Add to ORKGThis paper introduces and argues for the hypothesis that judgments of testimonial worth are central to our practice of normatively appraising speech. It is argued that judgments of testimonial worth are central both to the judgement that an agent has lied, and to the acceptance of testimony. The hypothesis that, in lying, an agent necessarily displays poor testimonial worth, is shown to resolve a new puzzle about lying, and the recalcitrant problem raised by the existence of bald faced lies, and selfless assertions. It is then shown that the notion of testimonial worth allows us to capture the distinction between taking a speaker at their word, and treating them as a mere indicator of the truth in a way other theories fail to do