Full Idea
The domains in Plantinga's interpretation of Kripke's semantics are sets of essences, and the values of variables are essences. The values of predicates have to be functions from possible worlds to essences.
Gist of Idea
Plantinga has domains of sets of essences, variables denoting essences, and predicates as functions
Source
report of Alvin Plantinga (Actualism and Possible Worlds [1976]) by Robert C. Stalnaker - Mere Possibilities 4.4
Book Reference
Stalnaker,Robert C.: 'Mere Possibilities' [Princeton 2012], p.117
A Reaction
I begin to think this is quite nice, as long as one doesn't take the commitment to the essences too seriously. For 'essence' read 'minimal identity'? But I take essences to be more than minimal, so use identities (which Kripke does?).
Related Ideas
Idea 16463 Adams says actual things have haecceities, but not things that only might exist [Adams,RM, by Stalnaker]
Idea 16470 Plantinga's essences have their own properties - so will have essences, giving a hierarchy [Stalnaker on Plantinga]