We outline a pragmatic-normative understanding of logic as a discipline that is completely anchored in the sphere of action, rules, means and ends: We characterize inferring as a speech act which is in need of regulation and we connect inferential rules with consequence relations. Furthermore, we present a scenario which illustrates how one actually assesses or can in principle assess the quality of logical rules with respect to justificatory questions. Finally, we speculate on the origin of logical rules as a means of supporting our practice of inferring.

Abstract. We argue that the need for commentary in commonly used linear calculi of natural deduction is connected to the "deletion" of illocutionary expressions that express the role of propositions as reasons, assumptions, or inferred propositions. We first analyze the formalization of an informal proof in some common calculi which do not formalize natural language illocutionary expressions, and show that in these calculi the formalizations of the example proof rely on commentary devices that have no counterpart in the original proof. We then present a linear natural deduction calculus that makes use of formal illocutionary expressions in such a way that unique readability for derivations is guaranteed  thus showing that formalizing illocutionary expressions can eliminate the need for commentary.

Peregrin and Svoboda propose an inferential and holistic approach to formalization, and a similar approach (to correctness) is considered by Brun. However, while the inferential criteria of adequacy explicitly endorsed by these authors may be holistic "in spirit," they are formulated for single formulas. More importantly, they allow the trivialization of equivalence and face problems when materially correct arguments come into play. Against this background, this paper tries to motivate holistic inferential criteria that compel us to distinguish carefully between non-trivially equivalent formalizations as well as between materially and logically correct arguments on an inferential basis.

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Using a short excerpt from Anselm’s Responsio as an example, this paper tries to present logical reconstruction as a special type of exegetical interpretation by paraphrase that is subject to (adapted) hermeneutic maxims and presumption rules that govern exegetical interpretation in general. As such, logical reconstruction will be distinguished from the non-interpretative enterprise of formalization and from the development of theories of logical form, which provide a framework in which formalization and reconstruction take place. Yet, even though logical reconstruction is dependent on methods of formalization, it allows us to use formal methods for the analysis and assessment of natural language texts that are not readily formalizable and is thus an important tool when it comes to applying the concepts and methods of formal logic to such texts.