This article will engage with the current disasters in Japan from the perspective of semiotic anthropology. Disaster seems to produce two moments of the sign: signa naturalia and signa data. The translation of the sign mirrors the architectonic of the signified of disaster, which is mediated by a token-level instantiation of signifiers that initially appears either absent or in excess. The conceptualization of disaster as a zero sign, that is, unlimited possibility, allows an investigation of “a struggle of interpretants” in (...) stipulating the interpretative grounds of the signified amid regenerative processes of social regularity. It is this very exact moment of translation that the sustained continuity reveals its culture-specific “deep social grammar.” Disaster or “shaking grounds” has the presenting effect of cultural palimpsests. These unearthed palimpsests enable a heightened metasemiotic awareness of institutional and ideological regimentations, on the one hand, and token-level recontexualizations, assimilations, and hybridizations of the depository of signs in society in the post-disaster contexts, on the other. The article concludes with an attempt to synthesize Peircean semeiotics and Saussurean semiology by assessing the two distinct modes of semiosis, culture and trauma, upon a sudden threat of the experience of discontinuity. (shrink)

The present contribution shows that a Hilbert-style axiomatization for dynamic logic of relation changers is complete for the standard Kripke semantics not by a well-known rewriting technique but by the idea of an auxiliary semantics studied by van Benthem and Wang et al. A key insight of our auxiliary semantics for dynamic logic of relation changers can be described as: “relation changers are bounded morphisms.” Moreover, we demonstrate that this semantic insight can be used to provide a modular cut-free labelled (...) sequent calculus for the logic in the sense that our calculus can be regarded as a natural expansion of a labelled sequent calculus of iteration-free propositional dynamic logic. (shrink)

In this paper, we propose a learning method for an agent to interact with other agents effectively. This method, MULA-C, improves efficiency of the learning, by clustering agents, and influences the learning experience of one agent to other agents which belong to the same cluster. Similarity among agents is evaluated by similarity among Q-values of agents. We give the detail explanation of learning method of MULA-C, and present the result of experiments which shows the effectiveness of MULA-C.

This article attempts to answer why some countries experience the recurrence of civil war and others do not. One of the most significant differences between civil war onset and its recurrence is that the latter has once experienced termination of civil war, while the former has not. To find the cause of recurrence, this article examines how different war termination types influence the duration of post-civil war peace. Duration analysis of the civil wars between 1944 and 1999 shows that military (...) victory, supported by peacekeeping operations or power-sharing arrangements, leads to the most durable peace in a post-civil war country. Contrary to the accepted wisdom, negotiated peace settlement, even when supported by peacekeeping operations or power-sharing arrangements, is not positively related to post-conflict peace. (shrink)

We extend natural deduction for first-order logic (FOL) by introducing diagrams as components of formal proofs. From the viewpoint of FOL, we regard a diagram as a deductively closed conjunction of certain FOL formulas. On the basis of this observation, we first investigate basic heterogeneous logic (HL) wherein heterogeneous inference rules are defined in the styles of conjunction introduction and elimination rules of FOL. By examining what is a detour in our heterogeneous proofs, we discuss that an elimination-introduction pair of (...) rules constitutes a redex in our HL, which is opposite the usual redex in FOL. In terms of the notion of a redex, we prove the normalization theorem for HL, and we give a characterization of the structure of heterogeneous proofs. Every normal proof in our HL consists of applications of introduction rules followed by applications of elimination rules, which is also opposite the usual form of normal proofs in FOL. Thereafter, we extend the basic HL by extending the heterogeneous rule in the style of general elimination rules to include a wider range of heterogeneous systems. (shrink)

We establish the “contraction-elimination theorem” which means that if a sequent Γ A is provable in the implicational fragment of the Gentzen's sequent calculus LK and if it satisfies a certain condition on the number of the occurrences of propositional variables, then it is provable without the right contraction rule. By this theorem, we get the following.1. If an implicational formula A is a theorem of classical logic and is not a theorem of intuitionistic logic, then there is a propositional (...) variable which occurs at least once positively and at least twice negatively in A → a) → a).2. If an implicational formula A is a theorem of intuitionistic logic and is not a theorem of BCK-logic, then there is a propositional variable which occurs at least twice positively and at least once negatively in A → a → b).We prove the contraction-elimination theorem by a fully syntactical method, which has some analogy with Gentzen's cut-elimination. (shrink)

Proof-theoretical notions and techniques, developed on the basis of sentential/symbolic representations of formal proofs, are applied to Euler diagrams. A translation of an Euler diagrammatic system into a natural deduction system is given, and the soundness and faithfulness of the translation are proved. Some consequences of the translation are discussed in view of the notion of free ride, which is mainly discussed in the literature of cognitive science as an account of inferential efficacy of diagrams. The translation enables us to (...) formalize and analyze free ride in terms of proof theory. The notion of normal form of Euler diagrammatic proofs is investigated, and a normalization theorem is proved. Some consequences of the theorem are further discussed: in particular, an analysis of the structure of normal diagrammatic proofs; a diagrammatic counterpart of the usual subformula property; and a characterization of diagrammatic proofs compared with natural deduction proofs. (shrink)

One of the traditional applications of Euler diagrams is as a representation or counterpart of the usual set-theoretical models of given sentences. However, Euler diagrams have recently been investigated as the counterparts of logical formulas, which constitute formal proofs. Euler diagrams are rigorously defined as syntactic objects, and their inference systems, which are equivalent to some symbolic logical systems, are formalized. Based on this observation, we investigate both counter-model construction and proof-construction in the framework of Euler diagrams. We introduce the (...) notion of “counter-diagrammatic proof”, which shows the invalidity of a given inference, and which is defined as a syntactic manipulation of diagrams of the same sort as inference rules to construct proofs. Thus, in our Euler diagrammatic framework, the completeness theorem can be formalized in terms of the existence of a diagrammatic proof or a counter-diagrammatic proof. (shrink)

9th and 10th Nov. 2013 at Kyoto University. Organizers: Takeshi Sato and Shunsuke Sugimoto.

