Modal Logic and Belief
This quiz covers the basics of Modal Logic and Belief, including the concepts of possibility, necessity, and belief.
Questions
Which of the following is a modal operator?
- *
- +
- !
- ?
What is the dual of the possibility operator ?
- *
- +
- !
- ?
What is the formula for the law of necessitation?
- $ \vdash \phi \rightarrow \Box \phi $
- $ \vdash \Box \phi \rightarrow \phi $
- $ \vdash \phi \rightarrow \Diamond \phi $
- $ \vdash \Diamond \phi \rightarrow \phi $
What is the formula for the law of distribution of conjunction over possibility?
- $ \Diamond (\phi \wedge \psi) \leftrightarrow \Diamond \phi \wedge \Diamond \psi $
- $ \Diamond (\phi \vee \psi) \leftrightarrow \Diamond \phi \vee \Diamond \psi $
- $ \Box (\phi \wedge \psi) \leftrightarrow \Box \phi \wedge \Box \psi $
- $ \Box (\phi \vee \psi) \leftrightarrow \Box \phi \vee \Box \psi $
What is the formula for the law of distribution of disjunction over necessity?
- $ \Box (\phi \wedge \psi) \leftrightarrow \Box \phi \wedge \Box \psi $
- $ \Box (\phi \vee \psi) \leftrightarrow \Box \phi \vee \Box \psi $
- $ \Diamond (\phi \wedge \psi) \leftrightarrow \Diamond \phi \wedge \Diamond \psi $
- $ \Diamond (\phi \vee \psi) \leftrightarrow \Diamond \phi \vee \Diamond \psi $
What is the formula for the axiom of reflexivity for belief?
- $ \vdash B\phi \rightarrow \phi $
- $ \vdash \phi \rightarrow B\phi $
- $ \vdash \Diamond B\phi \rightarrow B\phi $
- $ \vdash B\phi \rightarrow \Diamond B\phi $
What is the formula for the axiom of positive introspection for belief?
- $ \vdash B\phi \rightarrow B B\phi $
- $ \vdash B B\phi \rightarrow B\phi $
- $ \vdash \Diamond B\phi \rightarrow B\phi $
- $ \vdash B\phi \rightarrow \Diamond B\phi $
What is the formula for the axiom of negative introspection for belief?
- $ \vdash B\phi \rightarrow B B\phi $
- $ \vdash B B\phi \rightarrow B\phi $
- $ \vdash \Diamond B\phi \rightarrow B\phi $
- $ \vdash B\phi \rightarrow \Diamond B\phi $
What is the formula for the rule of necessitation for belief?
- $ \vdash B\phi \rightarrow B \Box B\phi $
- $ \vdash B \Box B\phi \rightarrow B\phi $
- $ \vdash \Diamond B\phi \rightarrow B\phi $
- $ \vdash B\phi \rightarrow \Diamond B\phi $
What is the formula for the rule of distribution of belief over conjunction?
- $ \vdash B(\phi \wedge \psi) \leftrightarrow (B\phi \wedge B\psi) $
- $ \vdash B(\phi \vee \psi) \leftrightarrow (B\phi \vee B\psi) $
- $ \vdash \Diamond B\phi \rightarrow B\phi $
- $ \vdash B\phi \rightarrow \Diamond B\phi $
What is the formula for the rule of distribution of belief over disjunction?
- $ \vdash B(\phi \wedge \psi) \leftrightarrow (B\phi \wedge B\psi) $
- $ \vdash B(\phi \vee \psi) \leftrightarrow (B\phi \vee B\psi) $
- $ \vdash \Diamond B\phi \rightarrow B\phi $
- $ \vdash B\phi \rightarrow \Diamond B\phi $
What is the formula for the rule of generalization for belief?
- $ \vdash B\phi \rightarrow B \forall x \phi $
- $ \vdash B \forall x \phi \rightarrow B\phi $
- $ \vdash \Diamond B\phi \rightarrow B\phi $
- $ \vdash B\phi \rightarrow \Diamond B\phi $
What is the formula for the rule of instantiation for belief?
- $ \vdash B\forall x \phi \rightarrow B\phi [t/x] $
- $ \vdash B\phi [t/x] \rightarrow B\forall x \phi $
- $ \vdash \Diamond B\phi \rightarrow B\phi $
- $ \vdash B\phi \rightarrow \Diamond B\phi $
What is the formula for the rule of modus ponens for belief?
- $ \vdash B(\phi \rightarrow \psi) \wedge B\phi \rightarrow B\psi $
- $ \vdash B(\phi \rightarrow \psi) \wedge B\psi \rightarrow B\phi $
- $ \vdash \Diamond B\phi \rightarrow B\phi $
- $ \vdash B\phi \rightarrow \Diamond B\phi $