Dialogic argumentation is a crucial component in many computational domains, and forms a core component of argumentation theory. This paper compares two approaches to dialogue that have grown from two different disciplines; the descriptive-normative approach of applied philosophy, and the formal, implemented approach of computer science. The commonalities between the approaches are explored in developing a means for representing dialogic argumentation in a common format. This common format uses an XML-based language that views locutions as state-changing operations, drawing on an analogy with classical artificial intelligence planning. This representation is then shown to hold a number of important advantages in areas of artificial intelligence and philosophy.