Full Idea
On my conception, the notions of metaphysical necessity and possibility are not defined or analyzed in terms of the apparatus of possible worlds. The order of analysis is just the reverse: possible worlds rely on the notion of what might have been.
Gist of Idea
Possible worlds rely on what might have been, so they can' be used to define or analyse modality
Source
Nathan Salmon (The Logic of What Might Have Been [1989], IV)
Book Reference
Salmon,Nathan: 'Metaphysics, Mathematics and Meaning' [OUP 2005], p.139
A Reaction
This view seems to be becoming the new orthodoxy, and I certainly agree with it. I have no idea how you can begin to talk about possible worlds if you don't already have some idea of what 'possible' means.