Abstract

I argue that the evolutionary history of anger has substantive implications for normative ethics. In the process, I develop an evolutionary account of anger and its influence on action. First, I consider a prominent argument by Peter Singer and Joshua Greene. They conclude that evolutionary explanations of human cooperation debunk – or undercut the evidential value of – the moral intuitions supporting duty ethics (as opposed to utilitarian or consequentialist ethics). With this argument they aim to defend consequentialist theories. However, their argument also threatens to debunk intuitions that support consequentialist theories. I give a novel argument that overcomes this difficulty. Specifically, I offer an evolutionary story about anger that can explain retributive, duty-oriented intuitions concerning punishment. This explanation debunks these intuitions (and not others) by showing that they were selected for their biological consequences rather than their accuracy (concerning duties to punish). I develop this explanation by raising and resolving three additional problems. First, prominent evolutionary explanations of retributive motives fail because they appeal to models that apply only to organisms with strategic insight. To mitigate this problem, I explain the existence of a retributive-like motive in rodents by appealing to an economic model of resource competition, which applies to organisms without strategic insight. Second, I show that human anger was shaped by resource competition of this kind. To do so, I develop evidential criteria to determine when psychological systems in different species share common evolutionary origins. I deploy these criteria to argue that human anger and the retributive motive in rodents derive from the same ancestral trait. Finally, the continuity of anger across human and nonhuman animals stands in tension with the idea that anger causes purposive behavior like retribution or retaliation. I argue that differences between the angry behaviors of human and nonhuman animals are differences in degree and not in kind. In the end, this evolutionary story both explains and undermines retributive intuitions, but not in the straightforward way that Singer and Greene suppose.