Some Syntactic Approaches to the Handling of Inconsistent Knowledge Bases: A Comparative Study Part 1: The Flat Case

This paper presents and discusses several methods for reasoning from inconsistent knowledge bases. A so-called argued consequence relation, taking into account the existence of consistent arguments in favour of a conclusion and the absence of consistent arguments in favour of its contrary, is particularly investigated. Flat knowledge bases, i.e., without any priority between their elements, are studied under different inconsistency-tolerant consequence relations, namely the so-called argumentative, free, universal, existential, cardinality-based, and paraconsistent consequence relations. The syntax-sensitivity of these consequence relations is studied. A companion paper is devoted to the case where priorities exist between the pieces of information in the knowledge base.     

Relevance

Relevance is a triadic relation between an item, an outcome or goal, and a situation. Causal relevance consists in an item's ability to help produce an outcome in a situation. Epistemic relevance, a distinct concept, consists in the ability of a piece of information (or a speech act communicating or requesting a piece of information) to help achieve an epistemic goal in a situation. It has this ability when it can be ineliminably combined with other at least potentially accurate information to achieve the goal. The relevance of a conversational contribution, premiss relevance and conclusion relevance are species of epistemic relevance thus defined. The conception of premiss relevance which results provides a basis for determining when the various arguments ad called fallacies of relevance are indeed irrelevant. In particular, an ad verecundiam appeal is irrelevant if the authority cited lacks expertise in a cognitive domain to which the conclusion belongs, the authority does not exercise its expertise in coming to endorse the conclusion, or the conclusion does not belong to a cognitive domain; otherwise the ad verecundiam is relevant.     

Classical rhetorical topics and contemporary historical discourse

This paper suggests a specific contribution of contemporary history and philosophy of science to the theory of history. The pragmatic in the technical sense of analysis of use and user aspects of scientific discourse, and the pragmatist, in the sense of a focus on utility as canon, dimensions of modern philosophy of science illumine the structure of historical inquiry. Simply put, the structure of writing produced by the historical discipline is argumentative. Further, the nature of the historical argumentative strategies is best described by reference to classical rhetorical, to topical modes of argument.     

Discrimination of multidimensional geometrical figures by chickens: categorization and pattern-learning

Japanese bantam hens were trained to discriminate between geometrical figures varying along four integral dimensions. Only one dimension predicted food: selections of sharp-cornered figures were reinforced, while selections of rounded figures were not. In experiment 1, hens were subsequently trained to discriminate between nine figure pairs in a simultaneous discrimination task. Because single pairs contained multiple redundant cues, whereas the relevant dimension was obvious only across stimulus pairs, the results revealed effects of both generalization and reversal learning. Accordingly, learning speed was enhanced for later discriminations. Experiment 2 tested the hens’ transfer performance to unknown pairs, following experience of 9 or 18 figure pairs. Four of seven hens showed reliable transfer after experience with 9 figures, but only three showed transfer after experience with 18 figures, indicating lower transfer with higher number of stimulus pairs learned. In experiment 3, hens were trained to discriminate 27 figure pairs. Discrimination ratios further decreased and the groups of pairs differed significantly in their ratios of discrimination. Individual hens’ pecking behaviour was analysed in relation to each dimension of single figures and in relation to relative differences in the levels of dimensions between paired figures. Hens were shown to be oriented towards irrelevant information and more towards relational and configurational than elemental and dimensional aspects. The results are discussed in the biological context of individual recognition in chickens’ dominance hierarchies, in which we suppose that chickens identify individual flock mates by representation of their visual pattern rather than by single characteristics. Received: 18 September 1998 / Accepted after revision: 23 December 1998     

Development and crossmodal transfer of contextual control of emergent stimulus relations

Six normally capable adults first learned three conditional relations in each of two prospective equivalence classes via match-to-sample training with figures as conditional (sample) and discriminative (comparison) stimuli. Then one trained conditional relation in each prospective class was brought under the control of contextual stimuli, two dictated nonsense syllables. Test performances indicated the emergence of untrained conditional relations, and therefore two equivalence classes, that were conditional on the contextual stimuli. These tests involved untrained combinations of contextual stimuli and stimuli in conditional relations, suggesting that the contextual stimuli functioned independently to control conditional relations rather than forming compound stimuli with samples and comparisons in training. Next, two novel figures were made equivalent to each of the original dictated contextual stimuli by match-to-sample training and testing. On subsequent tests, all subjects demonstrated transfer of conditional control of untrained conditional relations from the original auditory contextual stimuli to equivalent visual stimuli. These outcomes further supported the conclusion that the contextual stimuli exerted true conditional control over conditional relations in the equivalence classes and were not merely elements of compound stimuli.     

