Actuality, Possibility, and Worlds

This monograph presents a comprehensive philosophical defense of actualism about possible worlds, while developing a novel account that integrates modal metaphysics with theistic philosophy. Pruss argues that possible worlds should be understood as maximal possible states of affairs rather than concrete universes or abstract objects existing independently of God. His central thesis maintains that all possibilities are grounded in divine attributes and activities, positioning God as the ultimate foundation of modal reality.

The work engages critically with David Lewis's modal realism, which treats possible worlds as concrete physical universes, and challenges various forms of abstractionist accounts that view possible worlds as ungrounded abstract entities. Pruss develops a sophisticated actualist theory where possible worlds are maximal states of affairs that exist as divine ideas or thoughts. This approach avoids the ontological extravagance of modal realism while providing robust truthmakers for modal claims.

Pruss employs rigorous analytical methodology, drawing on contemporary developments in modal logic, metaphysics, and philosophy of language. He addresses fundamental questions about the nature of properties, propositions, and states of affairs, arguing that these entities can be understood within an actualist framework without sacrificing explanatory power. The work demonstrates how theistic actualism can resolve longstanding puzzles in modal metaphysics, including the problem of contingent existents and the grounding of alien possibilities.

A distinctive contribution emerges in Pruss's treatment of divine simplicity and necessity. He argues that God's necessary existence provides the metaphysical foundation for all modal truths, while maintaining that God freely creates contingent beings. This synthesis addresses tensions between classical theism and contemporary modal metaphysics, showing how divine aseity remains compatible with genuine contingency in creation.

The monograph advances debates about grounding and fundamentality by proposing that all possibilities ultimately depend on God's nature and will. Pruss defends this view against objections concerning bootstrapping and circular explanation, demonstrating how theistic actualism offers explanatory advantages over both naturalistic and platonistic alternatives. His account provides a unified treatment of modality that connects metaphysical possibility with divine omnipotence and perfect knowledge.

This work makes significant contributions to both analytic philosophy of religion and modal metaphysics, offering a sophisticated defense of how God grounds the entire modal realm while preserving genuine contingency and creaturely freedom.