[Raynor]

Originally Posted by skip spence

In fact, if we believe what is written in MR, Melkor isn't just a renegade Vala, doing what is evil; he is evil itself, and the rote cause of everything that is wrong with the world . Without his discord during the creation of Arda there wouldn't be any evil deeds whatsoever, and the whole of ME would have remained a blissful paradise, akin to the garden of Eden.

I disagree that Melkor himself introduced evil as a moral category: I would say he was merely its most potent agent. The choice to do good or evil was there, given to him and all the others by their Creator; I would say it is a prerequisite of free will, which all the Valar/Eruhini have. The potential for good and evil actions/thoughts would have existed without Melkor; we could speculate if it would have been better worse without Melkor, but that's fallaciously based on a hypothesis contrary to "reality", so I don't think it could serve us much.

Originally Posted by skip spence

Like I said, in the metaphysics of Arda, Melkor is evil, and when ever someone does what is evil and unnatural, he or she obeys the will of Morgoth.

I disagree; one counter-example is Ungoliant:

Originally Posted by Of the darkening of Valinor, Silmarillion

But she had disowned her Master, desiring to be mistress of her own lust, taking all things to herself to feed her emptiness; and she fled to the south, escaping the assaults of the Valar and the hunters of Oromë

Just like Sauron can't be destroyed completely unless the One ring is destroyed, the marring of Morgoth can't be wholly undone unless Arda itself is destroyed.

In the Atrabeth, it is presumed by Finrod that Eru himself will enter and heal Ea - without destroying it.

Finrod, however, sees now that, as things were, no created thing or being in Arda, or in all Ea, was powerful enough to counteract or heal Evil: that is to subdue Melkor (in his present person, reduced though that was) and the Evil that he had dissipated and sent out from himself into the very structure of the world. Only Eru himself could do this. Therefore, since it was unthinkable that Eru would abandon the world to the ultimate triumph and domination of Melkor (which could mean its ruin and reduction to chaos), Eru Himself must at some time come to oppose Melkor.