Several intrinsic/extrinsic distinctions amongst properties, current in the literature, are discussed and contrasted. The proponents of such distinctions tend to present them as competing, but it is suggested here that at least three of the relevant distinctions (including here that between non-relational and relational properties) arise out of separate perfectly legitimate intuitive considerations: though of course different proposed explications of the informal distinctions involved in any one case may well conflict. Special attention is paid to the question of whether a (...) single notion of property is capable of supporting the various distinctions. (shrink)

Tarski 1968 makes a move in the course of providing an account of ?definitionally equivalent? classes of algebras with a businesslike lack of fanfare and commentary, the significance of which may accordingly be lost on the casual reader. In ?1 we present this move as a response to a certain difficulty in the received account of what it is to define a function symbol (or ?operation symbol?). This difficulty, which presents itself as a minor technicality needing to be got around (...) especially for the case of symbols for zero-place functions (for ?distinguished elements?), has repercussions?not widely recognised?for the account of functional completeness in sentential logic. A similarly stark comment in Church 1956 reveals an appreciation of this difficulty, though not every subsequent author on the topic has taken the point. We fill out this side of the picture in ?2. The discussion of functional completeness in ?2 is supplemented by some remarks on what is involved in defining a connective, which have been included in an Appendix. The emphasis throughout is on conceptual clarification rather than on proving theorems, and the main body of the paper may be regarded as an elaboration on the remarks just mentioned by Tarski and Church. The Appendix (?3) is intended to be similarly clarificatory, though this time with some corrective intent, of remarks made in and about Makinson 1973. (shrink)

We consider the modal logic of non-contingency in a general setting, without making special assumptions about the accessibility relation. The basic logic in this setting is axiomatized, and some of its extensions are discussed, with special attention to the expressive weakness of the language whose sole modal primitive is non-contingency , by comparison with the usual language based on necessity.

This paper considers the question: what becomes of the notion of a logic as a way of codifying valid arguments when the customary assumption is dropped that the premisses and conclusions of these arguments are statements from some single language? An elegant treatment of the notion of a logic, when this assumption is in force, is that provided by Dana Scott's theory of consequence relations; this treatment is appropriately generalized in the present paper to the case where we do not (...) make this assumption of linguistic homogeneity. Several applications of the resulting concept of a heterogeneous logic are suggested, but the main emphasis is on the formal development. One topic touched on is a certain contrast between the boolean and the intensional sentence-connectives in this more general setting. (shrink)

Hegel was one of the philosophers, who seemingly paid only little attention to the conceptual problems of aetiology. The paper deals especially with those parts of his work, in which Hegel sheds light particularly on these problems. It examines a evaluates Hegel's conception of interconnection between entities such as reality, essence, necessity, appearance and causality . A special attention is paid to the question of "causa sui" as inherently related to the problem of mutual causation. The paper shows many methodological (...) dangers as well as the lessons, we can still draw from Hegel's aetiological reflections. (shrink)

If what is known need not be closed under logical consequence, then a distinction arises between something's being known to be the case (by a specific agent) and its following from something known (to that subject). When each of these notions is represented by a sentence operator, we get a bimodal logic in which to explore the relations between the two notions.

This paper is about a support information management system for a wind power producer having an energy storage system and participating in a day-ahead electricity market. Energy storage can play not only a leading role in mitigation of the effect of uncertainty faced by a WP producer, but also allow for conversion of wind energy into electric energy to be stored and then released at favourable hours. This storage provides capability for arbitrage, allowing an increase on profit of a WP (...) producer, but must be supported by a convenient problem formulation. The formulation proposed for the support information management system is based on an approach of stochasticity written as a mixed integer linear programming problem. WP and market prices are considered as stochastic processes represented by a set of scenarios. The charging/discharging of the ESS are considered dependent on scenarios of market prices and on scenarios of WP. The effectiveness of the proposed formulation is tested by comparison of case studies using data from the Iberian Electricity Market. The comparison is in favour of the proposed consideration of stochasticity. (shrink)

SummaryIf you know you can recognise positive instances of a property, can you use this knowledge so as to be able to recognise also its negative instances? This is the question to be adressed.

