著者

渡部 洋一郎

出版者

日本読書学会

雑誌

読書科学 (ISSN:0387284X)

巻号頁・発行日

vol.58, no.1, pp.1-16, 2016-03-31 (Released:2017-01-12)

参考文献数

14

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The Toulmin Model has traditionally been used as a framework for discerning the structure of an argument and as a model for analyzing the relations among the elements in an argument. In recent years, many advocates have claimed that the model can serve as a foundation for cultivating argumentation abilities. Furthermore, some studies have mentioned benefits from using the Toulmin Model, such as allowing for due consideration of the uncertain elements in everyday logic and making easy-to-overlook problems more obvious by differentiating between the evidence and the reason within the argumentation process. However, despite these benefits, the following questions have also arisen:(1) Why is Backing (B) required for Warrants (W), but not for Datum (D)?(2) Should the attachment of Qualifiers (Q) and Rebuttal (R) to Datum (D) and Warrants (W) depend on the situation?(3) Can Backing (B) be regarded as corresponding to Datum (D) when considering Warrants (W) as one Claim (C)?These questions suggest that there is room for modification in the model's six-item layout.Aiming to answer these questions, this paper argues for the following four conclusions with respect to questions (1) and (2). First, as a consequence of Warrants (W) being hypothetical statements and implicitly demonstrated elements, Backing (B) elements are necessary to categorically prove that Warrants (W) are justifiable. Second, since Warrants (W) are broad facts that retain a degree of ambiguity inherent within conjectures and interpretations, Backing (B) can reduce the ambiguity of Warrants (W) themselves, and increase their certainty, whilst simultaneously providing Warrants (W) with logical grounds as a premise. Third, even if Datum (D) is a categorical statement of a fact, there is a broader assertion that cannot be qualified by this element alone. Fourth, as a consequence of ambiguities that cannot eliminate the latent uncertainties within Warrants (W), adverbial phrases such as “probably” and “perhaps” should be required as Qualifiers (Q).Based on these conclusions, this paper proposes a new layout of the Toulmin Model for the process of argumentation, by discussing, among other topics, whether it is possible to treat Datum (D) as a categorical statement of fact or Warrants (W) as universal propositions.