Insight into a logical relation

Two experiments are reported which aimed to investigate factors affecting the gain of insight into the logical relation of implication. In the first experiment, subjects had to make a series of inferences about either a conditional sentence or a quantified sentence, both of which had the same underlying logical form. Under one condition the sentences had to be proved true, and under another condition, false. Proving a sentence false facilitated gain of insight, but the linguistic form of the sentence exerted no significant effect on the main dependent variable. In the second experiment, implication was not expressed as a sentence but was inherent in the structure of the task. The experimental material differed in complexity and allowed the cognitive load imposed on the subject to be varied. Results suggested that insight was not all-or-none. It was spontaneously gained when the material was simple, but temporarily lost when it was complex.     

Spatial correspondence and relation correspondence: grouping factors that influence perception of the Ternus display

We cite two different perceptual-correspondence principles whose emphasis can help to disambiguate the otherwise ambiguous Ternus display in apparent movement (a display that can alternately be seen in one of two possible configurations). One of these principles is spatial correspondence, which emphasizes the maintenance of similar stimulus elements in given locations over time. The other principle is relation correspondence, which emphasizes the maintenance of the inter-organization of stimulus elements across frames. Each of four experiments reported here made use of a different stimulus feature (eg element color or element texture) to emphasize these different correspondence principles in Ternus displays. As predicted, an emphasis upon spatial correspondence resulted in an increase in reports of element movement compared to a featureless control condition. Emphasis on relation correspondence resulted in an increase in reports of group movement. Extensions and limitations of the use of these principles to explain apparent movement are discussed.     

Display-control arrangement correspondence and logical recoding in the Hedge and Marsh reversal of the Simon effect

When left and right keypresses are made to stimuli in left and right locations, and stimulus location is irrelevant to the task, responses are typically faster when stimulus location corresponds with response location than when it does not (the Simon effect). This effect reverses when the relevant stimulus-response mapping is incompatible, with responses being slower when stimulus and response locations correspond (the Hedge and Marsh reversal). Simon et al. (Acta Psychol. 47 (1981) 63) reported an exception to the Hedge and Marsh reversal for a situation in which the relevant stimulus dimension was the color of a centered visual stimulus and the irrelevant location information was left or right tone location. In contrast, similar experiments have found a reversal of the Simon effect for tone location when relevant visual locations were mapped incompatibly to responses. We conducted four experiments to investigate this discrepancy. Both results were replicated. With an incompatible mapping, irrelevant tone location showed a small reverse Simon effect when the relevant visual dimension was physical location but not when the color of a centered stimulus or the direction in which an arrow pointed conveyed the visual location information. The reversal occurred in a more standard Hedge and Marsh task in which the irrelevant dimension was location of the colored stimulus, but only when the response keys were visibly labeled. Several of the results suggest that display-control arrangement correspondence is the primary cause of the Hedge and Marsh reversal, with logical recoding playing only a secondary role.     

The logical study of science

The relation between logic and philosophy of science, often taken for granted, is in fact problematic. Although current fashionable criticisms of the usefulness of logic are usually mistaken, there are indeed difficulties which should be taken seriously — having to do, amongst other things, with different scientific mentalities in the two disciplines (section 1). Nevertheless, logic is, or should be, a vital part of the theory of science. To make this clear, the bulk of this paper is devoted to the key notion of a scientific theory in a logical perspective. First, various formal explications of this notion are reviewed (section 2), then their further logical theory is discussed (section 3). In the absence of grand inspiring programs like those of Klein in mathematics or Hilbert in metamathematics, this preparatory ground-work is the best one can do here. The paper ends on a philosophical note, discussing applicability and merits of the formal approach to the study of science (section 4).I would like to thank David Pearce and Veikko Rantala for their helpful comments.     

Symmetry and transitivity assumptions about a nonspecified logical relation

Twenty-five subjects were presented with eight problems involving a non-specified relation, devoid of its concrete content. This relation was signified by the symbol (--), thus logically precluding any knowledge about the properties of the relation. The problems were so designed that the truth evaluation of their solution statements reflected assumptions about the symmetry and transitivity properties of the relation. Six subjects assumed that the relation was both symmetrical and transitive, and 12 subjects assumed that it was symmetrical only. When these same 18 subjects were presented with problems which lent themselves to only one of these assumptions, all assumed that the relation was symmetrical rather than transitive. The remaining seven subjects made neither of these two assumptions in any of the problems. Examples of logical relations, given as part of the problems, and varying in their properties of symmetry and transitivity, had no effect on the subjects' assumptions. It is proposed that symmetrical and transitive relations are conceptual good figures which predisposed subjects to perceive the nonspecified relation as symmetrical or as transitive. The stronger tendency towards symmetry assumptions than towards transitivity assumptions suggests that symmetrical relations are better figures than transitive relations.     

A logical expression of reasoning

A non-monotonic logic, the Logic of Plausible Reasoning (LPR), capable of coping with the demands of what we call complex reasoning, is introduced. It is argued that creative complex reasoning is the way of reasoning required in many instances of scientific thought, professional practice and common life decision taking. For managing the simultaneous consideration of multiple scenarios inherent in these activities, two new modalities, weak and strong plausibility, are introduced as part of the Logic of Plausible Deduction (LPD), a deductive logic specially designed to serve as the monotonic support for LPR. Axiomatics and semantics for LPD, together with a completeness proof, are provided. Once LPD has been given, LPR may be defined via a concept of extension over LPD. Although the construction of LPR extensions is first presented in standard style, for the sake of comparison with existing non-monotonic formalisms, alternative more elegant and intuitive ways for constructing non-monotonic LPR extensions are also given and proofs of their equivalence are presented.     

