The end justifies the means
The end justifies the means is a paraphrase of Niccolò Machiavelli. It means that if a goal is morally important enough, any method of getting it is acceptable. The idea is ancient, but it was not meant to justify unnecessary cruelty. It was part of a political philosophy called consequentialism. The basic idea is that a policy can be judged by its outcome. All modern versions of consequentialism have to deal with the limitations necessary to prevent tyrants abusing this idea.[1]
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