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18 terms

Important terms for critical thinking and logic.

Categorical Proposition

A proposition that relates two classes or categories. Categorical propositions differ from a

proposition in that they are not comprised of sentences that are either true or false.

proposition in that they are not comprised of sentences that are either true or false.

Categorical Syllogism

A syllogism in which all three statements are categorical claims/propositions. A deductive argument consisting of three statements in categorical form that together use only three terms, called the major, minor, and middle

Categories

Quality and quantity are attributes of the categorical proposition.

Quality

Is either affirmative or negative.

Quantity

Is either universal or particular.

Classes

Refers to the subject term and the predicate term. The subject is the noun. The predicate describes the

subject.

subject.

Copula

Links the subject with the predicate.

Deductive Argument

An argument in which the conclusion follows necessarily or directly from the premises.

Fallacies

A defect in an argument arising from some source other than the merely false premises. Both

Inductive and deductive arguments are susceptible to fallacies.

Inductive and deductive arguments are susceptible to fallacies.

Inductive Argument

An argument in which the conclusion follows merely probably from the premises.

Predicate Term

Something that is affirmed or denied concerning an argument of a proposition.

Proposition

The information or content of a statement. The meaning of a statement. A sentence that is

either true or false.

either true or false.

Quantifier

"all", "no" or "some" are quantifiers. They specify how much of the subject class is included or

excluded from the predicate class. Determines the quality of a universal proposition.

excluded from the predicate class. Determines the quality of a universal proposition.

Subject Term

The part of a proposition about which a statement is made.

Syllogism

A deductive argument that consists of two premises and one conclusion.

Syllogistic Logic

Logic dealing with categorical propositions and categorical syllogisms

Soundness

The argument is valid the premises are actually true.

Validity

An argument in which the premises provide sufficient support for drawing the conclusion. This

has to do with the relationship between the premises and the conclusion. It is about a truth

value relationship between the premises and the conclusion. It's all about the logical

construction of the argument.

has to do with the relationship between the premises and the conclusion. It is about a truth

value relationship between the premises and the conclusion. It's all about the logical

construction of the argument.