The Epistemology of Testimony-Based Knowledge and Justification

Abstract

Testimony is a special challenge in epistemology. Human life as we know it would be impossible without it; we commonly accept it without question; and only the highly skeptical doubt that from it we gain much knowledge about matters on which we lack independent evidence. In my theory of testimony, it figures as an essential source of knowledge in our lives, but not as a basic source of it; and the way in which testimony yields justification for believing its content is very different from the way in which it yields knowledge. Isabelle Keßels, David Lambert, and Christian Quast have produced a long and detailed study of my treatment of the topic, and here I can note only some important aspects of it and seek to discuss them in ways that may advance understanding of some major aspects of the topic.