contrapositive
English[edit]
Etymology[edit]
Noun[edit]
contrapositive (plural contrapositives)
 (logic) The inverse of the converse of a given proposition.
Usage notes[edit]
 From a proposition, its inverse, its converse, and its contrapositive are derived as follows:
 Proposition: "If P then Q."
 Inverse: "If not P then not Q."
 Converse: "If Q then P."
 Contrapositive: "If not Q then not P."
 If a proposition is true then its contrapositive is, too. Thus, if the statement "If I'm Roman, then I can speak Latin" is true, then it logically follows that the statement "If I can't speak Latin, then I'm not Roman" must also be true.
See also[edit]
Translations[edit]
the inverse of the converse of a given proposition
