Intermediate Logic Lessons 1-5

Propositional Logic

A branch of formal, deductive logic in which the basic unit of thought is the proposition.

Truth-Functional

when its truth value depends upon the truth values of its component parts.

Simple Proposition

A proposition with only one component part.

Compound Proposition

A proposition with more than one component part.

Logical Operators

Words that combine or modify simple propositions to make compound propositions.

Propositional Constant

An uppercase letter that represents a single, given proposition.

Propositional Variable

A lowercase letter that represents any proposition.

Negation

A logical operator that denies or contradicts a proposition.

Truth Table

A listing of the possible truth values for a set of one or more propositions.

Defining truth table

displays the truth values produced by a logical operator modifying a minimum number of variables.

Conjunction

A logical operator that joins two propositions and is true if and only if both the propositions are true.

Disjunction

A logical operator that joins two propositions and is true if and only if one or both of the propositions are true.

Conditional Operator

Asserts that one component (the antecedent) implies the other (the consequent). It is false if and only if the antecedent is true and the consequent is false.

Biconditional Operator

is true when both component propositions have the same truth value, and is false when their truth values differ.