Bipolar argument graphs represent the structure of complex pro and contra arguments for one or more standpoints. In this article, ampliative and exclusionary principles of evaluating argument strength in bipolar acyclic argumentation graphs are laid out and compared to each other. Argument chains, linked arguments, link attackers and supporters, and convergent arguments are discussed. The strength of conductive arguments is also addressed but it is argued that more work on this type of argument is needed to properly distinguish argument strength (...) from more general value-based components of such arguments. The overall conclusion of the article is that there is no justifiably unique solution to the problem of argument strength outside of a particular epistemological framework. (shrink)

This paper makes use of the concepts and theoretical framework developed within the field of Argumentation Theory to account for the structure and characteristics of abduction and of the comparative processes of weighing explanatory hypothesis. It elaborates an analysis of abduction based on its consideration as a meta-explanatory argumentation scheme while elucidating its relations with abductive reasoning and inference. The conceptualization of comparative processes of weighing explanatory hypothesis as complex and varied argumentative structures is presented as an alternative to the (...) idea of providing a formally rigid and supposedly universal account of ‘inference to the best explanation’. (shrink)

This paper makes use of the concepts and theoretical framework developed within the field of Argumentation Theory to account for the structure and characteristics of abduction and of the comparative processes of weighing explanatory hypothesis. It elaborates an analysis of abduction based on its consideration as a meta-explanatory argumentation scheme while elucidating its relations with abductive reasoning and inference. The conceptualization of comparative processes of weighing explanatory hypothesis as complex and varied argumentative structures is presented as an alternative to the (...) idea of providing a formally rigid and supposedly universal account of ‘inference to the best explanation’. (shrink)

Wellman identified three types of conductive arguments, the third of which contains both pro and counter-considerations in the same piece of reasoning. This paper provides a pragma-dialectical analysis of this type of argumentation, with special focus on argumentation reconstruction. It argues that the account of pro/con argumentation in the framework of argument-as-product has problems solvable by a pragma-dialectical approach. The paper asserts that pro/con argumentation should be analyzed as a dialectical strategy of a protagonist, where acknowledgement of counter-considerations shows that (...) the antagonist’s reasons have been taken into consideration, although the pro-considerations override them. Thus, the pro-considerations of pro/con argumentation should be interpreted as the protagonist’s overriding defeaters of the antagonist’s counter-arguments, the protagonist incorporating the latter as counter-considerations. The paper further argues that the pragma-dialectical framework needs an additional conceptual tool to properly reconstruct complex forms of pro/con argumentation. Finally, the pragma-dialectical approach to reconstruct pro/con argumentation has several advantages, especially to a more logical-structural approach to complex pro/con argumentation. (shrink)

This paper attempts to define the concept of critique, explain its function␣and properties and distinguish it from the close concept of evaluation. It is argued that, beyond the argument, a critique is concerned with the position of the proponent relatively to the reality the argument is about. Moreover, a critique is itself an argument in which assumptions regarding the position of the proponent are justified for a given audience on the basis of the proponent’s argumentative background within a specific domain.

Although argumentation plays an essential role in our lives, there is no integrated area of research on the psychology of argumentation. Instead research on argumentation is conducted in a number of separate research communities that are spread across disciplines and have only limited interaction. With a view to bridging these different strands, we first distinguish between three meanings of the word ?argument?: argument as a reason, argument as a structured sequence of reasons and claims, and argument as a social exchange. (...) All three meanings are integral to a complete understanding of human reasoning and cognition. Cognitive psychological research on argumentation has focused mostly on the first and second of these meanings, so we present perspectives on argumentation from outside of cognitive psychology, which focus on the second and third. Specifically, we give anoverview of the methods, goals, and disciplinary backgrounds of research on the production, the analysis, and the evaluation of arguments. Finally, inintroducing the experimental studies included in this special issue, which were conducted by researchers from a range of theoretical backgrounds, weunderline the breadth of argumentation research as well as stress opportunities for mutual awareness and integration. (shrink)

In this paper, it is argued that the most fruitful approach to developing normative models of argument quality is one that combines the argumentation scheme approach with Bayesian argumentation. Three sample argumentation schemes from the literature are discussed: the argument from sign, the argument from expert opinion, and the appeal to popular opinion. Limitations of the scheme-based treatment of these argument forms are identified and it is shown how a Bayesian perspective may help to overcome these. At the same time, (...) the contributions of the standard scheme-based approach are highlighted, and it is argued that only a combination of the insights of different traditions will yield a complete normative theory of argument quality. (shrink)

This article sets up a graph-theoretical framework for argumentation-analysis (dialectical analysis) which expands classical argument-analysis. Within this framework, a main theorem on the existence of inconsistencies in debates is stated and proved: the vicious circle theorem. Subsequently, two corollaries which generalize the main theorem are derived. Finally, a brief outlook is given on further expansions and possible applications of the developed framework.

This paper develops concepts and procedures for the evaluation of complex debates. They provide means for answering such questions as whether a thesis has to be considered as proven or disproven in a debate or who carries a burden of proof. While being based on classical logic, this framework represents an (argument-based) approach to non-monotonic, or defeasible reasoning. Debates are analysed as dialectical structures, i.e. argumentation systems with an attack- as well as a support-relationship. The recursive status assignment over the (...) arguments is conditionalised on proponents in a debate. The problem of multiple status assignments arising on circular structures is solved by showing that uniqueness can be guaranteed qua reconstruction of a debate. The notion of burden of proof as well as other discursive aims rational proponents pursue in a debate is defined within the framework. (shrink)

In theory, flawed arguments are not individually sufficient to justify a conclusion, but several may converge to do so. This is an empirical study of how arguers respond to a series of imperfect causal arguments during a serious conversation. People became less critical of the flawed arguments as more of the arguments appeared. The study gives empirical evidence that ordinary arguers permit sufficiency to accumulate during an extended discussion.