" Apes do evidently understand what others are doing, and they can prudently do the same, in which sense they "cooperate"—for their own reasons. But they lack the ability to symbolically par­ticipate in others' existence and thus communalize their own. [...]

"Traditional models of economic decision-making assume that peo­ple are self-interested rational maximizers. Empirical research has demonstrated, however, that people will take into account the inter­est of others and are sensitive to norms of cooperation and fairness. [...] Here we show that in an ultimatum game, humans' closest living relatives, chimpanzees (Pan troglodytes), are rational maximizers and are not sensitive to fairness. These results support the hypothesis that other-regarding preferences and aversion to inequitable outcomes, which play key roles in human social organization, distinguish us from our clos­est living relatives." {Jensen, Call, and To masello 2007, 107; see also Jensen et al. 2006)

So much, then, for the dismal economic science—whose future is not bright either, inasmuch as chimpanzees are disappearing. "

― Marshall Sahlins , What Kinship Is-And Is Not