Questions: Modal Realism

Question 1

Lewis says 'actual' is an indexical term. What does this mean for his view?

Model answer: An indexical is a term whose reference shifts with context of utterance — 'here' refers to wherever the speaker is, 'I' refers to whoever is speaking, 'now' refers to the time of utterance. Lewis claims 'actual' works the same way: it refers to whichever world the speaker inhabits. For us, that's our world. For inhabitants of other possible worlds, 'actual' refers to *their* world. No world is intrinsically actual or metaphysically privileged — 'actual' just means 'the one I'm in.'

This is central to Lewis's view because it blocks the objection that modal realism must assign special status to the actual world. If 'actual' is indexical, there's no metaphysically distinguished world that all the other worlds are 'merely possible' relative to — all worlds are on equal ontological footing. The asymmetry is epistemological (we know our world from the inside) not metaphysical.

Question 2

Ersatzists and modal realists disagree about whether possible worlds are useful for analyzing modality.

• T. True
• F. False

Answer: False

Both ersatzists and modal realists accept the possible-worlds framework and its semantic applications. Their dispute is about the *nature* of possible worlds — concrete (Lewis) vs. abstract (ersatzists). The question is metaphysical, not about the utility of the framework. Lewis himself invented much of the formal apparatus that both camps use.