This paper focuses on postcolonial theory’s engagement with modernity. It argues that postcolonialism’s problematization of modernity is significant and has to be contended with seriously. In seeking to question the predatory universalism of western modernity, postcolonial theory aspires to open up paths for different modernities that have the promise of emancipation and liberation for all cultures and societies. But the crux of this paper is that this promise is hardly fulfilled. Using critical realism, it interrogates postcolonialism’s understanding of modernity. It (...) demonstrates that, with regard to various aspects such as the material dimension, structural conditions, binaries and dualisms, relativism, fallibilism, temporality and structure/agency, postcolonialism’s formulations are incomplete and inadequate. Ultimately, from a critical realist perspective, the non-fulfilment of postcolonialism’s initial promise has serious consequences for the subjects of the ‘Third World’ that the theory claims to represent. (shrink)
Dirac's classical electrodynamics countenances "preaccelerations" of charged particles at a time t as mathematical functions of external forces applied after the time t. These preaccelerations have been interpreted as evidence for physical retrocausation upon assuming that, in electrodynamics no less than in Newton's second law, external forces sustain an asymmetric causal relation to accelerations. And this retrocausal interpretation has just been defended against the critiques in (Grunbaum 1976), (Grunbaum and Janis, 1977 and 1978) by appeal to the formal assimilation of (...) the electrodynamic laws of motion to Newton's second law. It is argued below that this latest defense of the retrocausal interpretation is even more ill-founded than the prior ones in the literature. (shrink)
The paper briefly surveys the sentential proof-theoretic semantics for fragment of English. Then, appealing to a version of Frege’s context-principle (specified to fit type-logical grammar), a method is presented for deriving proof-theoretic meanings for sub-sentential phrases, down to lexical units (words). The sentential meaning is decomposed according to the function-argument structure as determined by the type-logical grammar. In doing so, the paper presents a novel proof-theoretic interpretation of simple type, replacing Montague’s model-theoretic type interpretation (in arbitrary Henkin models). The domains (...) of derivations are collections of derivations in the associated “dedicated” natural-deduction proof-system, and functions therein (with no appeal to models, truth-values and elements of a domain). The compositionality of the semantics is analyzed. (shrink)
The paper presents a proof-theoretic semantics (PTS) for a fragment of natural language, providing an alternative to the traditional model-theoretic (Montagovian) semantics (MTS), whereby meanings are truth-condition (in arbitrary models). Instead, meanings are taken as derivability-conditions in a dedicated natural-deduction (ND) proof-system. This semantics is effective (algorithmically decidable), adhering to the meaning as use paradigm, not suffering from several of the criticisms formulated by philosophers of language against MTS as a theory of meaning. In particular, Dummett’s manifestation argument does not (...) obtain, and assertions are always warranted, having grounds of assertion. The proof system is shown to satisfy Dummett’s harmony property, justifying the ND rules as meaning conferring. The semantics is suitable for incorporation into computational linguistics grammars, formulated in type-logical grammar. (shrink)
In the proof-theoretic semantics approach to meaning, harmony , requiring a balance between introduction-rules (I-rules) and elimination rules (E-rules) within a meaning conferring natural-deduction proof-system, is a central notion. In this paper, we consider two notions of harmony that were proposed in the literature: 1. GE-harmony , requiring a certain form of the E-rules, given the form of the I-rules. 2. Local intrinsic harmony : imposes the existence of certain transformations of derivations, known as reduction and expansion . We propose (...) a construction of the E-rules (in GE-form) from given I-rules, and prove that the constructed rules satisfy also local intrinsic harmony. The construction is based on a classification of I-rules, and constitute an implementation to Gentzen’s (and Pawitz’) remark, that E-rules can be “read off” I-rules. (shrink)
The paper proposes a semantics for contextual (i.e., Temporal and Locative) Prepositional Phrases (CPPs) like during every meeting, in the garden, when Harry met Sally and where I’m calling from. The semantics is embodied in a multi-modal extension of Combinatory Categoral Grammar (CCG). The grammar allows the strictly monotonic compositional derivation of multiple correct interpretations for “stacked” or multiple CPPs, including interpretations whose scope relations are not what would be expected on standard assumptions about surfacesyntactic command and monotonic derivation. A (...) type-hierarchy of functional modalities plays a crucial role in the specification of the fragment. (shrink)
The paper presents a generalization of pregroup, by which a freely-generated pregroup is augmented with a finite set of commuting inequations, allowing limited commutativity and cancelability. It is shown that grammars based on the commutation-augmented pregroups generate mildly context-sensitive languages. A version of Lambek’s switching lemma is established for these pregroups. Polynomial parsability and semilinearity are shown for languages generated by these grammars.
In this paper, we show how the problem of accounting for the semanticsof temporal preposition phrases (tPPs) leads us to some surprisinginsights into the semantics of temporal expressions ingeneral. Specifically, we argue that a systematic treatment of EnglishtPPs is greatly facilitated if we endow our meaning assignments with context variables, a device which allows a tPP to restrict domainsof quantification arising elsewhere in a sentence. We observe that theuse of context variables implies that tPPs can modify expressions intwo ways, and (...) we use this observation to predict the behaviour of tPPswhose complements are themselves modified by other tPPs. (shrink)
In this paper, we propose a game semantics for the (associative) Lambek calculus . Compared to the implicational fragment of intuitionistic propositional calculus, the semantics deals with two features of the logic: absence of structural rules, as well as directionality of implication. We investigate the impact of these variations of the logic on its game semantics.
