Inferring

It has been a commonplace from the beginnings of philosophical thought that what distinguishes humans from other species is the ability to reason; reason- ing is held to be an essential characteristic of the species and one that is unique to it. The essence condition requires that all humans possess at least the capacity for reasoning and that it be exercised in many of the ordinary cases of acquiring beliefs. And uniqueness entails that non-humans cannot reason, no matter how much their behavior resembles that of humans. I think that a certain specific model of reasoning has been presupposed by proponents of these claims. And there are grounds to believe that this model is inaccurate in essential respects: if reasoning does correspond to it, then few human beliefs are acquired through reason. However, given a more accurate description of what goes on in normal human reasoning, it is no longer plausible to think that only humans reason. So either the essence or the uniqueness claim must be given up. In this paper I argue for the second option.