On an Intuitionistic Logic for Pragmatics

We reconsider the pragmatic interpretation of intuitionistic logic [21] regarded as a logic of assertions and their justications and its relations with classical logic. We recall an extension of this approach to a logic dealing with assertions and obligations, related by a notion of causal implication [14, 45]. We focus on the extension to co-intuitionistic logic, seen as a logic of hypotheses [8, 9, 13] and on polarized bi-intuitionistic logic as a logic of assertions and conjectures: looking at the S4 modal translation, we give a denition of a system AHL of bi-intuitionistic logic that correctly represents the duality between intuitionistic and co-intuitionistic logic, correcting a mistake in previous work [7, 10]. A computational interpretation of cointuitionism as a distributed calculus of coroutines is then used to give an operational interpretation of subtraction.Work on linear co-intuitionism is then recalled, a linear calculus of co-intuitionistic coroutines is dened and a probabilistic interpretation of linear co-intuitionism is given as in [9]. Also we remark that by extending the language of intuitionistic logic we can express the notion of expectation, an assertion that in all situations the truth of p is possible and that in a logic of expectations the law of double negation holds. Similarly, extending co-intuitionistic logic, we can express the notion of conjecture that p, dened as a hypothesis that in some situation the truth of p is epistemically necessary

A Pragmatic Interpretation of Quantum Logic

Scholars have wondered for a long time whether the language of quantum mechanics introduces a quantum notion of truth which is formalized by quantum logic (QL) and is incompatible with the classical (Tarskian) notion. We show that QL can be interpreted as a pragmatic language of assertive formulas which formalize statements about physical systems that are empirically justified or unjustified in the framework of quantum mechanics. According to this interpretation, QL formalizes properties of the metalinguistic notion of empirical justification within quantum mechanics rather than properties of a quantum notion of truth. This conclusion agrees with a general integrationist perspective that interprets nonstandard logics as theories of metalinguistic notions different from truth, thus avoiding incompatibility with classical notions and preserving the globality of logic. By the way, some elucidations of the standard notion of quantum truth are also obtained. Key words: pragmatics, quantum logic, quantum mechanics, justifiability, global pluralism.Comment: Third version: 20 pages. Sects. 1, 2, and 4 rewritten and improved. Explanations adde

The Logical Burdens of Proof. Assertion and Hypothesis

The paper proposes two logical analyses of (the norms of) justification. In a first, realist-minded case, truth is logically independent from justification and leads to a pragmatic logic LP including two epistemic and pragmatic operators, namely, assertion and hypothesis. In a second, antirealist-minded case, truth is not logically independent from justification and results in two logical systems of information and justification: AR4 and AR4¢, respectively, provided with a question-answer semantics. The latter proposes many more epistemic agents, each corresponding to a wide variety of epistemic norms. After comparing the different norms of justification involved in these logical systems, two hexagons expressing Aristotelian relations of opposition will be gathered in order to clarify how (a fragment of) pragmatic formulas can be interpreted in a fuzzy-based question-answer semantics

Norms of speech acts

This paper offers a systematic classification and characterization of speech acts and their norms. Recently, the normative approach has been applied to various speech acts, most notably to constatives. I start by showing how the work on the norms of assertion has influenced various approaches to the norms of other speech acts. I focus on the fact that various norms of assertion have different extensions, i.e., they denote different clusters of illocutions as belonging to an assertion. I argue that this has consequences for theorising about norms of other speech acts and generates certain arbitrary divisions. In the central part, I analyse two groups of speech acts. Firstly, ordinary speech acts, like predictions or retractions. Secondly, I indicate how the normative view can be extended to so-called ancillary speech acts, like presuppositions or implicatures. I end with a discussion of possible extensions of the normative approach, focusing on the debate on lying.</p

Is Truth Relevant? On the Relevance of Relevance

An assertion can be a factual claim or the expression of a value judgment. Since Hume the view that these are two incompatible types of assertions that cannot be connected by argumentation, has often been defended, and, more recently, has also been called into question. In the following paper I attempt to show that the truth both of a descriptive sentence and of a normative sentence is derived from its “practical relevance”. The demand that an assertion must be true and must be based on knowledge of the asserter is derived from the demand that an assertion must be practically relevant to the addressee. On the basis of this claim I will sketch a model of what it m

Brandom's deontic scorekeeping model and the assertive family

This paper deals with what, from a speech-act theoretical point of view, can be considered to be the \u201cillocutionary\u201d side of Robert Brandom\u2019s pragmatist framework, which regards the pragmatic significance of linguistic performances (specifically, assertional performances) characterized in terms of their effects on the normative statuses of the participants in a discursive practice. In Brandom\u2019s deontic scorekeeping model of discursive practice (which consists of ascribing, undertaking and acknowledging commitments and entitlements), all speech acts are alleged to have pragmatic significance because of their relationship with the act of asserting: here, I investigate whether the same model can be used to account for the pragmatic significance of other assertive speech acts which differ from assertion in terms of their varying degrees and modes of commitment, and I argue that it simply lacks the resources to do so. I conclude by making some general suggestions (with examples) of how an Austin-inspired conception of illocutionary force (to some extent compatible with Brandom\u2019s analysis) could be used as a basis to account for the varying degrees and modes of commitment of assertive speech acts in terms of variations in their force

Lying, speech acts, and commitment

Not every speech act can be a lie. A good definition of lying should be able to draw the right distinctions between speech acts that can be lies and speech acts that under no circumstances are lies. This paper shows that no extant account of lying is able to draw the required distinctions. It argues that a definition of lying based on the notion of ‘assertoric commitment’ can succeed where other accounts have failed. Assertoric commitment is analysed in terms of two normative components: ‘accountability’ and ‘discursive responsibility’. The resulting definition of lying draws all the desired distinctions, providing an intensionally adequate analysis of the concept of lying