A Milgrom, North, & Weingast paper proposed an “adjusted” variant of this approach applied to the “Law Merchant” system. This approach is worse when subject to “echo effects,” which was proven against an algorithm developed by Johann Joss. One book articulates the effectiveness of this approach due to its properties of “clarity,” “niceness,” “retaliatory,” and “forgiving.” A version of this approach seeking to avoid a “death spiral” (15[1])inserts the number (*) “two” in its name. Robert Axelrod’s The (-5[1])Evolution of Cooperation primarily analyzes this “nice” strategy, which was determined to be the best solution in a tournament (10[1])using the iterated prisoner’s dilemma. This trigger strategy differs from the grim trigger by not enforcing maximal punishment for defection. For 10 points, name this game theory strategy in which a player cooperates and then copies their opponent’s previous action. ■END■ (10[1])