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1.
The aim of this note is to show (Theorem 1.6) that in each of the cases: = {, }, or {, , }, or {, , } there are uncountably many -intermediate logics which are not finitely approximable. This result together with the results known in literature allow us to conclude (Theorem 2.2) that for each : either all -intermediate logics are finitely approximate or there are uncountably many of them which lack the property.  相似文献   

2.
Aristides Baltas 《Synthese》1991,89(2):299-320
Bachelard's concept of the problématique is used in order to classify physical problems and their interrelations. This classification is effectuated along two dimensions. Along the horizontal dimension, physical problems are divided into the kinds that the different modes of physics' development define. These modes are themselves determined by the interplay among the conceptual system, the object and the experimentation transactions specific to physics. Along the vertical dimension, physical problems are classified according to the different stages of maturation they have to undergo before the process of their solution is effectively undertaken. To determine these maturation stages, the Althusserian conception of ideology is used. The interrelations between physical problems are examined through the introduction and elaboration of the notion interdependence network.It is a pleasure to thank Marcello Pera and Kostas Gavroglou for their very helpful comments and criticisms.  相似文献   

3.
In their book Entailment, Anderson and Belnap investigate the consequences of defining Lp (it is necessary that p) in system E as (pp)p. Since not all theorems are equivalent in E, this raises the question of whether there are reasonable alternative definitions of necessity in E. In this paper, it is shown that a definition of necessity in E satisfies the conditions { E Lpp, EL(pq)(LpLq), E pLp} if and only if its has the form C 1.C2 .... Cnp, where each C iis equivalent in E to either pp or ((pp)p)p.  相似文献   

4.
Edwin D. Mares 《Topoi》1994,13(1):31-36
This paper presents ConR (Conditional R), a logic of conditionals based on Anderson and Belnap's system R. A Routley-Meyer-style semantics for ConR is given for the system (the completeness of ConR over this semantics is proved in E. Mares and A. Fuhrmann, A Relevant Theory of Conditionals (unpublished MS)). Moreover, it is argued that adopting a relevant theory of conditionals will improve certain theories that utilize conditionals, i.e. Lewis' theory of causation, Lewis' dyadic deontic logic, and Chellas' dyadic deontic logic.I am of course deeply indebted to André Fuhrmann, who co-wrote the paper on which the present effort is based. Perhaps I should also thank the Social Sciences and Humanities Research Council of Canada because the original research for this project was funded by them in the form of a post-doctoral fellowship.  相似文献   

5.
I will describe the logics of a range of conditionals that behave like conditional probabilities at various levels of probabilistic support. Families of these conditionals will be characterized in terms of the rules that their members obey. I will show that for each conditional, , in a given family, there is a probabilistic support level r and a conditional probability function P such that, for all sentences C and B, CB holds just in case P[B|C]r. Thus, each conditional in a given family behaves like conditional probability above some specific support level.Chris Swoyer provided very helpful comments on drafts of this paper.  相似文献   

6.
This article argues that there is no sound basis for thinking that we have a general and strong duty to rectify disparities of wealth around the world, apart from the special case where some become wealthy by theft or fraud. The nearest thing we have to a rational morality for all has to be built on the interests of all, and they include substantial freedoms, but not substantial entitlements to others assistance. It is also pointed out that the situation of the worlds poor is not that of victims of disasters, but simply of less-developed technology, which can be repaired by full and free trade relations with others. The true savior of the worlds poor is the businessman, not the missionary. What we do need to do is strike down barriers to commerce, rather than requisition aid.  相似文献   

7.
This study examined longitudinal associations between adolescents and their friends depressive symptoms and depressogenic attributional style. Participants included 398 adolescents in grades six through eight at the outset of the study. Adolescents completed peer nominations to identify reciprocated and unreciprocated best friendships as well as measures of depressive symptoms and depressogenic attributional style at an initial time point, and again 11 months later. Results revealed that best friends reported level of depressive symptoms was prospectively associated with adolescents own depressive symptoms and with adolescents depressogenic attributional style. Moderator effects suggested that friends attributional styles were prospectively associated with adolescents own attributional styles for those involved in reciprocated friendships. Lastly, findings offered preliminary support for adolescents Time 2 depressive symptoms as a mediator of the association between friends depressive symptoms and adolescents attributional style. Findings have important implications for cognitive and interpersonal models of adolescent depression, as well as the study of peer contagion effects.  相似文献   

8.
Since the most promising path to a solution to the problem of skepticism regarding perceptual knowledge seems to rest on a sharp distinction between perceiving and inferring, I begin by clarifying and defending that distinction. Next, I discuss the chief obstacle to success by this path, the difficulty in making the required distinction between merely logical possibilities that one is mistaken and the real (Austin) or relevant (Dretske) possibilities which would exclude knowledge. I argue that this distinction cannot be drawn in the ways Austin and Dretske suggest without begging the questions at issue. Finally, I sketch and defend a more radical way of identifying relevant possibilities that is inspired by Austin's controversial suggestion of a parallel between saying I know and saying I promise: a claim of knowledge of some particular matter is relative to a context in which questions about the matter have been raised.  相似文献   

9.
Re-emergent scientific atheism bears the marks of its historical origins in the efforts of Bon-Bruevi and Jaroslavskij. The disciples of the Lenin generation use their fathers somewhat as second-level classics.  相似文献   

10.
Jim Mackenzie 《Synthese》1989,79(1):99-117
Gilbert Harman, in Logic and Reasoning (Synthese 60 (1984), 107–127) describes an unsuccessful attempt ... to develop a theory which would give logic a special role in reasoning. Here reasoning is psychological, a procedure for revising one's beliefs. In the present paper, I construe reasoning sociologically, as a process of linguistic interaction; and show how both reasoning in the psychologistic sense and logic are related to that process.  相似文献   

