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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.
Nelson  R. J. 《Synthese》1997,111(1):73-96
Quines ontological relativity is related to Tarskis theory of truth in two ways: Quine repudiates term-by-term-correspondence, as does Tarskis rule of truth; and Quines proxy argument in support of relativity finds exact formulation in Tarskis truth definition.Unfortunately, relativity is threatened by the fact that the proxy argument doesnt comply with the rule of truth (Tarskis celebrated condition (T)). Despite Quines express allegiance to (T), use of proxy schemes does not generate all of the true sentences condition (T) requires.A possible adjustment is to drop (T), retain the satisfaction definition and proxy argument, and appeal to the theory of observation and indeterminacy of reference as grounds of relativity. But as we shall see Quines theories of assent to observation sentences and of reference-learning dont square easily with his naturalism. The first attributes intentional attitudes to observers; and the second assumes a holistic context principle and a concept of individuation which do not withstand scrutiny as empirical notions. Both appear to violate Quines behavorist canon.A saving alternative is a theory of term-reference that appears in Roots of Reference and affords a return to behaviorism, and reinstatement of the proxy argument and relativity in a way compatible with Tarskis (T).  相似文献   

3.
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   

4.
Both arguments are based on the breakdown of normal criteria of identity in certain science-fictional circumstances. In one case, normal criteria would support the identity of person A with each of two other persons, B and C; and it is argued that, in the imagined circumstances, A=B and A=C have no truth value. In the other, a series or spectrum of cases is tailored to a sorites argument. At one end of the spectrum, persons A and B are such that A=B is clearly true; at the other end, A and B are such that the identity is clearly false. In between, normal criteria of identity leave the truth or falsehood of A=B undecided, and it is argued that in these circumstances A=B has no truth value.These arguments are to be understood counterfactually. My claim is that, so understood, neither establishes its conclusion. The first involves a pair of counterfactual situations that are equally possible or tied. If A=B and A=C have no truth value, a counterfactual conditional with one of them as consequent and an antecedent that is true in circumstances in which either is true should have no truth value. Intuitively, however, any such counterfactual is false. The second argument can be seen to invite an analogous response. If this is right, however, there is an important disanalogy between this and the classical paradox of the heap. If the disanalogy is only apparent, the argument shows at most that the existence of persons can be indeterminate.  相似文献   

5.
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   

6.
R. E. Jennings 《Topoi》1994,13(1):3-10
I argue that the conjunctive distribution of permissibility over or, which is a puzzling feature of free-choice permission is just one instance of a more general class of conjunctive occurrences of the word, and that these conjunctive uses are more directly explicable by the consideration that or is a descendant of oper than by reference to the disjunctive occurrences which logicalist prejudices may tempt us to regard as semantically more fundamental. I offer an account of how the disjunctive uses of or may have come about through an intermediate discourse-adverbial use of or, drawing a parallel with but, which, etymologically, is disjunctive rather than conjunctive and whose conjunctive uses seem to represent just such a discourse-adverbial application.  相似文献   

7.
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   

8.
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   

9.
Coming fromI andCl, i.e. from intuitionistic and classical propositional calculi with the substitution rule postulated, and using the sign to add a new connective there have been considered here: Grzegorozyk's logicGrz, the proof logicG and the proof-intuitionistic logicI set up correspondingly by the calculiFor any calculus we denote by the set of all formulae of the calculus and by the lattice of all logics that are the extensions of the logic of the calculus, i.e. sets of formulae containing the axioms of and closed with respect to its rules of inference. In the logiclG the sign is decoded as follows: A = (A & A). The result of placing in the formulaA before each of its subformula is denoted byTrA. The maps are defined (in the definitions of x and the decoding of is meant), by virtue of which the diagram is constructedIn this diagram the maps, x and are isomorphisms, thereforex –1 = ; and the maps and are the semilattice epimorphisms that are not commutative with lattice operation +. Besides, the given diagram is commutative, and the next equalities take place: –1 = –1 and = –1 x. The latter implies in particular that any superintuitionistic logic is a superintuitionistic fragment of some proof logic extension.  相似文献   

10.
Greg Restall 《Studia Logica》1993,52(3):381-391
A logic is said to becontraction free if the rule fromA (A B) toA B is not truth preserving. It is well known that a logic has to be contraction free for it to support a non-trivial naïve theory of sets or of truth. What is not so well known is that if there isanother contracting implication expressible in the language, the logic still cannot support such a naïve theory. A logic is said to berobustly contraction free if there is no such operator expressible in its language. We show that a large class of finitely valued logics are each not robustly contraction free, and demonstrate that some other contraction free logics fail to be robustly contraction free. Finally, the sublogics of (with the standard connectives) are shown to be robustly contraction free.  相似文献   

11.
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   

12.
This paper points out the way in which educational and communicative action (Habermas) are to be related. It is shown that earlier attempts to put Habermas ideas to use have led to a dead end because they do not realize clearly that the new basic notion introduced by Habermas, namely communicative action, is the expression of a communicative turn. It is argued that Habermas' concept expresses a radical new attempt to grasp the intersubjective character of social action. Next implications of this communicative turn for the concept of education as a social praxis are indicated. Education can be conceived of as a praxis responding to the vulnerability of a communicative self.  相似文献   

