This essay reports on the evolution of our computer-supported argument diagramming and argument visualisation practices, as scholars of argument, and also as computer scientists interested in supporting the diagramming of argument. We begin with the Toulmin diagram, describe efforts to avoid boxes and arrows by using encapsulation, and efforts to depict the logic of legal argument from precedent. Our aim is to provide a theory of argumentation and a theory of legal precedent, and to provide visual correspondences for the logical rules. It is not our principal aim to provide tools for persuasive use, e.g., in a court of law. In the end, new possibilities for using text decoration and markup, dynamic text animation and interaction, and visual metaphor are envisioned. The possibilities are so rich that the final examples border on satire.
