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1.
A reduction rule is introduced as a transformation of proof figures in implicational classical logic. Proof figures are represented as typed terms in a -calculus with a new constant P (()). It is shown that all terms with the same type are equivalent with respect to -reduction augmented by this P-reduction rule. Hence all the proofs of the same implicational formula are equivalent. It is also shown that strong normalization fails for P-reduction. Weak normalization is shown for P-reduction with another reduction rule which simplifies of (( ) ) into an atomic type.This work was partially supported by a Grant-in-Aid for General Scientific Research No. 05680276 of the Ministry of Education, Science and Culture, Japan and by Japan Society for the Promotion of Science. Hiroakira Ono  相似文献   

2.
Praca ta zostaa wykonana pod kierunkiem prof. drJerzego Supeckiego. Jej szczególny przypadek dotyczcyn-wartociowego rachunku zda o jednej wartoci wyrónionej by referowany w Warszawie na zjedzie Grupy Logiki Instytutu Filozofii i Socjologii PAN. Streszczenie tego referatu [5] zostao wydrukowane w Sprawozdaniach Wydziau Nauk Spoecznych PAN.Allatum est die 19 Aprilis 1963  相似文献   

3.
Patricia Williams made a number of claims concerning the methods and practise of cladistic analysis and classification. Her argument rests upon the distinction of two kinds of hierarchy: a divisional hierarchy depicting evolutionary descent and the Linnean hierarchy describing taxonomic groups in a classification. Williams goes on to outline five problems with cladistics that lead her to the conclusion that systematists should eliminate cladism as a school of biological taxonomy and to replace it either with something that is philosophically coherent or to replace it with pure methodology, untainted by theory (Williams 1992, 151). Williams makes a number of points which she feels collectively add up to insurmountable problems for cladistics. We examine Williams' views concerning the two hierarchies and consider what cladists currently understand about the status of ancestors. We will demonstrate that Williams has seriously misunderstood many modern commentators on this subject and all of her five persistent problems are derivable from this misunderstanding.

Nelson (1989, 67).

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4.
Ron McClamrock 《Erkenntnis》1995,42(1):107-112
In The Levels of Selection (Brandon, 1984), Robert Brandon provides a suggestive but ultimately unsuccessful attempt to use the probabilistic notion ofscreening off in providing a schema for dealing with an aspect of the units of selection question in the philosophy of biology. I characterize that failure, and suggest a revision and expansion of Brandon's account which addresses its key shortcoming.  相似文献   

5.
This paper is devoted to showing certain connections between normal modal logics and those strictly regular modal logics which have as a theorem. We extend some results of E. J. Lemmon (cf. [66]). In particular we prove that the lattice of the strictly regular modal logics with the axiom is isomorphic to the lattice of the normal modal logics.The results in this paper were reported at Logic Colloquium '87 in Granada.  相似文献   

6.
The issue of this paper is cultural plurality as a problem for public, general education and for (personal) identity. In order to examine this question, one needs to be clear about the meaning of the concepts of general education, on the one hand, and cultural diversity on the other. In the first section, we will fix the meaning of these concepts. A conceptual distinction between cultural diversity and cultural pluralism will be introduced. In the second section, it will be argued that open pluralism can only be maintained if there is a basic common culture apart from the cultural diversity that pluralism affirms. Therefore, there is yet an indispensable role for general education in an open, pluralistic society. In the third section we will look at two metaphors that give an opposite significance to the relation between identity and diversity: the conversational metaphor and the food metaphor mishmash. The final section expands on the conversational metaphor by way of an exposition of Ricoeur's hermeneutics of the self. It supplies us with a promising concept of identity that is not in complete opposition to diversity.  相似文献   

7.
Sági  Gábor 《Studia Logica》2002,72(2):265-284
We will study the class RSA of -dimensional representable substitution algebras. RSA is a sub-reduct of the class of representable cylindric: algebras, and it was an open problem in Andréka [1] that whether RSA can be finitely axiomatized. We will show, that the answer is positive. More concretely, we will prove, that RSA is a finitely axiomatizable quasi-variety. The generated variety is also described. We note that RSA is the algebraic counterpart of a certain proportional multimodal logic and it is related to a natural fragment of first order logic, as well.  相似文献   

