AFTD Auto-Formalizing Theoretical Domains

cnf_empty_satisfiable

theoremverified

The empty CNF formula has no clauses to satisfy, hence is satisfiable under any truth assignment.

Statement

theorem cnf_empty_satisfiable (V : Type*) : CnfSatisfiable (V := V) []
Verified
06 Sep 2026
Axioms
none — Lean reports it depends on no axioms
Built on 1
  • CnfSatisfiableA CNF formula (a list of clauses, each a list of literals) is satisfiable if there is a truth assignment such that every clause contains…

Lean source view module on GitHub

/-- The empty CNF formula is vacuously satisfiable. -/
theorem cnf_empty_satisfiable (V : Type*) : CnfSatisfiable (V := V) [] := ⟨fun _ => true, fun _ h => nomatch h⟩
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