 The formulations of Schelling and Per Molander and the public goods game have the advantage of focusing attention on the PD quality of the game. Defection dominates cooperation, while universal cooperation is unanimously preferred to universal defection. Michael Taylor goes even further in this direction. His version of the many-person PD requires only the two PD-conditions just mentioned and the one additional condition that defectors are always better off when some cooperate than when none do. (Taylor's main concern is with the iterated version of this game, a topic that will not be addressed here.)