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 are directly related 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.

On these laws, various kinds of reflections are also constructed. They provide a connection of thoughts.

Laws of Logic

The first law is the law of identity . The bottom line is that in any thought in the process of reasoning there should 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 words that have several completely different meanings are used. In this case, thoughts can be identified wrongly.

The identification of incompatible thoughts often occurs when people of different professions are engaged in a dialogue that differ in their 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 the law of non-contradiction . To begin with, logical thinking is a consistent one. Any contradictory thought can significantly hinder the process of cognition. Formally 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 also enters into the basic laws of logic. Its action 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 something about the object or the phenomenon of our world, while 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.

The law of sufficient reason completes the laws of logic. He expresses the demands that are made on the validity of his 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 a justification for it. 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 to confirm the truth, it is not necessary to refer to any experience - there are a lot of axioms in the world, that is, that which does not need any proof.