Philosophy professor emeritus J. Anthony Blair, a senior research fellow with the Centre for Research in Reasoning, Argumentation and Rhetoric, will discuss the nature of his field Wednesday in his free public lecture, “What is informal logic, anyway?”

Informal logic’s critics focus on certain entries in textbooks for argument analysis courses, says Blair.

“I describe how various research themes emerged from a combination of a turn to public domain natural language arguments for the subject of application, and a rejection of deductive validity as the exclusive norm,” he says.

The lecture begins at 4 p.m. April 2 in room 209, Essex Hall.