The Southern Journal of Philosophy, EarlyView.

Let ℸ be the set of Gödel numbers Gn of function symbols f such that PRA ⊢ and let γ be the function such that equation imageWe prove: The r. e. set ℸ is m-complete; the function γ is not primitive recursive in any class of functions {f1, f2, ⃛} so long as each fi has a recursive upper bound. This implies that γ is not primitive recursive in ℸ although it is recursive in ℸ.

Detection of genuine altruists could be a solution to the problem of subtle cheating. Brown et al. (Evol Psychol 1:42–69, 2003) found that humans could detect altruists using nonverbal cues. However, their experiments can be improved upon in several ways, and further investigation is needed to determine whether altruist-detection abilities are human universals. In our experiment, we used video clips of natural conversations as the stimulus. We asked a sample of Japanese undergraduates to rate their own level of altruism and (...) then to estimate the videotaped targets’ altruism using the same scale. The perceivers were able to estimate the targets’ altruism levels accurately. Perceivers’ altruism score did not affect their ability to discriminate between altruists and non-altruists. Perceivers’ impressions of the altruist and non-altruist targets were also found to be different. Coding of nonverbal behavior of the targets revealed that altruists exhibited more “felt smiles” than non-altruists, which also supports the results of the previous study. (shrink)

To investigate the relationship between logical reasoning and majority voting, we introduce logic with groups Lg in the style of Gentzen’s sequent calculus, where every sequent is indexed by a group of individuals. We also introduce the set-theoretical semantics of Lg, where every formula is interpreted as a certain closed set of groups whose members accept that formula. We present the cut-elimination theorem, and the soundness and semantic completeness theorems of Lg. Then, introducing an inference rule representing majority voting to (...) Lg, we introduce logic with majority voting Lv. Formalizing the discursive paradox in judgment aggregation theory, we show that Lv is inconsistent. Based on the premise-based and conclusion-based approaches to avoid the paradox, we introduce logic with majority voting for axioms Lva, where majority voting is applied only to non-logical axioms as premises to construct a proof in Lg, and logic with majority voting for conclusions Lvc, where majority voting is applied only to the conclusion of a proof in Lg. We show that both Lva and Lvc are syntactically complete and consistent, and we construct collective judgments based on the provability in Lva and Lvc, respectively. Then, we discuss how these systems avoid the discursive paradox. (shrink)

We introduce several restricted versions of the structural rules in the implicational fragment of Gentzen's sequent calculus LJ. For example, we permit the applications of a structural rule only if its principal formula is an implication. We investigate cut-eliminability and theorem-equivalence among various combinations of them. The results include new cut-elimination theorems for the implicational fragments of the following logics: relevant logic E, strict implication S4, and their neighbors (e.g., E-W and S4-W); BCI-logic, BCK-logic, relevant logic R, and the intuitionistic (...) logic. (shrink)

The logic CD is an intermediate logic which exactly corresponds to the Kripke models with constant domains. It is known that the logic CD has a Gentzen-type formulation called LD and rules are replaced by the corresponding intuitionistic rules) and that the cut-elimination theorem does not hold for LD. In this paper we present a modification of LD and prove the cut-elimination theorem for it. Moreover we prove a “weak” version of cut-elimination theorem for LD, saying that all “cuts” except (...) some special forms can be eliminated from a proof in LD. From these cut-elimination theorems we obtain some corollaries on syntactical properties of CD: fragments collapsing into intuitionistic logic. Harrop disjunction and existence properties, and a fact on the number of logical symbols in the axiom of CD. (shrink)

The most famous chapter of Montesquieu’s _ The Spirit of the Laws _ (1748), Book XI, Chapter 6, 'On the constitution of England,' was an important i nspiration to the creators of modern constitutions, to which they often referred. However, as a result of scholarly focus on the political institutions discussed in this book, Montesquieu’s economic analysis has been woefully neglected. In order to correct this scholarly imbalance, this paper will elucidate the essential significance of Montesquieu’s comparison between the constitution (...) of modern England and that of ancient Rome in Book XI of _ The Spirit of the Laws _ ; inextricable relationship between military and political institutions on the one hand, and the transfer and distribution of wealth on the other. To argue this point, this paper will focus on Montesquieu’s other writings in the same year and shortly after the publication of _ The Spirit of the Laws _ : the revised edition in 1748 of _ The Considerations on the Causes of the Greatness of t... _. (shrink)

The semilattice relevant logics ∪R, ∪T, ∪RW, and ∪TW are defined by semilattice models in which conjunction and disjunction are interpreted in a natural way. For each of them, there is a cut-free labelled sequent calculus with plural succedents . We prove that these systems are equivalent, with respect to provable formulas, to the restricted systems with single succedents . Moreover, using this equivalence, we give a new Hilbert-style axiomatizations for ∪R and ∪T and prove equivalence between two semantics for (...) the contractionless logics ∪RW and ∪TW. (shrink)

This paper is an attempt to explain why Russell abandoned the ontology of propositions, mind-independent complex entities that are possible objects of judgements. I argue that he did so not because of any decisive argument but because he found it better to endorse the existential account of truth, according to which a judgement is true if and only if there exists (or in his view subsists) a corresponding fact. In order to endorse this account, he had examined various theories of (...) judgement before he adopted the multiple-relation theory of judgement, the most feasible way he then had of espousing it. I also attempt to explain why he preferred the existential account of truth. (shrink)