Management of hyperactive children through correspondence training procedures: A preliminary study

This study examined the clinical effects of correspondence training procedures in the management of three hyperactive boys between the ages of seven and 10 years. Two subjects were intervened with the “reinforcement of corresponding reports” procedure: reports about the inhibition of hyperactivity (inattention and overactivity) were reinforced only if they corresponded with the actual inhibition of hyperactivity. The “reinforcement set up contingent upon promises” procedure was used with the third subject: the reinforcer was set up (or displayed) contingent on the patient's promises about the inhibition of hyperactivity in the immediate future, and delivered contingent upon fulfillment of the promise (actual inhibition of hyperactivity). These interventions were programmed in a multipie baseline design across two subjects and a multiple baseline design across two behaviors. A changing-criterion design was also used with all subjects: the nonoccurrence of hyperactivity had to be observed across a pre-established criterion level for the actual delivery of the reinforcer. Consistently higher levels of correspondence occurred during treatment, relative to baseline observations. The results also demonstrated the generalization and maintenance of treatment effects. The use of correspondence training as a potential alternative in the development of hyperactive children's self-control is discussed.     

Reassessing logical hylomorphism and the demarcation of logical constants

The paper investigates the propriety of applying the form versus matter distinction to arguments and to logic in general. Its main point is that many of the currently pervasive views on form and matter with respect to logic rest on several substantive and even contentious assumptions which are nevertheless uncritically accepted. Indeed, many of the issues raised by the application of this distinction to arguments seem to be related to a questionable combination of different presuppositions and expectations; this holds in particular of the vexed issue of demarcating the class of logical constants. I begin with a characterization of currently widespread views on form and matter in logic, which I refer to as ‘logical hylomorphism as we know it’—LHAWKI, for short—and argue that the hylomorphism underlying LHAWKI is mereological. Next, I sketch an overview of the historical developments leading from Aristotelian, non-mereological metaphysical hylomorphism to mereological logical hylomorphism (LHAWKI). I conclude with a reassessment of the prospects for the combination of hylomorphism and logic, arguing in particular that LHAWKI is not the only and certainly not the most suitable version of logical hylomorphism. In particular, this implies that the project of demarcating the class of logical constants as a means to define the scope and nature of logic rests on highly problematic assumptions.     

A logical calculus with descriptions

Journal of Philosophical Logic -     

A plea for logical objects

An account of validity that makes what is invalid conditional on how many individuals there are is what I call a conditional account of validity. Here I defend conditional accounts against a criticism derived from Etchemendy’s well-known criticism of the model-theoretic analysis of validity. The criticism is essentially that knowledge of the size of the universe is non-logical and so by making knowledge of the extension of validity depend on knowledge of how many individuals there are, conditional accounts fail to reflect that the former knowledge is basic, i.e., independent of knowledge derived from other sciences. Appealing to Russell’s pre-Principia logic, I defend conditional accounts against this criticism by sketching a rationale for thinking that there are infinitely many logical objects.     

A geometric interpretation of logical formulae

Summary The aim of this paper is to give a geometric interpretation of quantifiers in the intutionistic predicate calculus. We obtain it treating formulae withn free variables as functions withn arguments which run over an abstract set whereas the values of functions are open subsets of a suitable topological space.     

A defense of contingent logical truths

A formula is a contingent logical truth when it is true in every model M but, for some model M, false at some world of M. We argue that there are such truths, given the logic of actuality. Our argument turns on defending Tarski’s definition of truth and logical truth, extended so as to apply to modal languages with an actuality operator. We argue that this extension is the philosophically proper account of validity. We counter recent arguments to the contrary presented in Hanson’s ‘Actuality, Necessity, and Logical Truth’ (Philos Stud 130:437–459, 2006).     

A logical formalization of the OCC theory of emotions

In this paper, we provide a logical formalization of the emotion triggering process and of its relationship with mental attitudes, as described in Ortony, Clore, and Collins’s theory. We argue that modal logics are particularly adapted to represent agents’ mental attitudes and to reason about them, and use a specific modal logic that we call Logic of Emotions in order to provide logical definitions of all but two of their 22 emotions. While these definitions may be subject to debate, we show that they allow to reason about emotions and to draw interesting conclusions from the theory.     

A corrective note on O'Donohue and Szymanski's study of logical analysis and REBT's use of empirical hypothesis testing as well as logical analysis

This article acknowledges the contribution of O'Donohue and Szymanski's study showing that the logical analysis of irrational beliefs that rational emotive behavior therapy (REBT) favors may be more effective than the empirical hypothesis testing that cognitive therapy (CT) favors. It points out, however, that logical analysis and empirical hypothesis testing include overlapping concepts and procedures. REBT, though favoring logical analysis, actually uses empirical hypothesis testing too.     

A dialogical route to logical pluralism

This paper argues that adopting a particular dialogical account of logical consequence quite directly gives rise to an interesting form of logical pluralism, the form of pluralism in question arising out of the requirement that deductive proofs be explanatory.