My readings/beliefs about weakness of will have led me to think that "evil for its own sake" is impossible. Yet, some actions seem to be done as such. So I think this difference is important:
(A) I lied (or w/e) for the sake of lying. (B) I lied for the sake of the fact that lying is evil.
On my view, B is what is ruled out. Is this sufficient to reconcile my intuition and abstractions, here?
EDIT: Having just read a new SEP article that directly considers this question of evil for its own sake, I am now motivated to define a third option. (To boot, since the discussion is cashed out in terms of radical evil, which level of evil is entangled with notions such as akrasia and acedia (per Kant's discourse on the inescapable rationality of the moral law), I now have a go-to reference for associating the question of akrasia, with the question of evil for its own sake.) This third option is:
(C) I will lie for the sake of the fact that other people (who I am trying to offend) think that lying is evil.
Why propose (C)? Because in the SEP article, there seem to be authentic examples given of people willing a particular evil thing for the sake of evil in general:
In this context, consider (if you can bear it) Stone 2009’s portraits of the worst serial killers: although some perpetrators report that they take what they are doing to be good—ridding the world of “garbage women”, giving someone his “just deserts”, correctly following the orders of the voices in their head, and so on—others openly admit that what they are doing is bad, wrong, evil, despicable, and so on. In such cases, the perpetrators are not making a series of unsound inferences, or mistaking the bad for the good. Rather, they seem to be engaged in a self-conscious turning away from anything that could be regarded as good by anyone.
So to avoid the strict conclusion of (B), I suggest the possibility of (C), which is close enough to (B) to be "mistaken for it," perhaps.