So close no matter how far: counterfactuals in history of science and the inevitability/contingency controversy

This paper has a twofold purpose. First, it aims at highlighting one difference (albeit in degree and not in kind) in how counterfactuals work in general history, on the one hand, and in history of the natural sciences, on the other hand. As we show, both in general history and in history of science good counterfactual narratives need to be plausible, where plausibility is construed as appropriate continuity of both the antecedent and the consequent of the counterfactual with what we know about the world. However, in general history it is often possible to imagine a consequent dramatically different from the actual historical development, and yet plausible; in history of science, due to plausibility concerns, imagining a consequent far removed from the results of actual science seems more complicated. The second aim of the paper is to assess whether and to what degree counterfactual histories of science can advance the cause of the so-called “contingency thesis,” namely, the claim that history of science might have followed a path leading to alternative, non-equivalent theories, as successful as the ones that we currently embrace. We distinguish various versions of the contingency thesis and argue that counterfactual histories of science support weak versions of the thesis.

     

First steps toward an understanding of procedural fairness

In four experiments, we tested whether 20‐month‐old infants are sensitive to violations of procedural impartiality. Participants were shown videos in which help was provided in two different ways. A main character provided help to two other agents either impartially, by helping them at the same time, or in a biased way, by helping one agent almost immediately while the other after a longer delay. Infants looked reliably longer at the biased than at the unbiased help scenarios despite the fact that in both scenarios help was provided to each beneficiary. This suggests that human infants can attend to departures from impartiality and, in their second year, they already show an initial understanding of procedural fairness.     

Repeatability of mae-geri-keage in traditional karate: a three-dimensional analysis with black-belt karateka

In karate, performance also depends on a correct body shape, and the repeatability of standardized movements conditions the effectiveness of techniques. The execution of mae-geri-keage (frontal snap kick) was studied in 13 karateka (1st-5th dan). The 3D trajectories of 13 body landmarks were analyzed by an optoelectronic instrument while each karateka performed 10 repetitions of the movement. For each karateka and repetition, the standard deviations of the spatial coordinates x, y, z for each landmark were computed. A total standard deviation of the single participant was also calculated. Two experienced karateka performed with the best repeatability (smaller standard deviation) while executing the studied kick. Generally, the best repeatability was observed in the horizontal plane. The lower variability was observed in hips and head. Ankle and knee of the dominant limb had the worse. The method could detect athletes particularly gifted for the discipline. Moreover, it could help in the identification of those parts of body that do not repeat the movement with the desired precision.     

Illusory 3-D rotation induced by dynamic image shading

Observers' perceptions of the three-dimensional structure of smoothly curved surfaces defined by patterns of image shading were investigated under varying conditions of illumination. In five experiments, observers judged the global orientation and the motion of the simulated surfaces from both static and dynamic patterns of image shading. We found that perceptual performance was more accurate with static than with dynamic displays. Dynamic displays evoked systematic biases in perceptual performance when the surface and the illumination source were simulated as rotating in opposite directions. In these conditions, the surface was incorrectly perceived as rotating in the same direction as the illumination source. Conversely, the orientation of the simulated surfaces was perceived correctly when the frames making up the apparent-motion sequences of the dynamic displays were presented as static images. In Experiment 6, moreover, the results obtained with the computer-generated displays were replicated with solid objects.     

Conceptual development and conversational understanding

Children's understanding of the implications of conversation can influence their responses on tasks designed to measure conceptual development. These responses are in keeping with developmental changes in the ability to recognize and resolve ambiguity in communicative contexts, as shown, for example, in children's ability to compute "scalar implicatures". Examining steps children take to overcome difficulties in processing the relevant features of tasks and in correctly interpreting task instructions promise to illuminate mechanisms of conceptual development. We review recent research in this area, focussing on early knowledge of the appearance-reality distinction and knowledge of cosmological concepts.     

On Modal μ-Calculus and Non-Well-Founded Set Theory

A finitary characterization for non-well-founded sets with finite transitive closure is established in terms of a greatest fixpoint formula of the modal -calculus. This generalizes the standard result in the literature where a finitary modal characterization is provided only for wellfounded sets with finite transitive closure. The proof relies on the concept of automaton, leading then to new interlinks between automata theory and non-well-founded sets.     

Representation of two geometric features of the environment in the domestic chick (<Emphasis Type="Italic">Gallus gallus</Emphasis>)

We report experiments based on a novel test in domestic chicks (Gallus gallus), designed to examine the encoding of two different geometric features of an enclosed environment: relative lengths of the walls and amplitude of the corners. Chicks were trained to search for a food reward located in one corner of a parallelogram-shaped enclosure. Between trials, chicks were passively disoriented and the enclosure was rotated, making reorientation possible only on the basis of the internal spatial structure of the enclosure. In order to reorient, chicks could rely on two sources of information: the relative lengths of the walls of the enclosure (associated to their left-right sense order) and the angles subtended by walls at corners. Chicks learned the task choosing equally often the reinforced corner and its rotational equivalent. Results of tests carried out in novel enclosures, the shapes of which were chosen ad hoc (1) to induce reorientation based only on the ratio of walls lengths plus sense (rectangular enclosure), or (2) to induce reorientation based only on corner angles (rhombus-shaped enclosure), suggested that chicks encoded both features of the environment. In a third test, in which chicks faced a conflict between these geometric features (mirror parallelogram-shaped enclosure), reorientation seemed to depend on the salience of corner angles. These results shed light on the elements of the environmental geometry which control spatial reorientation, and broaden the knowledge on the geometric representation of space in animals.     

The time course of attentional focusing in dyslexic and normally reading children

A cue size procedure was used to evaluate the time course of visuo-spatial attention in dyslexic and normally reading children. When a stimulus target is presented inside a large cue vs a small cue the identification time is slower. In the present study two cue-target delays (100 and 500 ms) were used. Results showed a slower time course of attentional focusing in dyslexics vs normal readers. Indeed, dyslexics exhibited no cue size effect at a shorter cue-target delay (100 ms), while it was present at a longer cue-target delay (500 ms). In contrast, a cue size effect was found at both cue-target delays in normally reading children. These results further support the hypothesis of sluggish automatic focusing of visual attention in dyslexics. This impairment could be a consequence of a general magnocellular deficit demonstrated previously in dyslexics.     

Substance P antagonists: meet the new drugs,same as the old drugs? Insights from transgenic animal models

Antidepressants that primarily target the reuptake of monoamines have been highly successful treatments. However, therapies with these drugs still have several drawbacks, namely severe side effects, delays in the onset of action, and a significant percentage of non-responders. Recently, non-peptidic antagonists of the neurokinin 1 receptor, or substance P antagonists, have emerged as a novel class of drugs with antidepressant efficacy that is comparable to current drugs, but a potentially reduced side effect profile. This review summarizes the pre-clinical evidence derived from pharmacological and transgenic animal studies that suggests an important role for the substance P/neurokinin 1 system in anxiety and depression. Also, potential mechanisms by which substance P antagonists may produce their therapeutic effects are discussed.