Practice question · Sort into groups
Sort each position by its account of what possible worlds are.
Groups: Modal realism · Ersatzism
- Worlds are concrete, as real as the actual world
- Worlds are abstract objects such as maximal consistent sets of sentences
- Only one concrete universe exists
- "Actual" is indexical, meaning simply "this world"
Hints
- One view multiplies concrete universes; the other keeps just one and makes the rest abstract.
- The indexical treatment of "actual" is distinctive of the concrete view.
Show the answer
Modal realism: Worlds are concrete, as real as the actual world, "Actual" is indexical, meaning simply "this world"
Ersatzism: Worlds are abstract objects such as maximal consistent sets of sentences, Only one concrete universe exists
Why
Lewis’s realism takes the semantics at face value and pays in ontology; ersatzism keeps one concrete universe and makes the alternatives abstract. Both preserve the formal semantics, they disagree about what it commits you to.
Practise Modal Systems and Possible Worlds
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More questions on Modal Systems and Possible Worlds
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