'Evil be thou may good'. I see no reason why someone should not recognise evil and pursue it as such. Where's the logical or psychological impossibility? If intentional actions are done under a 'desirability characterization' (Anscombe) then I can regard an action as desirable precisely because it is evil.
Evil is not excess harm in the pursuit of an end. Harm is the end: the pleasure in inflicting harm, the pleasure of watching another suffer, the pleasure
in possessing the power to inflict this
harm on another, rather than suffer it
This concept of evil is expressed
perfectly by Milton's Satan in Paradise
Lost when he says "Evil be thou my
Good" (IV, 105-110). Satan would take revenge on God because
He is good, because His rule was mild and loving (IV, 43). Satan
does not just envy God's power; he envies His goodness. Evil is an
attack on the good precisely because it is good and not me or mine.
It is this that Milton's Satan cannot stand...
(C. Fred Alford, 'Evil Be Thou My Good', The Good Society, Vol. 15, No. 2 (2006), pp. 13-16: 15.)
But it's only a poem, someone might say. However, the state of mind which
Satan embodies here can and does have real life replications.
In his Confessions Augustine says:
A murder is committed. Why? To get another's wife or wealth,
or to get the necessities of life. Or for fear another would
deprive the murderer of such things. Or from a sense of wrong
burning for redress. Who murders with no cause but to enjoy
the mere murdering? Who would credit such a motive?
'Who murders with no cause but to enjoy the mere murdering? Who would credit such a motive?' I would. It is a perfectly straightforward conceptual possibility. If the motive is rare, let's hope it stays that way.
I see, by the way, no connexion with weakness of will. One can murder with no cause but to enjoy the mere murdering and do so with clear and firm determination in the face of no countervailing considerations and no regrets.
C. Fred Alford, 'Evil Be Thou My Good', The Good Society, Vol. 15, No. 2 (2006), pp. 13-16: 15-16.