Full Idea
The possible worlds framework that Kripke introduces should be understood not as a metaphysical theory, but as a methodological framework.
Gist of Idea
Kripke's possible worlds are methodological, not metaphysical
Source
Robert C. Stalnaker (Reference and Necessity [1997], Intro)
Book Reference
Stalnaker,Robert C.: 'Ways a World Might Be' [OUP 2003], p.166
A Reaction
That's certainly how I see possible worlds. I lose no sleep over whether they exist. I just take a set of possible worlds to be like cells in a spreadsheet, or records in a database.