Servant or Master?

[Kuruharan]

Or myth and story mean the same thing, it's just that Tolkien felt like interchanging the two words.

Ahhh...Balrog wings, run away!!!!!!

I'm mostly pondering over the seeming contradiction of Tolkien's words:

In my story I do not deal in Absolute Evil. I do not think there is such a thing, since that is Zero. I do not think that at any rate any 'rational being' is wholly evil.

and

The supremely bad motive is (for this tale, since it is specially about it) domination of other ’free’ wills

Given the fact that Tolkien stated that Melkor came to desire the annihilation of everything (possibly ultimately including himself)...who's to say if Melkor really answered to the description of being a 'rational being' anymore?

Perhaps we feel a greater affinity for Sauron because Sauron's motives are something that is understandable to most of us, while Melkor's goals seem a bit unreal to our minds.