11.
The ω-rule     
Michael Thau 《Studia Logica》1992,51(2):241-248
We prove that all proofs in -logic (a first order logic with -rule added) in which -rule is used finitely many times can be turned into proofs in which the -rule is used at most one time. Next, we prove that the word finitely above cannot be changed by the word infinitely.  相似文献   

12.
We say that a semantical function is correlated with a syntactical function F iff for any structure A and any sentence we have A F A .It is proved that for a syntactical function F there is a semantical function correlated with F iff F preserves propositional connectives up to logical equivalence. For a semantical function there is a syntactical function F correlated with iff for any finitely axiomatizable class X the class –1X is also finitely axiomatizable (i.e. iff is continuous in model class topology).  相似文献   

13.
Voutsadakis  George 《Studia Logica》2003,74(1-2):275-311
A category theoretic generalization of the theory of algebraizable deductive systems of Blok and Pigozzi is developed. The theory of institutions of Goguen and Burstall is used to provide the underlying framework which replaces and generalizes the universal algebraic framework based on the notion of a deductive system. The notion of a term -institution is introduced first. Then the notions of quasi-equivalence, strong quasi-equivalence and deductive equivalence are defined for -institutions. Necessary and sufficient conditions are given for the quasi-equivalence and the deductive equivalence of two term -institutions, based on the relationship between their categories of theories. The results carry over without any complications to institutions, via their associated -institutions. The -institution associated with a deductive system and the institution of equational logic are examined in some detail and serve to illustrate the general theory.  相似文献   

14.
Let g E(m, n)=o mean that n is the Gödel-number of the shortest derivation from E of an equation of the form (m)=k. Hao Wang suggests that the condition for general recursiveness mn(g E(m, n)=o) can be proved constructively if one can find a speedfunction s s, with s(m) bounding the number of steps for getting a value of (m), such that mn s(m) s.t. g E(m, n)=o. This idea, he thinks, yields a constructivist notion of an effectively computable function, one that doesn't get us into a vicious circle since we intuitively know, to begin with, that certain proofs are constructive and certain functions effectively computable. This paper gives a broad possibility proof for the existence of such classes of effectively computable functions, with Wang's idea of effective computability generalized along a number of dimensions.We are grateful to an anonymous referee for Studia Logica for valuable advice leading to substantial improvements in the presentation of the main definitions and theorem.  相似文献   

15.
Lenneberg suggested that a chimpanzee's linguistic ability could be tested by presenting sentences containing two prepositional phrases joined by a conjunction. This would involve joining two semantic propositions, and thus represents a more complex test of chimpanzee syntactic competence than previously attempted. Jane, a five year-old language trained chimpanzee, was tested on her ability to both produce and comprehend sentences involving a preposition (in or behind) and a conjunction (and). The results from production and comprehension were substantially the same. Jane showed the ability to appropriately deploy and, behind and in, but displayed very little flexibility in their use. It is suggested that a chimpanzee may be able to learn some rules of syntax but is not able to be creative with that syntax.  相似文献   

16.
Peter C. Fishburn 《Synthese》1970,21(2):204-221
a–b* c–d is taken to mean that your degree of preference for a over b is less than your degree of preference for c over d. Various properties of the strength-of-preference comparison relation * are examined along with properties of simple preferences defined from *. The investigation recognizes an individual's limited ability to make precise judgments. Several utility theorems relating a–b * c–d to u(a)–u(b) are included.  相似文献   

17.
D. Greimann 《Erkenntnis》2000,52(2):213-238
The syntax of Frege's scientific language iscommonly taken to be characterized by two oddities:the representation of the intended illocutionary roleof sentences by a special sign, the judgement-stroke,and the treatment of sentences as a species ofsingular terms. In this paper, an alternative view isdefended. The main theses are: (i) the syntax ofFrege's scientific language aims at an explication ofthe logical form of judgements; (ii) thejudgement-stroke is, therefore, a truth-operator, nota pragmatic operator; (iii) in Frege's first system,` ' expresses that the circumstance is a fact, and in his second system that thetruth-value - is the True; (iv) in bothsystems, the judgement-stroke is construed as a signsui generis, not as a genuine predicate; (v) itscounterpart in natural language is the syntactic ``formof assertoric sentences', not the (redundant)truth-predicate; (vi) neither in Frege's first nor inhis second system sentences are treated as singular terms.  相似文献   

18.
The need to find an intrinsic characterization of what makes a relation between events causal arises not only in local theories of causation like Salmon's process theory but also in global approaches like Lewis' counterfactual theory. According to the localist intuition, whether a process connecting two events is causal should depend only on what goes on between the events, not on conditions that hold elsewhere in the world. If such intrinsic characterizations could be found, an identification of the causal relation in the actual world (though not in other possible worlds) with physical processes may be feasible (the a posteriori identification). I consider recent proposals made for intrinsic characterizations of causality and conclude that none of them is able to deliver the intended result.  相似文献   

19.
Building from J.L. Austin's concept of performative, this essay explores the production of subjectivity and of educational subjects by applying important work from Judith Butler on Foucault, Derrida, and as centrally illustrative, through an analysis of sex and gender. Given this analytical framework, the turn is then to queer performativity and the possibility of performative power in pedagogy. The last draws assistance from Valerie Walkerdine, Homi Bhabha and especially James Donald.  相似文献   

20.
If a certain semantic relation (which we call local consequence) is allowed to guide expectations about which rules are derivable from other rules, these expectations will not always be fulfilled, as we illustrate. An alternative semantic criterion (based on a relation we call global consequence), suggested by work of J.W. Garson, turns out to provide a much better — indeed a perfectly accurate — guide to derivability.  相似文献   

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