8.
This article aims at elucidating the logic of Arist. SE 22, 178b36–179a10 and, in particular, of the sophism labelled "Third Man" discussed in it. I suggest that neither the sophistic Walking Man argument, proposed by ancient commentators, nor the Aristotelian Third Man of the , suggested by modern interpreters, can be identified with the fallacious argument Aristotle presents and solves in the passage. I propose an alternative reconstruction of the Third Man sophism and argue that an explanation of the lines regarding the identity of Coriscus and Coriscus the musician (178b39–179a3) is indispensable for its correct understanding, since they hint at another sophism in some important aspects analogous. Finally, I show that two contradictions concerning spotted by scholars in the passage are only apparent and can be dissolved once the assumption that the anti-Platonic Third Man argument is at stake here is discarded, and once the passage is read in the light of its agonistic context.  相似文献   

9.
In [2] a semantics for implication is offered that makes use of stories — sets of sentences assembled under various constraints. Sentences are evaluated at an actual world and in each member of a set of stories. A sentence B is true in a story s just when B s. A implies B iff for all stories and the actual world, whenever A is true, B is true. In this article the first-order language of [2] is extended by the addition of the operator the story ... says that ..., as in The story Flashman among the Redskins says that Flashman met Sitting Bull. The resulting language is shown to be sound and complete.  相似文献   

10.
In Descartes's philosophy, communicating scientific and philosophical truth does not represent a problem that can be traced back to humanistic rhetoric, meant as the art of persuasion. Descartes states his belief in the eloquence of reason: a clear, precise, and adequately expressed thought cannot fail to convince the listener. This is the measure of the distance between the level of truth and the level of opinion. However, the moment of confrontation with the public is also the very moment when the truth of the new knowledge enters into conflict with other, different conceptions. Education and history influence communication with the result that the distinction between intellectual conviction and persuasion becomes less straightforward. Rational eloquence, as Descartes is well aware, must be articulated in such a way as to avoid any possible language equivocation and to adopt exposition strategies ensuring effective access to readers. The aim of this paper is to illustrate some aspects of this tension as expressed by the writer Descartes with reference to a number of texts (from the Regulae to the Meditationes) that were essential for the elaboration and dissemination of his philosophy.  相似文献   

11.
Fred Kersten 《Human Studies》1997,20(4):391-412
The purpose of this lecture is to celebrate the memory of Aron Gurwitsch by examining and enlarging the domain of phenomenological clarification of some elements of what Gurwitsch called the logic of reality. Chief among those elements are the nature of the taken-for-grantedness of our existential belief, the difference between presentive and non-presentive indices of reality and the ground for the self-illumination of the world of working.  相似文献   

12.
Jig-Chuen Lee 《Synthese》1986,68(2):213-223
In a recent paper Causal Asymmetry, Douglas Ehring has proposed an intriguing solution to the vexing problem of causal asymmetry. The aim of this paper is to show that his theory is not satisfactory. Moreover, the examples that I use in showing the defect of Ehring's theory also indicate that the counterfactual analysis of causation has a problem that cannot be remedied by Marshall Swain's suggested refinement of the counterfactual analysis of causation in Causation and Distinct Events.  相似文献   

13.
Steven Horst 《Synthese》1995,104(1):123-145
It has recently been claimed (1) that mental states such as beliefs are theoretical entities and (2) that they are therefore, in principle, subject to theoretical elimination if intentional psychology were to be supplanted by a psychology not employing mentalistic notions. Debate over these two issues is seriously hampered by the fact that the key terms theoretical and belief are ambiguous. This article argues that there is only one sense of theoretical that is of use to the eliminativist, and in this sense some kinds of belief (dispositional states, infra-conscious states and the Freudian unconscious) are indeed theoretical and hence possible candidates for elimination, while others (consciously occurring thoughts like judgements and perceptualGestalten) are not theoretical and hence not candidates for elimination.  相似文献   

14.
We consider the problem of axiomatizing various natural successor logics for 2-dimensional integral spacetime. We provide axiomatizations in monomodal and multimodal languages, and prove completeness theorems. We also establish that the irreflexive successor logic in the standard modal language (i.e. the language containing and ) is not finitely axiomatizable.  相似文献   

