Abstract

A theory of nonlinguistic thought is incomplete without an account of nonlinguistic reasoning and the norms of rationality by which such reasoning is governed. This chapter tries to show how an account of nonlinguistic rationality emerges when we pose the question: What could count as evidence that a nonlinguistic creature is behaving rationally? There are several different forms of evidence that can come into play here. At the most sophisticated level, a creature is behaving rationally when it is sensitive to the consequences of different courses of action, but there are types of rationality that do not involve such consequence-sensitivity. Different forms of rationality are appropriate to different types of explanation, and this chapter draws a distinction between level 1 rationality and level 2 rationality that maps onto the distinction between explanations of the type proposed by the minimalist and explanations that make use of belief-desire psychology.