 One of the notions that Clavien and Chapuisat find playing a role in evolutionary anthropology, evolutionary game theory and experimental economics is what they call “preference altruism”. “An action is altruistic”, in this sense, “if it results from preferences for improving others’ interests and welfare at some cost to oneself” (2013: 131). Though the agent’s psychology is relevant, on this account of altruism, there is no mention of the agent’s ultimate desires. Thus an action can be preference altruistic even if the agent’s preference for improving someone else’s welfare is an instrumental preference engendered by the belief that improving the recipient’s welfare will contribute to the agent’s own pleasure or treasure. 