Brightness contrast: a reinterpretation of compound cue and combined cue experiments with pigeons.

A group of three pigeons was trained on a 4-ply multiple schedule: a green color and a vertical line superimposed upon an achromatic background as positive stimuli, and a red color and a horizontal line on an achromatic background as negative stimuli. The pigeons were tested with the vertical line superimposed upon different achromatic background intensities, then with the vertical line superimposed upon different green background intensities, and finally with the vertical line and its training achromatic backgfound attenuated (and unattenuated) by a neutral density filter. The gradients peaked at the luminance of the achromatic background used during training and at the equivalent luminance for the green background when it was substituted for the achromatic background. The brightness contrast, not the background luminance, was the critical variable as the neutral density filter attenuated both the line and the background equally, leaving brightness contrast unchanged; there was no response decrement to this attenuated stimulus. Two other groups of three pigeons showed that they attended to line orientation as well as to brightness contrast. The brightness contrast hypothesis was extended to explain results of attention experiments and combined cue experiments which have used line stimuli in combinations with different backgrounds.     

Psychometric Evaluation of an Alternate Scoring for the Remote Associates Test

The Remote Associates Test (RAT; Mednick, 1962; Mednick & Mednick, 1967) is a commonly employed test of creative convergent thinking. The RAT is scored with a dichotomous scoring, scoring correct answers as 1 and all other answers as 0. Based on recent research into the information processing underlying RAT performance, we argued that the dichotomous scoring may lead to a loss of potentially relevant information. Thus, we proposed an alternate scoring based on semantic similarity between the answer given by the participant and the correct solution using Latent Semantic Analysis (LSA; Landauer & Dumais, 1997). We evaluate the psychometric properties of the alternate LSA scoring and found evidence of construct validity for the LSA scoring which was comparable to findings for the standard scoring, but not better as we would have expected. Thus, our expectations that LSA-based scoring of the RAT counteracts potential information loss were not met. However, LSA based scorings appear to be a promising alternative for hardly solvable RAT items. We conducted additional analyses comparing different RAT item types with regard to their validity as well as evaluating the information uniquely contained in the LSA scoring. Implications of all finding for existing research using RAT items are discussed.     

The Role of Rhetoric in Rational Argumentation

The structure of this discussion will be tripartite. First it will set out a way of distinguishing between rhetoric and strictly rational argumentation. Next it will consider some of the ramifications of this proposed way of looking at the matter – in particular what its implications are for rationality and for rhetoric, respectively. Finally it examines how this perspective bears on the project of philosophizing. The paper's ultimate aim, accordingly, is to consider what light such an analysis can shed upon philosophy and philosophizing.     

Rules for argumentation in dialogues

In this article it is pointed out what kind of rules for communication and argumentation are required in order to make it possible to resolve disputes in an orderly way. In section 2, Gricean maxims and Searlean speech act conditions are integrated in such a way that five general rules for communication can be formulated. In section 3, starting from Lewis's definition of convention, it is argued that the interactional effect of accepting is conventionally linked with the complex communicative act complex of argumentation. In section 4, the rules for argumentation are placed in a dialogical perspective.     

Formal aspects of Legal reasoning

This paper discusses the functions of deductive justification in ideal reconstructions of judicial reasoning. It departs from the point of judicial reasoning: explaining and justifying the judicial decision. It argues that deductive validity is not enough for good judicial argument. On the other hand, deductive justification is necessary, not only for easy cases but for hard cases as well. It draws some consequences for the concept of jumps in legal reasoning and for the traditional distinction between internal and external justification.