We report two studies on the effect of implicitly versus explicitly conveying affirmation and denial problems about conditionals. Recently Evans and Handley (1999) and Schroyens et al. (1999b, 2000b) showed that implicit referencing elicits matching bias: Fewer determinate inferences are made, when the categorical premise (e.g., B) mismatches the conditional's referred clause (e.g., A). Also, the effect of implicit affirmation (B affirms not-A) is larger than the effect of implicit denial (B denies A). Schroyens et al. hypothesised that this interaction (...) is due to uncertainty in the case-wise affirmation of the contrast class of negated elements involved in implicit affirmations. In Experiment 1 we tested this hypothesis by manipulating the set size of the conditional clauses. The results confirm that binary sets, where the contrast class is a singleton, eliminate the differential effect of implicit affirmation and denial. With non-binary sets the interaction is not modulated by the scope of the contrast class (3, 5, 9 elements). Experiment 2 further investigated the role of contrast classes by using class inclusion to construct implicit affirmations (Mammal vs Mammal or Monkey) and implicit denial (No-Mammal vs Mammal or Monkey), in addition to the standard implicit problems mediated by contrast-class inclusion [(No-)Mammal/No-Mammal; Reptile; Snake). Findings indicate that class inclusion (Mammal/Monkey; Reptile/ Snake) only marginally affects performance, and is independent of the type of problem. This would suggest that the implicitness problem-type interaction is dependent on constructing contrast classes. However, the experiment failed to replicate the interaction, even on the subset of problems repeating the abstract letter/number format of Experiment 1. Moreover, with the natural binary set-sizes (vowels/consonants) the implicitness effect was eliminated entirely. (shrink)

Two types of truth table tasks are used investigating mental representations of conditionals: a possibilities-based and a truth-based one. In possibilities tasks, participants indicate whether a situation is possible or impossible according to the conditional rule. In truth tasks participants evaluate whether a situation makes the rule true or false, or is irrelevant with respect to the truth of the rule. Comparing the two-option version of the possibilities task with the truth task in Experiment 1, the possibilities task yields logical (...) answer patterns whereas the truth task yields defective patterns. Adding the irrelevant option to the possibilities task in Experiment 2 leads to a considerable amount of defective patterns in the possibilities task, but still to more logical patterns in the possibilities task than in the truth task. Experiment 3 shows that directionality matters since rule-to-situation tasks yield more logical answer patterns than do situation-to-rule tasks. We conclude that both task types are not comparable as such since wording, number of options and directionality influence the results. (shrink)

"Under the auspices of the International Union of Psychological Science.".

The essays appearing in these two volumes are based on Keynote and State-of-the-Art Lectures delivered at the XXVth International Congress of Psychology, in Brussels, July 1992. The Brussels Congress was the latest in a series of conferences which are organized at regular intervals under the auspices of the International Union of Psychological Science, the main international organization in the field of Scientific Psychology. The first of those meetings took place in Paris in 1889. An important function of the International Congresses (...) is to promote communication between different specializations in Psychology. Speakers were therefore asked to present lectures and discussions in their own fields of study, in a way that would be accessible to fellow psychologists active in other fields. State-of-the-Art lecturers were specifically asked to prepare a tutorial review on a topic which, in the view of the Program Committee, had recently given rise to particularly important developments. These contributions are included in Volume Two. Keynote lecturers were left free to address whatever subject they felt was of greatest interest. The chapters in Volume 1 are preceded by the Presidential Address by Mark R. Rosenzweig. (shrink)

MATERIALISTS claim that in principle mentality could be accounted for entirely by properties of matter. They must, of course, clarify, as far as possible, the precise scope of the concept "properties of matter." According to materialists there exists only one type of "substance" in the universe, namely matter. Sophisticated experimental and theoretical analyses have led contemporary physicists to interpret known material entities as being composed of two classes of elementary particles, namely quarks and leptons and constituents of interaction fields that (...) mediate interactions between some or all of the elementary particles and which comprise photons, gluons, intermediate bosons and gravitons. For instance, protons and neutrons are composed--by hypothesis--of quarks, while electrons are probably the most familiar leptons. Whether any analyzed and postulated elementary particles and constituents of interaction fields are "ultimate" components of matter can never be known. It remains always possible that more basic subcomponents of known components will be discovered. This has happened repeatedly throughout the history of physics. Hence, what physicists understand by the "physical properties" of the basic components of matter must always remain expressed in terms of usually intricate hypothetico-deductive theories which are tentative and fallible. Contemporary relativistic quantum mechanics of elementary particles and of interaction fields provide typical examples of such hypothetico-deductive theories relating to present known basic components of matter. (shrink)

SummaryExtremism in the environment‐versus innateness controversy in the behavioural sciences and in human sociobiology is being examined. Genetic effects can be severely modified or overruled by environmental factors, but may, nevertheless, be important. Dawkins' view that we are survival machines programmed to subserve selfish genes seems untenable and is a root of racialism. It is also argued that morality is compatible with mixed genetic and environmental control of brains via existing biological machinery.

