# Appendix:Glossary of logic

This is a glossary of logic.

**Table of Contents:** A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

## A[edit]

- antecedent
- The conditional part of a hypothetical proposition

## C[edit]

- conclusion
- In a syllogism, the proposition that follows as a necessary consequence of the premises.

- consequent
- The second half of a hypothetical proposition; Q, if the form of the proposition is "If P, then Q."

- contraposition
- The statement of the form "if not Q then not P", given the statement "if P then Q".

## D[edit]

- domain of discourse
- In predicate logic, an indication of the relevant set of entities that are being dealt with by quantifiers.

## F[edit]

- formula
- A syntactic expression of a proposition, built up from quantifiers, logical connectives, variables, relation and operation symbols, and, depending on the type of logic, possibly other operators such as modal, temporal, deontic or epistemic ones.

## I[edit]

- implication
- The connective in propositional calculus that, when joining two predicates A and B in that order, has the meaning "if A is true, then B is true".

- inference
- The act or process of inferring; the production of a proposition based on given propositions.

- inverse
- A statement constructed from the negatives of the premise and conclusion of some other statement: ~p → ~q is the inverse of p → q.

## M[edit]

- material implication
- An implication as defined in classical propositional logic, leading to the truth of paradoxes of implication such as Q --> (P --> P), to be read as "any proposition whatsoever is a sufficient condition for a true proposition".

- modus ponens
- A valid form of argument in which the antecedent of a conditional proposition is affirmed, thereby entailing the affirmation of the consequent.

## P[edit]

- premise
- Either of the first two propositions of a syllogism, from which the conclusion is deduced.

- proposition
- The content of an assertion that may be taken as being true or false and is considered abstractly without reference to the linguistic sentence that constitutes the assertion.

## R[edit]

- reductio ad absurdum
- The method of proving a statement by assuming the statement is false and, with that assumption, arriving at a blatant contradiction.

## S[edit]

- sentence
- A formula with no free variables.

- syllogism
- An inference in which one proposition (the conclusion) follows necessarily from two other propositions, known as the premises.