[Boromir88]

Can evil exist without good? Generally, all evil is, is a rebellion against good. Morgoth and Sauron are set up as the 2 primary evils. Why were they the main evils? Because they were the 'satanic rebels' against Eru as Tolkien says:

But in this ’mythology’ all the ’angellic’ powers concerned themselves with world were capable of many degrees of error and failing between the Absolute Satanic Rebellion of Morgoth and his satellite Sauron, and the faineance of some of the other higher powers or ’gods.’~Letter 156

Just a quick question to mull over, with some thoughts to consider before I get into my reply here.

Beanamir, your post definitely was not a lonely one, but I am going to point out the one thing I disagree with:

Tolkien certainly personifies the Ultimate Evil, i.e. evil deeds performed with no end other than the dominion of evil itself, in Morgoth and Sauron. Yet nowhere does he singly personify the Ultimate Good

I agree that there is no 'ultimate good' in the stories, but disagree with the statement there is ultimate evil.

’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.'~Letter 183

Tolkien talks about that even Sauron had 'relics of positive purposes' (his love for order and co-ordination)...and he would go on to say in Letter 183 that Sauron 'represents as near an approach to the wholly evil will as is possible.'

One thing I love about Tolkien's stories is the way he portrays what good and evil is. In Letter 131, he defines evil as 'rebelling against the thoughts of the Creator' and the 'bull-dozing of others free wills.' So, those are 2 clear definition of evil in the story...however, what is not so clear to readers is what makes a person evil and what doesn't? This is the tricky question to answer and Tolkien also hated the criticism that his books were 'all these pure good guys' against 'all these pure bad guys':

Some reviewers have called the whole thing simple-minded, just a plain fight between Good and Evil, with all the good just good, and the bad just bad. Pardonable, perhaps (though at least Boromir has been overlooked) in people in a hurry, and with only fragment to read, and, of course, without the earlier written but unpublished Elvish histories. But the Elves are not wholly good or in the right…In their way the Men of Gondor were similar: a withering people whose only ‘hallows’ were their tombs. But in any case this is a tale about a war, and if war is allowed (at least as a topic and a setting) it is not much good complaining that all the people on one side are against those on the other. Not that I have made even this issue quite so simple: there are Saruman, and Denethor, and Boromir; and there are treacheries and strife even among the Orcs.~Letter dated 25 September 1954

Which sadly seem to reflect Tolkien's thoughts on WW2 in Letter 66:

For we are attempting to conquer Sauron with the Ring. And we shall (it seems) succeed.But the penalty is, as you will know, to breed new Saurons, and slowly turn men and elves into Orcs. Not that in real life things are so clear cut as in a story, and we started out with a great many Orcs on our side...

That is the thing that interests me about Tolkien's books. He defines what is good and what is evil, but as far as what makes somebody good or evil is less clear and up to the reader. As, it's not so simple as 'you do good things you're good and you do evil things your evil.' Intent/motive plays a major role:

Into the ultimate judgement upon Gollum I would not care to enquire. This would be to investigate 'Goddes privitee', as the Medievals said. Gollum was pitiable, but he ended in persistent wickedness, and the fact that this worked good was no credit to him. His marvellous courage and endurance, as great as Frodo and Sam's or greater, being devoted to evil was portentous, but not honourable. I am afraid, whatever our beliefs, we have to face the fact that there are persons who yield to temptation, reject their chances of nobility or salvation, and appear to be 'damnable'. Their 'damnability' is not measurable in the terms of the macrocosm (where it may work good). But we who are all 'in the same boat' must not usurp the Judge.~Letter 181

Simply because good came out of Gollum's actions does not make him a 'good' person. In fact, Tolkien calls him wicked, and showing persisten wickedness. I think motive plays a major part in determining who is truly good and who isn't. Isn't it just so convenient that in a Letter when Tolkien was talking about magic in his stories he comes out and says what is the 'supremely bad motive'?

The supremely bad motive is (for this tale, since it is specially about it) domination of other ’free’ wills.~Letter 155

And I think this is what sets up the Morgoth's and the Sauron's as the prime evils in the story...their intent to dominate, enslave, or simply flat out destroy.

Let me conclude with making a comparison between Radagast and Saruman. Tolkien remarked that both wizards had failed their mission. The Istari's mission was to unite the Free People's of Middle-earth to guide resistance against Sauron. Both Saruman and Radagast fail at this mission, but they fail in different ways, and it's motive that makes Saruman the 'evil' wizard and Radagast a good, yet simply idle one:

Radagast was fond of beasts and birds and found them easier to deal with; he did not become proud and domineering , but neglectful and easygoing, and he had very little to do with Elves or Men although obviously resistance to Sauron had to be sought chiefly in their cooperation. But since he remained of good will (though he had not much courage) , his work in fact helped Gandalf at crucial moments.~From: Tolkien Papers, Bodleian Library found in Hammond and Skulls LOTR Companion

Where Saruman on the other hand no longer resisted and flat out accepted Sauron's goal:

Saruman fell under the domination of Sauron and desired his victory; or no longer opposed it. Denethor remained steadfast in his rejection of Sauron, but was made to believe that his victory was inevitable, and so fell into despair.~Unfinished Tales; The Palantiri

This also just so happens to bring up a little nifty comparison between Denethor and Saruman as well.