Abstract
Since at least the mid-1980s claims have been made for rationality in rats. For example,
that rats are capable of inferential reasoning (Blaisdell, Sawa, Leising, & Waldmann,
2006; Bunsey & Eichenbaum, 1996), or that they can make adaptive decisions about
future behavior (Foote & Crystal, 2007), or that they are capable of knowledge in
propositional-like form (Dickinson, 1985). The stakes are rather high, because these
capacities imply concept possession and on some views (e.g., Rödl, 2007; Savanah,
2012) rationality indicates self-consciousness. I evaluate the case for rat rationality by
analyzing 5 key research paradigms: spatial navigation, metacognition, transitive
inference, causal reasoning, and goal orientation. I conclude that the observed behaviors
need not imply rationality by the subjects. Rather, the behavior can be accounted
for by noncognitive processes such as hard-wired species typical predispositions or
associative learning or (nonconceptual) affordance detection. These mechanisms do not
necessarily require or implicate the capacity for rationality. As such there is as yet
insufficient evidence that rats can reason. I end by proposing the ‘Staircase Test,’ an
experiment designed to provide convincing evidence of rationality in rats.