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Added by: Berta Grimau, Contributed by: Patricia BlanchetteAbstract: Description: This article is a short overview of philosophical and formal issues in the treatment and analysis of logical consequence. The purpose of the paper is to provide a brief introduction to the central issues surrounding two questions: (1) that of the nature of logical consequence and (2) that of the extension of logical consequence. It puts special emphasis in the role played by formal systems in the investigation of logical consequence.
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Added by: Franci MangravitiAbstract:
Logical Pluralists maintain that there is more than one genuine/true logical consequence relation. This paper seeks to understand what the position could amount to and some of the challenges faced by its formulation and defence. I consider in detail Beall and Restall’s Logical Pluralism—which seeks to accommodate radically different logics by stressing the way that they each fit a general form, the Generalised Tarski Thesis (GTT)—arguing against the claim that different instances of GTT are admissible precisifications of logical consequence. I then consider what it is to endorse a logic within a pluralist framework and criticise the options Beall and Restall entertain. A case study involving many-valued logics is examined. I next turn to issues of the applications of different logics and questions of which logic a pluralist should use in particular contexts. A dilemma regarding the applicability of admissible logics is tackled and it is argued that application is a red herring in relation to both understanding and defending a plausible form of logical pluralism. In the final section, I consider other ways to be and not to be a logical pluralist by examining analogous positions in debates over religious pluralism: this, I maintain, illustrates further limitations and challenges for a very general logical pluralism. Certain less wide-ranging pluralist positions are more plausible in both cases, I suggest, but assessment of those positions needs to be undertaken on a case-by-case basis.
Comment: Makes for a nice counter in any course discussing Beall and Restall's pluralism. Given that the paper is a direct response, some previous familiarity with the topic is advised.
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Added by: Franci MangravitiAbstract:
Some writers object to logical pluralism on the grounds that logic is normative. The rough idea is that the relation of logical consequence has consequences for what we ought to think and how we ought to reason, so that pluralism about the consequence relation would result in an incoherent or unattractive pluralism about those things. In this paper I argue that logic isn’t normative. I distinguish three different ways in which a theory – such as a logical theory – can be entangled with the normative and argue that logic is only entangled in the weakest of these ways, one which requires it to have no normativity of its own. I use this view to show what is wrong with three different arguments for the conclusion that logic is normative.
Comment: Appropriate for any course touching on the normativity of logic question. Familiarity with the question and with logical pluralism is helpful, but not required. Could be paired with a defense of normativity for discussion.
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Added by: Giada Fratantonio and Berta GrimauAbstract: Description: Survey article on logical pluralism. The article is divided into three main parts: i) in the first one the author presents the main arguments for logical pluralism with respect to logical consequence; ii) in the second part, the author considers the relation between logical pluralism and Carnap's linguistic pluralism; iii) in the last section, the author considers further kinds of logical pluralism.
Comment: This article could be used as background or overview reading on logical pluralism. Suitable for a specialised, perhaps master's level course on logical pluralism or for a more general course on philosophy of logic touching on the topic.
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Added by: Berta GrimauAbstract: This paper deals with the adequacy of the model-theoretic definition of logical consequence. Logical consequence is commonly described as a necessary relation that can be determined by the form of the sentences involved. In this paper, necessity is assumed to be a metaphysical notion, and formality is viewed as a means to avoid dealing with complex metaphysical questions in logical investigations. Logical terms are an essential part of the form of sentences and thus have a crucial role in determining logical consequence. Gila Sher and Stewart Shapiro each propose a formal criterion for logical terms within a model-theoretic framework, based on the idea of invariance under isomorphism. The two criteria are formally equivalent, and thus we have a common ground for evaluating and comparing Sher and Shapiro philosophical justification of their criteria. It is argued that Shapiro's blended approach, by which models represent possible worlds under interpretations of the language, is preferable to Sher’s formal-structural view, according to which models represent formal structures. The advantages and disadvantages of both views’ reliance on isomorphism are discussed.
Comment: This paper provides an original view on the debate on the adequacy of the model-theoretic notion of logical consequence as well as a good overview of the relevant part of the debate. It can be used as standing on its own, but it can also serve as a complement to Sher (1996), also written by a female logician, and Shapiro (1998). Adequate for a general course on philosophy of logic or in a more specialized course on logical consequence. The paper is not technical, although students should've have taken at least an introductory logic course.
Comment: This article can be used as background or overview reading in a course on the notion of logical consequence. It could also be used in a general course on philosophy of logic having a section on this topic. It makes very little use of technical notation, even though familiarity with first-order logic is required. It closes with a useful list of suggested further readings.