On the utility of descriptive diagrams for the analysis and criticism of arguments

Argument diagrams, especially Stephen Toulmin's “layout,” have enjoyed wide popularity, but the theoretical assumptions behind the use of such diagrams are very suspect. Diagrams are linguistically biased; they abstract arguments out of social contexts; and it is impossible to clearly define and delimit the phenomena they represent. The disadvantages of their use outweigh any conceptual advantages they might provide, and the rhetorical critic and argumentation theorist are enjoined to eschew their use.