Persistenslogik

Persistenslogik is a field at the intersection of formal logic, philosophy of time, and ontology that studies how objects and their properties endure through time. It seeks to formalize the notion of persistence—how an entity remains the same through successive states or moments—and to model the conditions under which identity across time holds. The topic often engages with the debate between endurantism, the view that objects persist wholly through time, and perdurantism, the view that objects are extended in time and have temporal parts.

The methodological toolkit of persistenslogik includes temporal logic, such as linear temporal logic and branching temporal logic, as well as first-order logic augmented with time. Mereology, identity conditions, and potentially modal notions are integrated to capture persistence relations, continuity, and change. Researchers develop time-indexed predicates and operators to express that a property or relation remains true over an interval, or that an object endures from one time moment to another. Semantics may be model-theoretic, using time-parameterized interpretations, or employ possible-world frameworks extended with temporal structure.

Key issues addressed include the criteria for object identity over time, the problem of change, and how to represent persistence without collapsing distinctions between multiple temporal stages. Classic thought experiments, such as the Ship of Theseus, illustrate challenges in defining when a thing remains the same despite undergoing substantial alterations.

Applications of persistenslogik appear in philosophy, computer science, and information systems. In computer science, ideas about persistence relate to state continuity, object identity in databases and programming languages, and knowledge representation. The term persistenslogik is more common in Scandinavian contexts, while English-language discussions often frame the topic under persistence logic, temporal logic, or logic of persistence.