“I am part of that power which eternally wills evil and eternally works good.”
—Mephistopheles (In Faust I by Joann Wolfgang von Goethe)
We all know the cliche that the road to hell is paved with good intentions. For some reason, no one ever seems to consider the inverse proposition. Perhaps people prefer to focus on positive results when such are presented instead of fishing for less-than-admirable motives.
Then again, no one ever exclaims “but I meant badly!” when praised.
Today, you are being challenged to consider a situation in which detestable motives lead to ethically admirable results. However, your post should transcend mere description; you should also cast some sort of judgment on the person or actions. Your exposition may also need to consider the nature of “good” and “bad” within the context of your example; conversely, you may choose to defend the concept of objectively correct ethical stances against relativist positions.
No matter how deeply philosophical you choose to become, be sure to select an example for which there is no obvious answer. Also, don’t lapse into an emotionally charged sympathy for the devil.