At the time G. Thomas Goodnight published his essay on spheres of argument, which he called "a speculative inquiry into the art of public deliberation," the "hot topic" within argumentation studies was argument fields ("Speculative" 214). Scholars had picked up on a term first used by Stephen Toulmin in The Uses of Argument. There Toulmin maintained that two arguments were in the same field if their data and conclusions were of the same "logical type" (Uses 14). (In this formulation, "logical type" was left undefined.) This was an effort to find a standard for evaluating arguments that recognized a middle ground between whimsy and caprice, on one hand, and formal deduction on the other. Toulmin was engaged in the same general project as Chaim Perelman and Lucie Olbrechts-Tyteca: revitalizing the concept of the reasonable. He was implying that arguments should not be evaluated purely on their effectiveness, nor should they be dependent on formal requirements. Instead, they should be judged in the context of other arguments with the same types of data and inference.
By the late 1960s, however, Toulmin had moved away from this notion of fields and had come to regard them as akin to academic disciplines. In Human Understanding, he distinguished among compact, diffuse, and would-be disciplines as well as the undisciplined and the undisciplinable. He implied that arguments within a given discipline could be assessed only by those who belonged to that discipline and who had the specific training and knowledge that it required and presumed. Now membership in an argument field was a characteristic not of arguments but of arguers; fields defined distinctive argument communities. This being so, the question of how to differentiate argument fields was a matter of great importance. If an argument could be understood, say, as falling either within the field of science or the field of religion, the choice of field might well be a decision about which side of the argument would prevail. There was extensive discussion on conference programs and in the pages of this journal about whether fields should be defined by academic disciplines, or by broad-based world-views (Marxism and behaviorism, for example), or by the purpose of the arguers, or in some other way. The central theoretical issue was what to do about arguments that could be situated in more than one field or that seemed to transcend field boundaries.
Fields were useful for matching arguments with the professional communities of those interested in them, but the concept left important unanswered questions: Was it better for an argument to reside in one field or another, if there is a choice? Were all fields, in principle, equal and on the same plane? Was public affairs itself an argument field, or did it somehow stand apart from all argument fields, belonging to an altogether different category of discourse? And if the latter, did public argument trump field-based argument, or vice versa? Intuitively, it seemed that the concept of argument fields was of great value, and yet the concept seemed to be almost inherently vague.
The combination of significance and ambiguity motivated scholarly attention. One track at the second biennial Alta conference, in 1981, was devoted to argument fields (Ziegelmueller and Rhodes). In part, it offered a theoretically broader perspective for long-standing interest in studying legal argumentation. Discourse conventions of lawyers, July deliberations, structures of reasoning in the judicial opinion, and similar topics now could be seen as valuable not only in their own right, esoteric as they might seem, but also as a powerful case study of an argument field. Similarly, the field concept helped to warrant emerging areas of study in scientific argumentation, political argumentation...