15.
In Mandel'tam's writing, artistic creativity is described as based on the indispensable yet contradictory modes of compliance and deviation. The artist, by his artistic nature, must be an obedient disciple to the tradition that inspires him, and, at the same time, a violator who renders what inspires him in an individual form. Thus, art implies iterability through novelty. In the totalitarian state, this double nature of art acquires a sinister context and brings the artist to an unavoidable conflict with the state. He has a choice between a servile compliance with the state's command and artistic independence. If the artist complies, he loses his ingenuity; if, on the other hand, he has the courage to break away from the established order, his fate is martyrdom. The criteria of truth and falsehood, the issue of loyalty, of compromise and collaboration or resistance become most relevant. Such words as outcast or non-contemporary acquire the meaning of non-collaborationist or enemy of the people. In the totalitarian state a genuine artist is viewed as a law-breaker, and his art leads him to crime. The notions of compliance and deviation cease being merely aesthetic terms and assume in Mandel'tam's poetry complex, subtle and tragic overtones.I would like to express my gratitude to John Barnstead, Thomas Blakeley, James Doull, Elena Glazov-Corrigan, Gregory Glazov, Leonard Kazdan, Peter Kussmaul, Malcolm Ross, Detlev Steffen, and Ieva Vitins for their valuable criticism, suggestions, and revisions of my English.  相似文献   

16.
A coefficient of association is described for a contingency table containing data classified into two sets of ordered categories. Within each of the two sets the number of categories or the number of cases in each category need not be the same.=+1 for perfect positive association and has an expectation of 0 for chance association. In many cases also has –1 as a lower limit. The limitations of Kendall's a and b and Stuart's c are discussed, as is the identity of these coefficients to' under certain conditions. Computational procedure for is given.  相似文献   

17.
The notion of monadic three-valued ukasiewicz algebras was introduced by L. Monteiro ([12], [14]) as a generalization of monadic Boolean algebras. A. Monteiro ([9], [10]) and later L. Monteiro and L. Gonzalez Coppola [17] obtained a method for the construction of a three-valued ukasiewicz algebra from a monadic Boolea algebra. In this note we give the construction of a monadic three-valued ukasiewicz algebra from a Boolean algebra B where we have defined two quantification operations and * such that *x=*x (where *x=-*-x). In this case we shall say that and * commutes. If B is finite and is an existential quantifier over B, we shall show how to obtain all the existential quantifiers * which commute with .Taking into account R. Mayet [3] we also construct a monadic three-valued ukasiewicz algebra from a monadic Boolean algebra B and a monadic ideal I of B. The most essential results of the present paper will be submitted to the XXXIX Annual Meeting of the Unión Matemática Argentina (October 1989, Rosario, Argentina).  相似文献   

18.
Summary An attempt was made to specify the relationship between perceived surface lightness and perceived illumination under the stimulus conditions where different combinations of albedo and illuminance gave 10 approximately equal-luminance levels of a test field (TF) on three different (black-, gray- and white-appearing) backgrounds. Two types of category judgments for TF-lightness and overall illumination were made on the total of 94 TFs by 5 Ss. The results indicated that under the condition where achromatic surface colors appear, the perceptual scission which produces two different perceptual dimensions (lightness and perceived illumination) from one sort of stimulation (luminance) was clearly observed. The relation between the two judgments was consistent with the lightness-illumination invariance hypothesis: As lightness judgments (A) changed from darker to lighter, illumination judgments (I) shifted form brighter to dimmer, the sum of A and I being kept nearly invariant for a given luminance of the TF; the psychological relationship between lightness and illumination, A+I, changed as a linear function of the photometric combination of albedo and illuminance, log A+log I. It was also found that the albedo of the background was an important factor determining the extent of perceptual scission between lightness and illumination.  相似文献   

19.
Bulgarian philosophical life is particularly poor and fruitless. As well as in all communist countries the development of Bulgarian Marxism-Leninism was marked by some very sharp controversies between dogmatics and revisionists. Bulgarian Orthodoxes are particularly militant and intolerant and on the contrary, revisionists are in reality very moderate and rather conservative. Therefore the deviations are insignificant and the degree of the destalinization is very small.  相似文献   

20.
After indicating a number of points of agreement with the argument 0eveloped by Kenneth Strike in his article Liberalism, Citizenship and the Private Interest in Schooling, this article identifies and explores a number of queries and criticisms which arise in relation to that argument. These queries and criticisms relate especially to the nature and extent of the expansiveness involved in Strike's conception of public or common educational influence, and to the implications and justification of the claim that private educational interests enjoy a greater salience and recognition on Strike's view of public or common educational influence than on some alternative views.  相似文献   

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