I am beginning to warm up to the fact that Desmond may be a time traveller. It gives us yet another angle to the philosophy going on - we've got Locke, the skeptical believer, Eko, the priest, and Desmond... The prophet.
Yeah, I really like this assessment! Execept, after the vision in the sweat lodge, it feels like Locke is no longer merely the "skeptical believer" -- he's now a full-on Shaman. So we now have a broader range of spiritual roles being played out on the show.
But here's where things get interesting...
If we have characters on the 'good' side, the Losties, occupying those roles, do they have opposite numbers among the 'bad' side, The Others?
See, we often have the idea of evil as being represented by a single, shizo Adversary, with multiple sides to its personality (see, for example, the otherwise excellent
Fables); but historically, "evil" took on various forms:
The Devil (associated with Challenging or Tempting the good ones, but as a way of testing them, as oppposed to outright corrupting them),
Satan/"The King of Babylon" (who is meant to be evil personified, and thus 'naturally' opposed to the good ones), and
Death/Despair (representing the inevitable entropy of natural goodness; everything ends).
Maybe we ought to keep that in mind, as the roles of specific Others and/or DHARMA employees become more clearly defined.