13.
In the XVIIth century the conflict which opposed the jansenists to the jesuits involved the problem of the due process in theological matter. The jesuits heralded the thesis that the infallibility of the Church has to be extended from dogmatics (quaestio iuris) to the historical facts (quaestio facti). On the opposite side Arnauld maintained that such an opinion was monstruous: also in religious matters the fact has to be proved according to the principles of a due process, and not by authority. In this article the thesis pleaded by the jansenists is considered in connection with the model of argumentative procedure offered by the Port-Royal logic.The Logique ou Art de penser (1622) by Antoine Arnauld and Pierre Nicole seems to have rediscovered the classical principles of the theory of argumentation: from the burden of proof to the idea of probable truth. But really a new model of adversary-system has been introduced into the modern mind, which is very different in concept from the topical tradition. The basic metaphor of combat, implying that the truth will prevail in the fight, is compatible with the epistemological premises of the modern logic (as the separation between fact and value). Therefore the problem of the fact-finding seems to be attracted into the area of the logic of information, and not of the theory of argumentation.
  相似文献   

14.
Two studies showed that adults' responses to questions involving the term or varied markedly depending upon the type of question presented. When presented with various objects (A's and B's) and asked to circle all things which are A or B subjects tended to circle A's as well as B's, whereas when asked to circle all the A's or B's subjects showed a relatively stronger tendency to circle one or the other. Moreover the nature of the sets of objects (As and Bs) influenced behavior as well. There was also evidence that the effects due to question wording or set type transferred.  相似文献   

15.
Richard L. Purtill 《Synthese》1971,22(3-4):431-437
In this paper I criticize Toulmin's concept of Ideals of Natural Order and his account of the role these Ideals play in scientific explanation as given in his book, Foresight and Understanding. I argue that Toulmin's account of Ideals of Natural Order as those theories taken to be self evident by scientists at a given time introduces an undesirable subjectivism into his account of scientific explanation. I argue also that the history of science, especially the recent history of microphysics, does not support Toulmin's contentions about the supposed self-evidence of the basic explanatory theories in science.  相似文献   

16.
Gilbert Scharifi 《Erkenntnis》2004,61(2-3):233-244
Mylan Engels paper (2004) is divided into two parts: a negative part, criticizing the costs of contextualism and a constructive part proposing a noncontextualist resolution of the skeptical problem. I will only address the constructive part here. The constructive part is composed of three elements: (i) a reconstruction or reformulation of the original skeptical argument, which draws on the notion of epistemic possibility (e-possibility), (ii) a distinction between two senses of knowledge (and two corresponding kinds of e-possibility): fallibilistic and infallibilistic, and (iii) an argument which tries to hoist the skeptic by their own petard, namely the closure principle (CP). As I will argue, there are two ways to understand Engels anti-skeptical argument. Only in one interpretation does the argument depend on the proposed reconstruction of the skeptical argument in terms of e-possibility. But this version of the argument is unsound. More importantly, the skeptic has a strong prima facie objection at her disposal, which applies to both interpretations of the argument. If this objection is valid, Engels argument does not hold. But once it is invalidated, his argument is superfluous.  相似文献   

17.
In "Doing Well Enough: Toward a Logic for Common Sense Morality", Paul McNamara sets out a semantics for a deontic logic which contains the operator It is supererogatory that. As well as having a binary accessibility relation on worlds, that semantics contains a relative ordering relation, . For worlds u, v and w, we say that u w v when v is at least as good as u according to the standards of w. In this paper we axiomatize logics complete over three versions of the semantics. We call the strongest of these logics DWE for Doing Well Enough.  相似文献   

18.
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   

19.
Conclusion It follows from the proved theorems that ifM =Q, (whereQ={0,q 1,q 2,...,q }) is a machine of the classM F then there exist machinesM i such thatM i(1,c)=M (q i,c) andQ i={0, 1, 2, ..., +1} (i=1, 2, ..., ).And thus, if the way in which to an initial function of content of memorycC a machine assigns a final onecC is regarded as the only essential property of the machine then we can deal with the machines of the formM ={0, 1, 2, ..., }, and processes (t) (wheret=1,c,cC) only.Such approach can simplify the problem of defining particular machines of the classM F , composing and simplifying them.Allatum est die 19 Januarii 1970  相似文献   

20.
Five different ability estimators—maximum likelihood [MLE ()], weighted likelihood [WLE ()], Bayesian modal [BME ()], expected a posteriori [EAP ()] and the standardized number-right score [Z ()]—were used as scores for conventional, multiple-choice tests. The bias, standard error and reliability of the five ability estimators were evaluated using Monte Carlo estimates of the unknown conditional means and variances of the estimators. The results indicated that ability estimates based on BME (), EAP () or WLE () were reasonably unbiased for the range of abilities corresponding to the difficulty of a test, and that their standard errors were relatively small. Also, they were as reliable as the old standby—the number-right score.  相似文献   

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