Judgments in logic. What is judgment, types of judgments

Judgment is a form of thinking that affirms or denies anything about the existence of objects, the connections between them and their properties, as well as the relationships between objects.

Examples of judgments: "The Volga flows into the Caspian Sea", "A. Pushkin wrote the poem "The Bronze Horseman", "The Ussuri Tiger is listed in the Red Book", etc.

Structure of judgments

Judgment includes the following elements: subject, predicate, bundle and quantifier.

1. The subject (Latin subjektum - "underlying") is what is said in this judgment, its subject ("S").
2. The predicate (Latin praedicatum - "spoken") is a reflection of the feature of the subject, what is said about the subject of judgment ("R").
3. A bunch is an attitude, between the subject ("S") and the predicate ("P"). Determines the presence / absence of a subject of any property expressed in the predicate. Can both be implied and denoted by the sign "dash" or the words "is" ("is not"), "there", "is", "essence", etc.
4. The quantifier (quantifier word) determines the scope of the concept to which the subject of judgment relates. It is in front of the subject, but it can also be absent in judgment. Denoted by such words as "all", "many", "some", "none", "nobody", etc.

True and false judgments

Judgment is true in the case when the presence of attributes, properties and relations of objects asserted / denied in judgment is true. For example: "All the swallows are birds", "9 more than 2", etc.

If the statement contained in the judgment is untrue, we are dealing with a false judgment: "The sun revolves around the Earth," "The kilogram of iron is heavier than a kilogram of cotton wool," etc. The right judgments form the basis of right conclusions.

However, in addition to the two-valued logic, in which judgment can be either true or false, there is also multidimensional logic. According to its conditions, the judgment can also be uncertain. This is especially true of future individual judgments: "Tomorrow there will be / no sea battle" (Aristotle, "On Interpretation"). If we assume that this is a true proposition, then the sea battle tomorrow can not but happen. Therefore, it is necessary that it happens. Or vice versa: arguing that this judgment is false at the moment, we thereby make necessary the impossibility of tomorrow's sea battle.

Judgments by the type of utterance

As is known, according to the type of utterance, three types of sentences are singled out : narrative, motivational and interrogative. For example, the sentence "I remember a wonderful moment" refers to a narrative type. It is advisable to suggest that such a judgment will also be narrative. It contains certain information, reports on a certain event.

In turn, the interrogative sentence contains a question that implies the answer: "What does the future prepare for me?" Moreover, it does not state anything and does not deny anything. Accordingly, the statement that such a judgment is interrogative is erroneous. The interrogative sentence does not in principle contain a judgment, because the question can not be differentiated according to the principle of truth / falsity.

An incentive type of sentences is formed when there is a certain motivation for action, a request or a ban: "Arise, prophet, and see and hear." As for judgments, according to some researchers, they are not contained in proposals of this type. Others believe that this is a variety of modal judgments.

Judgment quality

From the point of view of quality, judgments can be either affirmative (S is P) or negative (S is not P). In the case of an affirmative proposition, a predicate is given a certain property (-a) to the subject. For example: "Leonardo da Vinci is an Italian painter, architect, sculptor, scientist, naturalist, inventor and writer, the greatest representative of Renaissance art."

In negative judgment, on the contrary, the property of the subject is taken away: "The theory of the 25th frame of James Weikeri has no experimental confirmation."

Quantitative characteristic

Judgments in logic can have a general character (relating to all subjects of this class), private (to some of them) and single (when it comes to an object that exists in a single instance). For example, it can be argued that such a judgment as "At night, all cats of sulfur" will refer to a common species, since it affects all representatives of the feline (subject of judgment). The statement "Some snakes are not poisonous" is an example of a particular judgment. In turn, the statement "Wonderful Dnipro in quiet weather" is a single one, since it is a question of one particular river, existing in a single form.

Simple and complex judgments

Depending on the structure, the judgment can be of the simple or complex type. The structure of a simple proposition includes two related concepts (SP): "The book is the source of knowledge". There are also judgments with one concept - when the second is only implied: "It was getting dark" (P).

A complex form is formed by combining several simple judgments.

Classification of simple judgments

Simple judgments in logic can be of the following types: attributive, judgments with relations, existential, modal.

Attributive (judgments-properties) are aimed at affirming / denying the existence of certain attributes (attributes), types of activity. These judgments have a categorical form and are not questioned: "The nervous system of mammals consists of the brain, the spinal cord and the departing nervous pathways."

In judgments with relations, certain relations between objects are considered. They can have a spatio-temporal context, a cause-effect, etc. For example: "An old friend is better than the new two", "Hydrogen is easier than carbon dioxide 22 times".

Existential judgment is a statement of the existence / non-existence of an object (both material and ideal): "There is no prophet in his own country", "The moon is a companion of the Earth".

Modal judgment is a form of assertion in which a certain modal operator is present (necessary, good / bad, proven, known / unknown, forbidden, believe, etc.). For example:

• "In Russia, an educational reform is necessary" (an aletic modality is an opportunity, a necessity for something).
• "Everyone has the right to personal inviolability" (deontic modality - moral norms of social behavior).
• "Negligent attitude to state property leads to its loss" (axiological modality - relation to material and spiritual values).
• "We believe in your innocence" (epistemic modality - the degree of reliability of knowledge).

Complex judgments and types of logical connectives

As already noted, complex judgments consist of several simple ones. As logical connectives between them are such techniques as:

• Conjunction (a ʌ b - connecting judgments). Judgments-conjuncts have a bunch of "and": "The exercise of the rights and freedoms of man and citizen should not violate the rights and freedoms of others."
• Disjunction (avb - separative judgments). As compound elements, sentences-disjuncts are used, as a bundle - the union "or". For example: "The plaintiff has the right to increase or decrease the amount of claims."
• The implication (a → b - the judgment-consequence). If the structure of a complex proposition distinguishes between the premise and the effect, then it can be argued that such a judgment is implicit. As a bundle in this form, such unions as "if ... that" are used. For example: "If you pass an electric current through a conductor, then the conductor heats up," "If you want to be happy, be him."
• Equivalence (a ≡ b - identity judgments). It occurs when the values of a and b are the same (or both are true or both are false): "Man is created for happiness, like a bird for flight".
• Negation (¬a, ā - judgment-inversion). To every initial assertion a composite assertion, which denies the original assertion, is put in correspondence. It is carried out by means of a ligament "not". Accordingly, if the original statement looks like this: "The bull reacts to the red light" (a) - then the negation will sound like: "The bull does NOT respond to the red light" (¬a).