A semantics with plural entitles and plural times accounts for cumulative relations between plural arguments and temporal expressions. The semantics equips nominal, verbal and sentential meanings with temporal context variables and treats temporal modifiers as temporal generalized quantifiers; cumulative conjunction, however, takes place at types lower than generalized quantifiers. The mediation of temporal context variables allows cumulative relations to percolate between an argument in a main clause and one in a temporal clause, in apparent violation of locality restrictions. Plural times (...) form a semilattice structure imposed on the set of intervals; no interaction is observed between this and the internal temporal structure of intervals. (shrink)
This paper develops an inference system for natural language within the ‘Natural Logic’ paradigm as advocated by van Benthem (1997), Sánchez (1991) and others. The system that we propose is based on the Lambek calculus and works directly on the Curry-Howard counterparts for syntactic representations of natural language, with no intermediate translation to logical formulae. The Lambek-based system we propose extends the system by Fyodorov et~al. (2003), which is based on the Ajdukiewicz/Bar-Hillel (AB) calculus Bar Hillel, (1964). This enables the (...) system to deal with new kinds of inferences, involving relative clauses, non-constituent coordination, and meaning postulates that involve complex expressions. Basing the system on the Lambek calculus leads to problems with non-normalized proof terms, which are treated by using normalization axioms. (shrink)
The paper suggests a revision of the notion of harmony, a major necessary condition in proof-theoretic semantics for a natural-deduction proof-system to qualify as meaning conferring, when moving to a bilateral proof-system. The latter considers both forces of assertion and denial as primitive, and is applied here to positive logics, lacking negation altogether. It is suggested that in addition to the balance between (positive) introduction and elimination rules traditionally imposed by harmony, a balance should be imposed also on: (i) negative (...) introduction and elimination rules, and (ii) positive and negative introduction rules. The paper suggests a proof-theoretical definition of duality (not referring to truthtables), using which double harmony is defined. The paper proves that in a doubly-harmonious system, the coordination rule, typical to bilateral systems, is admissible. (shrink)
We show that the relational semantics of the Lambek calculus, both nonassociative and associative, is also sound and complete for its extension with classical propositional logic. Then, using filtrations, we obtain the finite model property for the nonassociative Lambek calculus extended with classical propositional logic.
A detailed analysis is made of Grunbaum's claim that the Abraham-Lorentz (AL) and Dirac-Lorentz (DL) equations have no bearing on causality. It is pointed out that (a) both equations are derived from F = ma, and thus should obey the same causality conditions as Newton's law, (b) independently of what boundary conditions are imposed, non-causal behavior is always along the same straight line as the force, (c) the distinction in status between laws and boundary conditions which Grunbaum imposes is one (...) which is not always useful, especially since what is a law in one formulation of the theory can become a boundary condition in another, and thus it is argued that a complete theory must be such that laws and boundary conditions form a coherent whole, (d) the asymptotic boundary conditions that are applied are in agreement with experiment, (e) the AL equation is such that if the "effect," the acceleration as function of time, is known, then the "cause," the force, can be determined. In addition, it is noted that in the DL equation the acceleration at times later than t influences the acceleration at t. Finally, it is pointed out that electrodynamics is indeed a causal field theory, and that retrocausality is due to the transition from a field description to a particle description. (shrink)
Typed feature structures are used extensively for the specification of linguistic information in many formalisms. The subsumption relation orders TFSs by their information content. We prove that subsumption of acyclic TFSs is well founded, whereas in the presence of cycles general TFS subsumption is not well founded. We show an application of this result for parsing, where the well-foundedness of subsumption is used to guarantee termination for grammars that are off-line parsable. We define a new version of off-line parsability that (...) is less strict than the existing one; thus termination is guaranteed for parsing with a larger set of grammars. (shrink)
Unification grammars are known to be Turing-equivalent; given a grammar G and a word w, it is undecidable whether w L(G). In order to ensure decidability, several constraints on grammars, commonly known as off-line parsability (OLP), were suggested, such that the recognition problem is decidable for grammars which satisfy OLP. An open question is whether it is decidable if a given grammar satisfies OLP. In this paper we investigate various definitions of OLP and discuss their interrelations, proving that some of (...) the OLP variants are indeed undecidable. We then present a novel, decidable OLP constraint which is more liberal than the existing decidable ones. (shrink)
Cette parution est un événement. Lumière de l’Éternel est le dernier des ouvrages majeurs du rationalisme juif médiéval, ponctuant une série de tentatives de mesurer le judaïsme aux exigences de la rationalité philosophique. Son auteur, Ḥasdaï Crescas (vers 1340-1410), est un pur produit du judaïsme espagnol, philosophe et élève de grands maîtres de la tradition talmudique (notamment Nissim de Gérone, dit « le Ran »). Il fut un dirigeant de la communauté barcelonaise. L’ouvrage aurait été ac..