There is a notion that evil may be the absence of good rather than an entity in and of itself. Just as darkness is the absence of light. There is also a notion that evil is the exaggeration of good or good gone bad. When pleasure turns to pain, when love turns to lust, when care turns to constraint, when hope is replaced by hippocracy, when faith becomes fallibility, and when charity becomes chastisement.
This makes some sense to me because I don't think duality is a stable environment. Either one wins or the other. If singularity is the norm then it is possible for extremes to be expected but never with the possibility of total destruction. Opposition in all things is achievable but not at the risk of defeat. Enlightenment is achieved but only through exertion.