To have an overview of research done in informal logic, it is necessary to have a way to classify the work, says philosophy professor Hans V. Hansen.

“An ideal set of categories would be complete, determinate, and useful,” he says.

• Complete: every item of research in the data base should fit into one or another of the categories.
• Determinate: every item in the data base should fit into only one of the categories.
• Useful: the purpose of the classification should be clear and guide the selection of categories.

Dr. Hansen, a fellow of the Centre for Research in Reasoning, Argumentation, and Rhetoric, will lead a discussion seminar on the topic, entitled “Classifying argumentation research,” Thursday, November 6, at 4 p.m. in room 209, Essex Hall.

He acknowledges his guidelines above require more thought and elaboration and invites participants to bring their own ideas to the discussion.