Morality Games 293 Fig. 2: The Hawk—Dove A D game. The Nash equilibria of the game are circled He |@ D@,) : 2 does not necessarily affect the payoffs, but does distinguish between the players, such as who arrived at the territory first or who built the object. If one conditions on the event (say, plays Hawk when she arrives first), then it is optimal for the other to condition on the event (to play Dove when the other arrives first). As our reader is likely aware, this was the logic provided by Maynard Smith to explain animal territoriality—why animals behave aggressively to defend territory that they have arrived at first, even if incumbency does not provide a defensive advantage and even when facing a more formidable intruder. Over the years, evi- dence has amassed to support Maynard Smith’s explanation, such as experimental manipulation of which animal arrives first (Davies, 1978; Sigg & Falett, 1985). Like other animals, we condition how aggressively we defend a resource on whether we arrive first. Because our behaviors are motivated by beliefs, we are also more likely to believe that the resource is “ours” when we arrive first. Studies have shown these effects with children’s judgments of ownership, in ethnographies of prelegal societies, and in computer games. In one such illustration, DeScioli and Wilson (2011) had research subjects play a computer game in which they contested a berry patch. Subjects who ended up keeping control of the patch usually arrived first, and this determined the outcome more often than differences in fighting ability in the game. This sense of ownership is codified in our legal systems, as illustrated by the quip “possession is 9/10ths of the law,’ and in a study involving famous legal property cases conducted by Descioli and Karpoff (2014). In a survey, these researchers asked participants to identify the rightful owner of a lost item, after reading vignettes based on famous property rights legal cases. Participants consisten