A simple categorical syllogism and examples of its use in judicial practice

Logic, as is known, consists of statements and inferences. One of its main bricks is a categorical syllogism - it is a deduction, built deductively, that is, a conclusion is drawn about a private situation from a common one. It is formed on the basis of two main arguments, or parcels, connected by a common term. Since there are only two such arguments, the syllogism is called simple, and because the premises are asserted (or denied) very categorically, such a simple statement is called categorical. Here is the simplest example of such a conclusion. The first argument: "All people are mortal." The second argument: "Ivan is a man". Conclusion, the same judgment, therefore, sounds: "Ivan is mortal". As we see, the correctness or error of all parcels is not considered here. We accept as a reality and the fact that human life ever ends, so does Ivan's belonging to the human race.

On the example of this simple deduction, one can see that a simple categorical syllogism has its own structure. In every logical deduction, a predicate (a word with some indefinite meaning, in our case - mortal beings) is always broader than the subject (Ivan). Therefore the premise containing the predicate is called large, and the one containing the subject is small. It connects these arguments with the term intermediary M (medium) - in our case it's people, people. Therefore, in judicial practice, the analysis of logical reasoning must begin with finding out the place in it of the predicate and the subject, and also the presence of an intermediary between them.

In this analysis, it should be borne in mind that a simple categorical syllogism must contain an axiom that is not expressed, but is present: everything that is asserted or denied with respect to the whole kind of objects extends to each subject of this species. Therefore, the following sentence is erroneous: 1. Men become fathers. 2. Peter is a man. 3. Peter is the father. In this example, the axiom of syllogism is not respected, since paternity does not apply to all men. Therefore, when constructing conclusions, you must strictly adhere to the rules. There are only seven of them: three of them concern terms, and four - parcels.

Rule one: a simple categorical syllogism contains only three terms. Every fourth term is superfluous. Identification of different concepts leads to error. For example: 1. Sidorov committed theft. 2. Sidorov - the noun. 3. The noun made a steal. Here Sidorov and the noun have different meanings. Rule two: the term-mediator should be present in the premises. If the relationship between the predicate and the subject can not be established or is unproven, then the syllogism remains shaky: 1. Some people are murderers. 2. Ivan can be called a certain person. 3. Ivan is a murderer. And, finally, the third rule. If the term predicate is not used, but it is present in the conclusion, it will be an incorrect syllogism. Examples of this error can be expressed as follows: 1. Murders occur in Moscow and the region. 2. St. Petersburg is not located in the Moscow region. 3. There are no murders in St. Petersburg.

In addition to the rules of terms, the rules of the parcels should be observed. At least one of them must carry a statement in itself, because in order to confirm something, we must start from something. If one of the arguments put forward is a negation, then the conclusion must be a negative. Also, in order for a simple categorical syllogism to turn out to be correct, at least one of the arguments put forward should be of a general character of categorical judgment. And the last rule of the parcels: if at least one of them is private, then the conclusion should be of a private nature. For example: 1. Crime should be punished (general judgment). 2. Ivanov committed a crime (a specific case). 3. Ivanov must be punished.