Learning from Words * By JENNIFER LACKEY

Abstract

While much of our knowledge relies on testimony or the words of others, until recently few philosophers had much to say about the nature of testimony or how we learn from another's words, but testimony has now become a popular topic. Jennifer Lackey's Learning from Words: Testimony as a Source of Knowledge is a useful and intelligent guide, a well informed and appreciative but critical and provocative commentary on a large and growing body of literature. According to Lackey, most of the literature assumes that testimony can spread but not create knowledge, much as memory can be a reminder of old but not a source of new truth. Lackey maintains that the assumption is mistaken and offers an account of testimony, according to which, testimony can give rise to new knowledge as well as transmit old truths from one person to another. In her introduction, Lackey characterizes what she calls the belief view of testimony (BVT) and suggests that this view dominates today's literature. On the belief view, testimony is a vehicle for expressing belief, and when I tell you that p, I express my belief that p with the intention that you believe that p based on my saying so. On the belief view, my testimony gives you a reason to believe that p only if I believe and have good reason to believe that p. As a result, you cannot know that p based on my testimony unless I believe that p myself. Lackey calls this the transmission thesis (TT) (that knowledge is acquired through testimony when speakers transmit their beliefs to others). Lackey argues, however, that you can know that p based on my testimony whether I believe that p or not, for what matters is not what I believe but whether my statement is reliable. She calls this the statement view of testimony (SVT) and maintains that SVT best explains how we learn from the words of others.