Published online by Cambridge University Press: 14 May 2008
We address the claim that nonhuman animals do not represent unobservable states, based on studies of physical cognition by rooks and social cognition by scrub-jays. In both cases, the most parsimonious explanation for the results is counter to the reinterpretation hypothesis. We suggest that imagination and prospection can be investigated in animals and included in models of cognitive architecture.