##  [Modal Realism](/modal-realism-0) 

 Definition

A metaphysical position that treats possible worlds as concrete, fully real entities on the same ontological footing as the actual world; modal statements (about possibility and necessity) are true or false relative to what occurs in these concrete worlds.

 

 

 

 

 

 





## Principle

Principle

Modal truth is grounded in the existence of concrete alternate worlds: a proposition is possible if it is true in at least one such world and necessary if it is true in all of them under this ontology.

 

 

 

 

 





## Demonstration

Demonstration

Illustrative scenario → To evaluate the counterfactual ‘‘If agent A had acted differently, outcome B would have occurred,’’ the modal realist affirms there exists a concrete world where A acts differently and B occurs; the counterfactual’s truth reduces to facts about that world.

 

 

 

 

## Misapplication

Misapplication

Interpreting ‘‘possible world’’ as merely a useful fiction without recognizing that modal realism entails an ontological commitment. The error is failing to track the metaphysical cost of treating possibilities as concrete entities.

 

 

 

 

 





## Consequence

Consequence

Endorses a large ontology of non-actual entities with implications for identity across worlds, modal semantics, and metaphysical parsimony—affecting debates about individuation, causation, and counterfactual analysis.

 

 

 

 

## Reversal

Reversal

Alternative frameworks (e.g., ersatz modal theories, actualist or counterpart accounts) model modality without positing concrete worlds; adopting them avoids the heavy ontological commitment of modal realism while aiming to preserve explanatory power.

 

 

 

 

 





## Boundary

Boundary

Clearly within: ontological claims that treat non-actual worlds as concrete objects with full reality. Boundary case: talk of possible scenarios used heuristically in science without ontological commitment. Clearly outside: purely linguistic or epistemic accounts of possibility that deny non-actual concreteness.

 

 

 

 

 





## Semantic Tension

Semantic Tension

Ontological parsimony ↔ Explanatory scope: modal realism trades parsimony for a straightforward semantics of modality; rival accounts trade ontology for more economical metaphysics.

 

 

 

 

 





## Synthesis

Synthesis

Modal realism makes modal discourse ontologically literal: it explains possibility by positing concrete alternatives, clarifying modal semantics at the cost of a sprawling ontology that alternative accounts aim to avoid.