This paper uses argument diagrams, argumentation schemes, and some tools from formal argumentation systems developed in artificial intelligence to build a graph-theoretic model of relevance shown to be applicable as a practical method for helping a third party judge issues of relevance or irrelevance of an argument in real examples. Examples used to illustrate how the method works are drawn from disputes about relevance in natural language discourse, including a criminal trial and a parliamentary debate.

In this paper it is shown how plausible reasoning of the kind illustrated in the ancient Greek example of the weak and strong man can be analyzed and evaluated using a procedure in which the pro evidence is weighed against the con evidence using formal, computational argumentation tools. It is shown by means of this famous example how plausible reasoning is based on an audience’s recognition of situations of a type they are familiar with as normal and comprehensible in their (...) shared common knowledge. The paper extends previous work on this example by using three new multiagent argumentation schemes closely related to the scheme for argument from negative consequences. (shrink)

In the domain of medical science, factual evidence is usually considered as the criterion on which to base decisions and construct hypotheses. Evidence-based medicine is the translation of this approach into the field of patient care, and it means providing only the type of care that is based on evidence that proves its effectiveness and appropriateness. However, while the literature has focused on the types and force of evidence used to establish the recommendation and treatment guidelines, the problem of how (...) evidence is used in doctor–patient interactions to motivate, or refuse, treatment or habit change has been almost completely neglected. In this specific context, characterized by the epistemic unbalance between the interlocutors and a specific conversational goal, the scientific categories of evidence are often irrelevant. The goal of this paper is to address this challenge by analyzing the role evidence plays in doctor–patient interactions in diabetes care. After introducing an analytical distinction between the epistemic and the pragmatic aspect of evidence, we will propose a classification of the types and functions of evidence in chronic care communication, and illustrate its possible uses through its application to our corpus of diabetes-care consultations. From our qualitative analyses, it is possible to observe how in this communicative context a crucial role is played by the conflicts of evidence, in which providers correct patients’ uses of evidence leading them to using less defeasible levels of evidence. (shrink)

The detection and analysis of misunderstandings are crucial aspects of discourse analysis, and presuppose a twofold investigation of their structure. First, misunderstandings need to be identified and, more importantly, justified. For this reason, a classification of the types and force of evidence of a misunderstanding is needed. Second, misunderstandings reveal differences in the interlocutors’ interpretations of an utterance, which can be examined by considering the presumptions that they use in their interpretation. This paper proposes a functional approach to misunderstandings grounded (...) on presumptive reasoning and types of presumptions, in which incompatible interpretations or interpretative failures are examined as defaults of the underlying interpretative reasoning, caused by overlooked evidence or conflicting presumptions. Moreover, it advances a classification of the types and the probative weights of the evidence that can be used to detect misunderstandings. The proposed methodology and its implications are illustrated through the analysis of doctor–patient communication in diabetes care. (shrink)

The notions of inference and default are used in pragmatics with different meanings, resulting in theoretical disputes that emphasize the differences between the various pragmatic approaches. This paper is aimed at showing how the terminological and theoretical differences concerning the two aforementioned terms result from taking into account inference and default from different points of view and levels of analysis. Such differences risk making a dialogue between the theories extremely difficult. However, at a functional level of analysis the different theories, (...) definitions, and approaches to interpretation can be compared and integrated. At this level, the standardization of pragmatic inferences can be regarded as the development of a specific type of presumptions, used to draw prima-facie interpretations. (shrink)

This paper advances an approach to presupposition rooted in the concept of commitment, a dialectical notion weaker than truth and belief. It investigates ancient medieval dialectical theories and develops the insights thereof for analyzing how presuppositions are evaluated and why a proposition is presupposed. In particular, at a pragmatic level, presuppositions are reconstructed as the conclusions of implicit arguments from presumptive reasoning, grounded on presumptions of different type and nature. A false (or rather unaccepted) presupposition can be thus represented as (...) the outcome of a conflict of presumptions – the ones used by the Speaker and the ones commonly accepted or backed by evidence. From an interpretative perspective, this defaulted presumptive reasoning can be explained by comparing the available presumptions and repaired by replacing the weaker and unacceptable ones. (shrink)

Metaphors are considered as instruments crucial for persuasion. However, while their emotive, communicative and persuasive effects are the focus of different studies and discussions, the core of their persuasive function, namely their argumentative dimension, is almost neglected. This paper addresses the problem of explaining how metaphors can communicate arguments, and how it is possible to reconstruct and justify them. To this purpose, a distinction is drawn between the arguments that are communicated metaphorically and reconstructed “top down,” namely based on relevance (...) considerations, and the ones that are triggered implicitly by the use of a metaphorical expression. In both cases, metaphorical arguments are reconstructed through different patterns of argument, called argumentation schemes (Walton, Reed & Macagno 2008). However, while the purpose of a metaphorical sequence of discourse (called metaphorical move) can guide and justify the reconstruction of the argument that can sufficiently support the intended conclusion in a persuasive move, a more complex analysis is needed for analyzing the inferences that a metaphorical move can trigger. These inferences are claimed to represent part of the connotation of the metaphorical expression and can be captured through its most frequent collocations, determinable using some tools of the corpus linguistics. (shrink)