The adverse reaction to Hempel's 'ravens paradox' embodied in giving it that description is compared with the usual reaction of experimental subjects to the Wason selection task.

A purported axiomatization, by P. Gärdenfors, of intuitionistic propositional logic is shown to be incomplete, and that the mistaken claim to completeness is seen to result from carelessness in the choice of primitive logical vocabulary. This leads to a consideration of various ways of conceiving the distinction between primitive and defined vocabularies, along with the bearing of these differences on such matters as are discussed in connection with Gärdenfors.

The purpose of this paper is to assess Profet’s (1992) and others’ hypothesis that nausea and vomiting in pregnancy (NVP) is adaptive. A number of studies have found an association between NVP and a decreased risk for early fetal loss (<20 weeks). It is assumed that the adaptive benefits of improved survivorship associated with NVP outweigh the minimal nutritional consequences. However, in populations that experience marginal levels of nutrition, NVP may have important nutritional consequences. To test these potential consequences, a (...) study on NVP, nutritional status, and pregnancy outcome was conducted among Turkana pastoralists, who experience seasonal and chronic nutritional stress. Interviews and anthropometric assessments were conducted on 68 pregnant Turkana women of Kenya during a 1993–1994 field season. The results from the case study suggest that women who experience NVP do encounter nutritional consequences in the later stages of pregnancy and are more likely to experience poor pregnancy outcomes. These results suggest that NVP may not be adaptive in all environmental settings, particularly among marginally nourished populations. (shrink)

We illustrate, with three examples, the interaction between boolean and modal connectives by looking at the role of truth-functional reasoning in the provision of completeness proofs for normal modal logics. The first example (§ 1) is of a logic (more accurately: range of logics) which is incomplete in the sense of being determined by no class of Kripke frames, where the incompleteness is entirely due to the lack of boolean negation amongst the underlying non-modal connectives. The second example (§ 2) (...) focusses on the breakdown, in the absence of boolean disjunction, of the usual canonical model argument for the logic of dense Kripke frames, though a proof of incompleteness with respect to the Kripke semantics is not offered. An alternative semantic account is developed, in terms of which a completeness proof can be given, and this is used (§ 3) in the discussion of the third example, a bimodal logic which is, as with the first example, provably incomplete in terms of the Kripke semantics, the incompleteness being due to the lack of disjunction (as a primitive or defined boolean connective). (shrink)

The literature on critical thinking (CT) in counselling and therapy generally posits higher quality outcomes when CT is applied in therapeutic treatment. We critically examine support for the claim that CT improves clinical outcomes. The purported effects of CT are first identified by arguments in favour of using CT in therapeutic treatment, both in terms of its general efficacy and with regard to its applicability in professional counselling. We then underscore limitations in the current literature, highlighting mainly a gap between (...) theory and practice. Overall, our results suggest that available evidence provides primarily inferential, rather than direct, support for the claim that CT positively influences therapy outcomes. We close the paper by proposing research questions to guide further empirical investigation. (shrink)

This essay is a critical theological and pastoral study of the Working Document of the Second African Synod. The article engages the articles in the document which deal with the theme of reconciliation. This essay begins by exploring the Christological and ecclesiological foundations for an African theology of reconciliation as found in the working document. While engaging the significant aspects of the working document which relate to articulating an African theology of reconciliation, this essay shows the limitations of the document (...) in its historical and cultural analysis of the situation in Africa. Drawing from a phenomenological hermeneutical engagement with African history, cultural grammar, and Christ-centered African Christian imagination, the essay widens the scope of theological engagement with the task of reconciliation in Africa. It does a theological aesthetics of reconciliation in Africa, by integrating diverse cultural, ontological, and Christological symbols within the African world on vital participation and vital union. Through the inculturation of vital participation as analogous to Trinitarian Communion, the essay shows how the Church in Africa can deal with the ever-revolving cycle of violence, conflicts, and divisions in the churches and political institutions which have all hampered the mission of building relationship and God's kingdom in Africa. The essay concludes by recommending four pastoral approaches through which the Catholic Church in Africa can be both a reconciled community and an instrument for reconciliation in Africa. (shrink)