Summary

Some philosophers argue that reflection, the ability to assess one’s reasons for beliefs, is the defining feature of rational thinking. Yet, by tying reflective thinking to language, they struggle to account for apparently rational behaviour in minimally verbal human infants and altogether exclude non-human animals. To assess capacities for a basic form of reflective thinking that does not require language, we investigated whether 2-year-old children, dogs, or pigs could acquire and respond to undermining defeaters. In an object-search task, subjects observed different informants act on one of two screens: one informant’s actions reliably indicated the reward location, while the other’s actions were independent of the reward location. The informants switched to using new actions twice during a sequence of repeated trials, which put subjects in the position to make an inference about the reliability of the informants based on the informativeness of their actions. Neither 2-year-olds nor animals responded differently to the Reliable and Unreliable informants. There was a reduction in subjects’ willingness to follow the indications of the informants in later trials, which was stronger in 2-year-olds than animals. While these results provide no evidence that 2-year-olds, dogs, or pigs made an inference about the reliability of each informant across the actions, reduced willingness to follow the informants’ indication suggests that they may be responding to either uncertainty or an undermining defeater like <the informants are unreliable>.

Summary

I challenge the view that reflection and language are essential to responsiveness to reasons from the standpoint of current analytic epistemology. After an introduction, in sections 2-4, I illustrate how the study of the cognitive abilities of very young children suggests that language and reflection are not necessary for responsiveness to reasons. In sections 5-6, I sketch a proposal in which both linguistic and non-linguistic subjects have access to the same broad rational abilities, if not to the same extent.

Summary

While growing empirical evidence suggests a continuity between human and non-human psychology, many philosophers still think that only humans can act and form beliefs rationally. In this paper, we challenge this claim. We first clarify the notion of rationality. We then focus on the rationality of beliefs and argue that, in the relevant sense, humans are not the only rational animals. We do so by first distinguishing between unreflective and reflective responsiveness to epistemic reasons in belief formation and revision. We argue that unreflective responsiveness is clearly within the reach of many animals. We then defend that a key demonstration of reflective responsiveness would be the ability to respond to undermining defeaters. We end by presenting some empirical evidence that suggests that some animal species are capable of processing these defeaters, which would entail that even by the strictest standards, humans are not the only rational animals.