The End Justifies The Means Definition

Morally wrong actions are sometimes necessary to achieve morally right outcomes; actions can be considered morally right or wrong only by virtue of the morality of the outcome.

Wiktionary

Origin of The End Justifies The Means

Widely attributed to Machiavelli 's The Prince , which does reflect this philosophy but does not use the phrase in this wording. A possible source is Ovid 's Heroides (ca. 10 BC), which says exitus acta probat (“the outcome justifies the deeds").

From Wiktionary