Social Choice.Voting.Arrow

Theorem Arrow's Impossibility Theorem staged

Theorem Arrow's Theorem via Decisive Coalitions staged

Theorem Coalition Contraction — Splitting a Decisive Coalition staged

Definition Decisive Coalition and Dictator formalized

Definition Decisive Coalition for an Ordered Pair formalized

Theorem Field Expansion — Decisive on One Pair Implies Decisive Everywhere staged

Theorem Grand Coalition Is Decisive under Unanimity staged

Lemma IIA on Strict Preference staged

Theorem Minimal Decisive Coalition Has Size One staged

Definition Weakly Decisive Coalition formalized