= Kuhn's theorem
{c}
In a finite <extensive-form game> with <perfect recall>, each <mixed strategy> has a <realization-equivalent> <behavioural strategy>, and every <behavioural strategy> has a <realization-equivalent> <mixed strategy>. The latter direction samples all contingent actions independently in advance. For the former, condition the random complete plan on the player's own action and information history leading to an <information set>; <perfect recall> makes that own history common to its nodes. Conditional action <probabilities> then reproduce the terminal path factors. At an <information set> reached with zero probability under that player's own plan distribution, choose any action distribution. The result does not assert equivalence without <perfect recall>.<Extensive games and the problem of information by Harold W. Kuhn>[original article, pp. 193–216, perfect-recall equivalence]{ref}
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