The ends justify the means
Meaning
Any actions are acceptable if the final result is good.
Usage
Used when discussing ethics of questionable decisions.
Origin & History
Origins and dates here are approximate summaries. Many idioms have disputed or unknown origins, and not every date has been checked against a historical dictionary, so treat specific dates and stories as a starting point rather than a citation.
Philosophers from Machiavelli to modern writers debated the idea.
Philosophical treatises since the Renaissance cite variations of the idea.