In one volume it covers: Unit 1. Credibility of evidence; how context can affect credibility; issues of perception, language, interpretation, and judgement; different types of evidence; results of bias; possible weaknesses and strengths; using a credibility calculus; judging a case. Unit 2. Assessing and developing argument; differences between arguments and other forms of persuasion; what forms arguments can take; the nature of conclusions; assumptions and evidence; evaluating arguments; special kinds of argument content; producing arguments.