Evil exists like holes in Swiss cheese

Evil exists in the cosmos like holes in a Swiss cheese: the holes are there, but they are only as noncheese and have no existence apart from the cheese. As one cannot eat a cheese and discard the holes into a box, one cannot remove good and put evil into another category. Evil is merely the absence of good.
Jeffrey Burton Russell, The Devil: Perceptions of Evil from Antiquity to Primitive Christianity (Ithaca, N.Y: Cornell University Press, 1993), 205.