Full Idea
I identify propositions with properties that are instantiated only by entire possible worlds. If properties are the sets of their instances, a proposition is a set of possible worlds. A proposition is the property of being a world where it holds.
Gist of Idea
A proposition is the property of being a possible world where it holds true
Source
David Lewis (On the Plurality of Worlds [1986], 1.5)
Book Reference
Lewis,David: 'On the Plurality of Worlds' [Blackwell 2001], p.53
A Reaction
This is so far away from my concept of a proposition (as a truth-evaluable representational mental event) that I struggle to compute it. So the proposition that I am sitting here is the property of 'being the actual world'. Eh?
Related Idea
Idea 15738 Propositions can't have syntactic structure if they are just sets of worlds [Lewis]