Against the traditional view, Alvin Goldman argues that logic, probability theory, and linguistic analysis cannot by themselves delineate principles of rationality or justified belief. The mind's operations must be taken into account.

When is a testimony-based belief justified? According to so-called "Anti-Reductionism," the principle that a hearer is prima facie justified to take what another tells them at face value is true. I call this position "Liberal Foundationalism." I call it "liberal" for it is more liberal than "Moderate Foundationalism" that holds that perception-based beliefs are prima facie justified but testimony-based beliefs are not. Liberal Foundationalism has two interpretations: the principle is a contingent empirical truth, or an a priori necessary truth. I (...) call the view that the principle is a priori necessary "Liberal Fundamentalism." This chapter defends Liberal Fundamentalism against objections in the first half, and then in the second half it introduces "Weak Liberal Fundamentalism," the view that it is a priori necessary that testimony provides some epistemic support, but perhaps not enough, absent defeat, for knowledge. In later work I abandon the view that the principle is a priori necessary, but I still maintain the distinction between Strong and Weak variants of the principle, and the replies to many of the objections to the principle. (shrink)

Our folk epistemology says that if someone knows that P and tells you that P, then, given the absence of defeaters, if you believe what they tell you, you will come to know that P as well. A speaker's knowledge that P is then, for the most part, enough for a hearer to come to know that P. But there are counterexamples to this principle: testimonial knowledge does not always transfer from the speaker to the hearer. Why should that be (...) so? Because testimonial knowledge arises through the flow of information--from conclusive grounds--from the speaker through the speaker's assertion to the hearer's state of comprehension as of the speaker's assertion. A speaker's belief can be based on conclusive grounds, but the speaker's assertion may fail to provide conclusive grounds to the hearer. Then the hearer won't acquire knowledge, even from a knowledgeable speaker. Knowledge from testimony then works more like knowledge through perception. But wait, you say, that can't be so because testimony involves free will but perception does not. The essay ends with a broadly Hume inspired reply to this objection. (shrink)

We often talk about knowledge being transmitted via testimony. This suggests a picture of testimony with striking similarities to memory. For instance, it is often assumed that neither is a generative source of knowledge: while the former transmits knowledge from one speaker to another, the latter preserves beliefs from one time to another. These considerations give rise to a stronger and a weaker thesis regarding the transmission of testimonial knowledge. The stronger thesis is that each speaker in a chain of (...) testimonial transmission must know that p in order to pass this knowledge to a hearer. The weaker thesis is that at least the first speaker must know that p in order for any hearer in the chain to come to know that p via testimony. I argue that both theses are false, and hence testimony, unlike memory, can be a generative source of knowledge. (shrink)

Written by one of today's most creative and innovative philosophers, Ruth Garrett Millikan, this book examines basic empirical concepts; how they are acquired, how they function, and how they have been misrepresented in the traditional philosophical literature. Millikan places cognitive psychology in an evolutionary context where human cognition is assumed to be an outgrowth of primitive forms of mentality, and assumed to have 'functions' in the biological sense. Of particular interest are her discussions of the nature of abilities as different (...) from dispositions, her detailed analysis of the psychological act of reidentifying substances, and her critique of the language of thought for mental representation. In a radical departure from current philosophical and psychological theories of concepts, this book provides the first in-depth discussion on the psychological act of reidentification. (shrink)

Sanford Goldberg investigates the role that others play in our attempts to acquire knowledge of the world.

This paper states three counterexamples to the claim that testimony cannot generate knowledge, that a hearer can only acquire testimonial knowledge from a speaker who knows: a twins case, the fossil case, and an inversion case. The paper provides an explanation for why testimony can generate knowledge. Testimonial knowledge involves the flow of information from a speaker to a hearer through the linguistic channel.