 Revealed preference theory is nonredundantly relevant, Ross claims, because it makes sense of patterns like intentionality and agency that don’t reduce to physical patterns. To the extent that this is not merely a predictive but an explanatory task, one needs to admit the existence of these patterns, thus endorsing “intentional stance functionalism without sliding into instrumentalism” (Ross 2005, 143–4). According to such a view, preferences are identified by the causal roles they play in generating human, animal and machine behaviour; and they are real to the extent that the best theories of such behaviour require their attribution.