ABSTRACT
Because it is more difficult for animals to correct a mistaken inference, any errors of inference can have graver consequences for the characteriza tion of animals. Therefore, it has been common practice in the study of animal behavior to avoid attributing human mental abilities to animals. During the last 2 decades, this practice has begun to be systematically challenged by those wishing to describe the evolution of human mental abilities and the cognitive abilities of animals (e.g., Griffin, 1978).
