The basic laws of logic

In logic, its laws. The main of them are four. Three of them were formed by Aristotle. The laws of Aristotle's logic are the law of non-contradiction, of the excluded third, of identity. Much later, one more law was added to the basic laws - a law of sufficient cause.

The laws of propositional logic have a direct relation to absolutely all reasoning. The logical form, as well as the operation performed by this reasoning, has no significance at all.

There are additional laws of logic. They include:

• twice no;
• Contraposition.

Various laws are also being built on these laws. They provide a connection of thoughts.

Laws of Logic

The first law is law of identity. The bottom line is that in any thought in the processreasoning, there must be some clear, inner content. It is also important that this content does not change in the process. Certainty in some sense is a fundamental property of thinking. On its basis, the law of identity is derived: all thoughts must be wholly identical with themselves. Different thoughts can not be identified under any circumstances. Often, this law is violated by the fact that the same thoughts are expressed in different ways. Also, problems arise when a word is used that has several very different meanings. In this case, thoughts can be identified wrongly.

Identification of incompatible thoughts oftenoccurs when the dialogue is conducted by people of different professions, differing from each other in the level of education and so on. Identification of different concepts is a serious logical error, which in some cases people admit intentionally.

The laws of logic include law of non-contradiction. To begin with, logical thinking isthinking is consistent. Any contradictory thought can significantly hinder the process of cognition. Formal-logical analysis is based on the necessity of non-contradictory thinking: if there are two contradictory concepts, then at least one of them must be false. At the same time, they can not be true under any circumstances. This law can only act on two absolutely contradictory judgments.

The law of the excluded third is also included in the basic laws of logic. Its effect extends to conflicting judgments. The bottom line is that two opposing judgments are not false at the same time - one is necessarily true. Let us note that contradictory propositions call such statements, one of which denies anything about the subject or the phenomenon of our world, and the second at the same moment maintains the same thing about the same phenomenon or object. In some cases, it may not be quite a phenomenon or an object, but only about some specific part. In the event that it is possible to prove the truth of one of the contradictory judgments, the falsity of the other is proved automatically.

Completes the laws of logic law of good reason. He expresses those demands thatare presented to the validity of thoughts. The bottom line is that any reason that has a sufficient basis can be recognized as true. In other words, if there is an idea, then there must be its justification. In most cases, a person's experience is a sufficient basis. In some cases, it is possible to prove the truth only by providing facts, additional information gathering and so on. To confirm any particular cases, one does not need to resort to any experience to confirm the truth - in the world there are many axioms, that is, that which does not need any proof.