Discussions about multimodal argumentation have long been hindered by doubts about whether non-verbal artifacts can express propositions. The opponents of multimodal argumentation have stated that semiotic modes other than language lack the precision required to express verifiable statements about the world. The aim of this article is to demonstrate that the account of propositions presented in speech act theory is suitable for analyzing multimodal communication, which is why multimodal argumentation can be studied in the pragma-dialectical tradition. By connecting Searle’s approach with the pragma-dialectic argumentation schemes, I suggest that the propositional act is constructed of three, and not two, elements: referring expression, predicating quality, and proposition scheme, the latter being a characterization of the relationship between the first two. I derive proposition schemes directly from argumentation schemes, noticing that the pragma-dialectical argumentation schemes actually characterize the relationship within propositions, and not between them. Based on that notion, I argue that when interacting with seemingly ambiguous multimodal artifacts, the receiver automatically chooses the most probable connection between the referring expression and the predicating quality from the list of proposition schemes, explaining why multimodal communication can be easily interpreted intuitively. Finally, I analyze several argumentative examples to illustrate how the proposition schemes can be used in reconstructing the reasoning expressed multimodally.

AbstractAccording to a dialectical approach to argumentation, a single argument can be seen as a dialogical "Why? Because!" sequence. Does this also apply to multimodal arguments? This paper focuses on multimodal arguments with a predominantly visual character and shows that dialogues are helpful for identifying and reconstructing arguments in multimodal communication. To include nonverbal arguments in dialectical argumentation theory, it is proposed to regard dialogue as mode-fluid. The account of multimodal argument as dialogue will be compared with Champagne and Pietarinen’s account of visual argument as movement.

During the last decade, one source of debate in argumentation theory has been the notion that there are different modes of arguing that need to be distinguished when analyzing and evaluating arguments. Visual argument is often cited as a paradigm example. This paper discusses the ways in which it and modes of arguing that invoke non-verbal sounds, smells, tactile sensations, music and other non-verbal entities may be defined and conceptualized. Though some attempts to construct a ‘multimodal’ theory of argument are criticized, it advocates for an argumentation theory that makes room for visual arguing and for other non-verbal modes that have not been explored in depth. In the process, the paper provides a method for identifying the structure of multimodal arguments and argues that adding modes to our theoretical tool box is an important step toward a comprehensive account of argument.