because of the close interconnection of objects and phenomena existing in the surrounding world. Thanks to her, a person, knowing one fact, can bring out one more. For example, the official language of Brazil is Portuguese, which gives reason to believe that in former times this country was a Portuguese colony.

Causal relationships

All logical laws and rules have well-known examples. The principle of sufficient reason was often used by Conan Doyle in his books about Sherlock Holmes. A fictional detective, conducting his investigations, often turned to cause-and-effect relations. Each of his inferences corresponded to the fulfilled scheme. Holmes restored the cause, building a chain from the logical foundation (that is, the real effect) to the logical consequence (that is, the real reason).

The same method used by doctors. They, like no one, perfectly know and understand the logical laws. Examples of their use can be found in the diagnoses of patients. When explaining the circumstances of the disease, doctors build the relationship between the effect and the cause. At the same time, their conclusions are checked with additional thoroughness. To do this, experts resort to convincing arguments, confirmed by science and practice.

The law of sufficient grounds requires abandoning unreasonable conclusions. He does not allow blurred evidence of the truth of human thought. This law is a convenient tool in skillful hands. With its help you can separate the false from the true and come to the right conclusion. Another feature of this law is its abstract nature, which is based on the relative stability and mutual conditioning of phenomena and objects.