Is Evil Necessary?
Martin Luther allowed that there are cases where a little evil is a positive good. He wrote, "Seek out the society of your boon companions, drink, play, talk bawdy, and amuse yourself. One must sometimes commit a sin out of hate and contempt for the Devil, so as not to give him the chance to make one scrupulous over mere nothings... ."
In certain schools of political philosophy, leaders are encouraged to be indifferent to good or evil, taking actions based solely on practicality; this approach to politics was put forth by Niccolò Machiavelli, a 16th-century Florentine writer who advised politicians "...it is far safer to be feared than loved."
The international relations theories of realism and neorealism, sometimes called realpolitik advise politicians to explicitly disavow absolute moral and ethical considerations in international politics in favor of a focus on self-interest, political survival, and power politics, which they hold to be more accurate in explaining a world they view as explicitly amoral and dangerous. Political realists usually justify their perspectives by laying claim to a "higher moral duty" specific to political leaders, under which the greatest evil is seen to be the failure of the state to protect itself and its citizens. Machiavelli wrote: "...there will be traits considered good that, if followed, will lead to ruin, while other traits, considered vices which if practiced achieve security and well being for the Prince."
Anton LaVey, founder of the Church of Satan, was a materialist who asserted that evil is actually good. He was responding to the common practice of describing sexuality or disbelief as evil, and his claim was that when the word "evil" is used to describe the natural pleasures and instincts of men and women, or the skepticism of an inquiring mind, the things called evil are really good.
Read more about this topic: Evil, Philosophical Questions About Evil