We present a meta-analytic review on the processing of negations in conditional reasoning about affirmation problems (Modus Ponens: “MP”, Affirmation of the Consequent “AC”) and denial problems (Denial of the Antecedent “DA”, and Modus Tollens “MT”). Findings correct previous generalisations about the phenomena. First, the effects of negation in the part of the conditional about which an inference is made, are not constrained to denial problems. These inferential-negation effects are also observed on AC. Second, there generally are reliable effects of (...) a negation in the clause referred to by the categorical premise, and these referred-negation effects are constrained to the logically fallacious AC and DA inferences. All findings are presented and discussed in relation to contemporary mental model (MM) and mental logic (ML) theories. It is argued that a double-negation elimination hypothesis provides a sufficient explanation of inferential-negation effects within both MM theory and ML theory, if the latter is extended by a validating search for counter examples. Both MM and ML theories adhere to a processing scheme that allows them to incorporate an account of referred-negation effects based on the thesis that counter-example frequency is modulated by the scope of a contrast class delineated by a false affirmative. We conclude that MM and ML theories provide adequate processing schemes to accommodate for the explanatory hypotheses, at least in principle. In practice, both approaches remain equivocal as regards the connectivity and interactivity with long-term memory knowledge invoked in generating, manipulating, and testing the mental representations of negative state of affairs. (shrink)

At Phaedo 59b Echecrates asks Phaedo who was present on the day when Socrates drank the hemlock in prison. Various Athenians are named , then various foreigners , but when Echecrates subsequently asks if two other foreigners, Aristippus and Cleombrotus, were present, Phaedo replies that they were said to be in Aegina . After this fleeting reference to Cleombrotus, Plato does not mention him again in the Phaedo or any other dialogue; and yet in later antiquity a certain Cleombrotus of (...) Ambracia rose to fame in connection with the Phaedo. Callimachus is our earliest source for the anecdote which immortalized the Ambracian : Επας ‘Ἥλιε αρε’ Κλεμβρτος μβρακιτης λατ' φ' Ψηλο τεεος ες δην, ζιον οδν δν θαντου κακν, λλ Πλτωνος ν τ περ Ψυς γρμμ' ναλεζμενος. (shrink)

This edition, the first modern one in English, introduces undergraduates and more advanced students to the therapeutic possibilities of Seneca's Stoic philosophy. The short treatises De otio and De brevitate vitae balance each other by representing different but complementary aspects of Senecan philosophy: in De otio, one's duty to the 'active' life, in De brevitate vitae, one's duty to oneself in reclaiming life from the impositions made upon the self. The provocative Senecan message is to promote introspection in life, and (...) to suggest the benefits of an inner existence of the personal. In addition to its literary and linguistic emphasis, this edition tries to advertize the means by which Seneca conveys the attractions of his therapeutic 'philosophy'. (shrink)

The Four-Colour Theorem (4CT) proof, presented to the mathematical community in a pair of papers by Appel and Haken in the late 1970's, provoked a series of philosophical debates. Many conceptual points of these disputes still require some elucidation. After a brief presentation of the main ideas of Appel and Haken’s procedure for the proof and a reconstruction of Thomas Tymoczko’s argument for the novelty of 4CT’s proof, we shall formulate some questions regarding the connections between the points raised by (...) Tymoczko and some Wittgensteinian topics in the philosophy of mathematics such as the importance of the surveyability as a criterion for distinguishing mathematical proofs from empirical experiments. Our aim is to show that the “characteristic Wittgensteinian invention” (Mühlhölzer 2006) – the strong distinction between proofs and experiments – can shed some light in the conceptual confusions surrounding the Four-Colour Theorem. (shrink)

This paper examines the creation of independent agencies within the EU, such as the European Environment Agency and the European Central Bank. Majone and others have argued the case for European regulatory agencies. Such agencies can provide for continuity, expertise, accountability and effective authority – in short, an institutionalisation of responsibility. Against this optimism, I argue that a dilemma of institutional design naturally arises from the agencies’ situation in the EU. On the one side, we risk creating powerful agencies that (...) institutionalise monomania– that is, agencies that single-mindedly and all-too-effectively pursue narrow agendas, inadequately checked by other bodies. On the other, we are also likely to encounter relatively impotent agencies which institutionalise schizophrenia– that is, agencies that must scout around for audience and support, and hence are unable to act effectively. (shrink)