This book explains how burden of proof and presumption work as powerful devices in argumentation, based on studying many clearly explained legal and non-legal examples. It shows how the latest argumentation-based methods of artificial intelligence can be applied to these examples to help us understand how burdens of proof and presumptions work as devices of legal reasoning. It also shows the reader how to deal with presumptions and burdens of proof in everyday life, as they shift from one side to the other, sometimes confusingly, during a sequence of argumentation.