This work arises from a series of lectures on paraconsistent logic delivered at the University of Groningen in the spring term of 1988. There followed a year later a schedule of lectures on Quine's philosophy of logic. The fruits of these endeavors circulated for awhile as The Groningen Lectures on Paraconsistent Logic. My efforts were graced by excellent students and generous colleagues. I am especially grateful to E. M. Barth, Jeanne Peijnenberg, Erik C. W. Krabbe, and David Atkinson for sharp criticism and helpful support. In 1990, a Fellowship at the Netherlands Institute for Advanced Study made it possible for me to join the research group on Fallacies as Violations of Rules for Argumentative Discourse. I worked there on conflict resolution strategies for intractable disagreements in questions of public policy. Only toward the end of my stay in Wassenaar did it occur to me that such strategies might be extended to contentious issues in the philosophy of logic and related fields. I owe much to the stimulation and encouragement of my NIAS colleagues: project leader Frans H. van Eemeren, the late Rob Grootendorst, Sally Jackson, Scott Jacobs, Agnès van Rees, Agnes Verbeist, Douglas Walton, and Charles Willard.

Thus was born a preoccupation with conflict resolution in the abstract sciences, which became the main business of my University of Lethbridge course on Deviant Logic in 1991 and 1992.