Disjunction

Disjunction

disjunctive proposition

a proposition with the form p or q. The p and q are called disjuncts

Example : My teacher is in her classroom or in her office

a disjunctive proposition is true if one of the disjuncts is true

The “or” is inclusive if both disjuncts are true, then the entire disjunction can still be true

if the context makes it clear that a disjunctive proposition is using the exclusive “or”, then the entire proposition is true if and only if one disjunct is true

disjunctive syllogism

a syllogism which uses a disjunction as one premise

valid form of disjunction syllogism ( p or q / not -p/ therefore not-q