Inference to the Best Explanation and the Receipt of Testimony

The chapter develops a local reductionist account of what is required for testimonial beliefs to be justified, and argues that human recipients of testimony typically form their beliefs in accordance with these requirements. Recipients estimate the trustworthiness of a speaker’s assertion by constructing a mini-psychological theory of her, arriving at this by inference to the best explanation, and accept what they are told only if this theory has it that the speaker is expressing her knowledge. The existence of a social norm governing assertion, the knowledge norm, is a key factor making such an explanation accessible to recipients. This local reductionism supports explanationism as a general account of the justification of empirical beliefs.