Much of ontology is made up of absolutists, those who have a notion that things actually exist and are whatever they happen to be, and in the West, that idea is traced back to Plato.
Plato is well-known for his concepts of Forms, unknowable perfect templates for the things that exist around us. In his allegory of the cave, us plebes (I like to mix Greek and Roman concepts. Forgive me), can never know the Forms. Instead we just get to see poor abstractions of them as shadows on the wall.
In the idea of wiki as a medium, there is the question of an artist's language of form. It would not be too much of a stretch to say that the language of form is like the fire, or whatever it is that's illuminating the cave.
To Plato, and the absolutists of course, true knowledge of a Form is impossible. As such _every_ representation is an abstraction. Humans have pretty much always fought over whose abstraction is better than others, but for the medium like oils or wiki it doesn't matter--they exist to serve the artist in their quest for meaning.
But of course, I'm an Aristotelian, so I think this is a whole lot of malarky. But it is fun to think about.