Logic has its own 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, excluded third, identity. Much later, another law was added to the basic laws - the law of sufficient reason.
The laws of propositional logic are directly related to absolutely all reasoning. The logical form, as well as the operation performed by these arguments, has no meaning at all.
There are additional laws of logic. These include:
- twice no;
- counterposition.
Various laws of thought are also based on these laws. 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 must be some clear, internal content. It is also important that this content does not change in the process. Certainty, in a sense, is a fundamental property of thinking. On its basis, the law of identity is deduced: all thoughts should be completely and completely identical to themselves. Different thoughts cannot be identified under any circumstances. Often this law is violated by the fact that the same thoughts are expressed in different ways. Problems also arise in cases where words are used that have several completely dissimilar meanings. In this case, thoughts can be identified erroneously.
Identification of incompatible thoughts often occurs when the dialogue is conducted by people of various professions who differ from each other in the level of education and so on. The identification of various concepts is a serious logical mistake that in some cases people make intentionally.
The laws of logic include the law of non-contradiction. To begin with, logical thinking is consistent thinking. Any thought containing a contradiction can significantly complicate the process of cognition. Formal logical analysis is based on the need for consistent thinking: if there are two conflicting concepts, then at least one of them must be false. At the same time, they cannot be true under any circumstances. This law can only act on two completely contradictory opinions.
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 simultaneously false - one is necessarily true. Note that judgments are called contradictory statements, one of which denies anything about the subject or the phenomenon of our world, and the second at the same moment claims the same thing about the same phenomenon or subject. In some cases, it may not be a phenomenon or an object, but only a specific part. If it is possible to prove the truth of one of the conflicting judgments, then the falsity of the other is proved automatically.
Completes the laws of logic a law of sufficient reason. He expresses the requirements for the validity of thoughts. The bottom line is that any reasonably substantiated thought can be recognized as true. In other words, if there is a thought, then there must be its justification. In most cases, a person’s experience is sufficient. In some cases, it is possible to prove the truth only by providing facts, additional collection of information, and so on. To confirm any particular cases to confirm the truth, it is not necessary to turn to any experience - in the world there are many axioms, that is, one that needs no proof.
