 The field of informal logic is a recent invention, but one that continues historical attempts to understand and teach others how to argue. In the Western philosophical tradition, it begins with the sophists’ fifth century boast that they could teach others how to be successful arguers. In Aristotle it is manifest in his systematic account of reasoning, which is expressly designed to teach others how to argue well. Within the history of philosophy, one finds numerous other attempts to formulate accounts of argument that can be used to explain, evaluate, and teach real life reasoning. 