ABSTRACT
A full consideration of the moral status of the other animals – the non-humans – is a life's project. Animals have goals and interests – what Bernard Rollin calls a telos – and the frustration of these is generally bad for the animal. Although a number of Jeff McMahan's claims about the psychological lives of animals are empirical, he offers no evidence in support of them. Some of them may be true, although the literatures on comparative cognition and animal cognitive ethology suggest that for a great number of species the situation is far more complicated than McMahan intimates. McMahan thinks persons are of incalculable worth in virtue of some set of psychological capacities, although he remains agnostic on the precise nature of the capacities in the set save that they should differentiate humans from other animals. The cost would be a radical reformation of moral judgments and practices regarding the other animals.
