Johnson, Fred (Frederick A.), authorSICSAT, publisher2007-01-032007-01-031991Johnson, Fred, Suppositional Reasoning. van Eemeren, Frans H., Rob Grootendorst, J. Anthony Blair, Charles A. Willard, eds., Proceedings of the Second International Conference on Argumentation, June 19-22, 1990, 281-287. Amsterdam: SICSAT, 1991.http://hdl.handle.net/10217/86331The purpose of this paper is to show how to structure some typical examples of suppositional reasoning. Such reasoning is common, but unfortunately it is typically neglected by writers of logic textbooks, as Fisher points out in [Fisher, p. viii]. Fisher gives a method of diagramming suppositional reasoning and gives credit to Thomas for similar work in [Thomas]. I shall begin by laying out their methods of structuring suppositional reasoning.born digitalpreliminarieseng©1991 SICSAT.Copyright and other restrictions may apply. User is responsible for compliance with all applicable laws. For information about copyright law, please see https://libguides.colostate.edu/copyright.reductiosconditionalizationText