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Accessibility Relation · Rigorous Reasoning · Rigorous Reasoning

Concept · Foundations

Accessibility Relation

A relation between possible worlds that says which worlds count as 'available' from a given world when evaluating modal operators.

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Why it matters

Different accessibility relations yield different modal systems and determine which modal axioms are valid in a given setting.

Where this shows up

Units and lessons using this concept

Following the links will take you to the page where this term is introduced in context.

Units (1)

Modal Logic: Necessity, Possibility, and CounterfactualsStudents learn to reason about necessity, possibility, and counterfactual conditionals using the box and diamond operators, possible-worl…

Lessons (2)

Counterfactuals and Possible WorldsModal Logic: Necessity, Possibility, and Counterfactuals The Modal Operators and Their RulesModal Logic: Necessity, Possibility, and Counterfactuals

Related

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