Rigorous Reasoning

Concept · Foundations

Rigid Designator

A term that picks out the same object in every possible world in which that object exists, as opposed to terms whose reference can shift across worlds.

Why it matters

Rigidity is the key tool for analyzing necessary identity claims and essential properties in quantified modal logic.

Where this shows up

Units and lessons using this concept

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Related

Other concepts in Foundations

A, E, I, O PropositionsAccessibility RelationArgumentAtomic StatementAuthorial IntentBase RateBayes FactorBurden of Proof in InterpretationCalibrationCardinalityCartesian ProductCategorical Proposition