We studied patients with left visual extinction following right hemisphere damage in a simple manual reaction time task using brief visual stimuli. With unilateral lateralized stimuli the patients showed a high proportion of unwanted, reflex-like saccades to either side of stimulation. In contrast, with bilateral stimuli there was an overall decrease in the proportion of unwanted saccades, and the vast majority of them were directed toward the ipsilesional side. The implications of these results for the Findlay & Walker model are (...) discussed. (shrink)
This study examined the hypothesis that religiosity would be differentially related to six types of adolescent prosocial behaviour, and that these relations would be mediated by the prosocial value of kindness. Self?report data were collected from 142 high school students (63 per cent female; 91 per cent White; M age?=?16.8, S?=?.80). Religiosity was a significant positive predictor of kindness, as well as compliant, anonymous and altruistic prosocial behaviour, but not public, dire and emotional prosocial behaviour. Associations between religiosity and both (...) compliant and altruistic prosocial behaviours were mediated by kindness. Direct and indirect paths were found between religiosity and anonymous prosocial behaviour. Thus, partial support was found for the mediational hypothesis. Discussion focused on the utility of distinguishing among different types of prosocial behaviours and on the role of religion and values in promoting moral education. (shrink)
There are three concerns regarding Rachlin's altruism model. First, proximal causal mechanisms such as those identified by cognitive neuroscientists and behavioral neuropharmacologists are not emphasized. Second, there is a lack of clear testable hypotheses. And third, extreme forms of altruism are emphasized rather than common forms. We focus on an overarching theme – proximal mechanisms of individual differences in altruism.
I never met Gian-Carlo Rota but I have often made references to his writings on the philosophy of mathematics, sometimes agreeing, sometimes disagreeing. In this paper I will discuss his views concerning four questions: the existence of mathematical objects, definition in mathematics, the notion of proof, the relation of philosophy of mathematics to mathematics.
What is quantum mechanics about? The most natural way to interpret quantum mechanics realistically as a theory about the world might seem to be what is called wave function ontology: the view according to which the wave function mathematically represents in a complete way fundamentally all there is in the world. Erwin Schroedinger was one of the first proponents of such a view, but he dismissed it after he realized it led to macroscopic superpositions (if the wave function evolves in (...) time according to the equations that has his name). The Many-Worlds interpretation1 accepts the existence of such macroscopic superpositions but takes it that they can never be observed. Superposed objects and superposed observers split together in different worlds of the type of the one we appear to live in. For these who, like Schroedinger, think that macroscopic superpositions are a problem, the common wisdom is that there are two alternative views: "Either the wave function, as given by the Schroedinger equation, is not everything, or is not right" [Bell 1987]. The deBroglie-Bohm theory, now commonly known as Bohmian Mechanics, takes the first option: the description provided by a Schroedinger-evolving wave function is supplemented by the information provided by the configuration of the particles. The second possibility consists in assuming that, while the wave function provides the complete description of the system, its temporal evolution is not given by the Schroedinger equation. Rather, the usual Schroedinger evolution is interrupted by random and sudden "collapses". The most promising theory of this kind is the GRW theory, named after the scientists that developed it: Gian Carlo Ghirardi, Alberto Rimini and Tullio Weber.. It seems tempting to think that in GRW we can take the wave function ontologically seriously and avoid the problem of macroscopic superpositions just allowing for quantum jumps. In this paper we will argue that such "bare" wave function ontology is not possible, neither for GRW nor for any other quantum theory: quantum mechanics cannot be about the wave function simpliciter. That is, we need more structure than the one provided by the wave function. As a response, quantum theories about the wave function can be supplemented with structure, without taking it as an additional ontology. We argue in reply that such "dressed-up" versions of wave function ontology are not sensible, since they compromise the acceptability of the theory as a satisfactory fundamental physical theory. Therefore we maintain that: 1- Strictly speaking, it is not possible to interpret quantum theories as theories about the wave function; 2- Even if the wave function is supplemented by additional non-ontological structures, there are reasons not to take the resulting theory seriously. Moreover, we will argue that any of the traditional responses to the measurement problem of quantum mechanics (Bohmian mechanics, GRW and Many-Worlds), contrarily to what commonly believed, share a common structure. That is, we maintain that: 3- All quantum theories should be regarded as theories in which physical objects are constituted by a primitive ontology. The primitive ontology is mathematically represented in the theory by a mathematical entity in three-dimensional space, or space-time. (shrink)
In the 1960s molecular population geneticists used Monte Carlo experiments to evaluate particular diffusion equation models. In this paper I examine the nature of this comparative evaluation and argue for three claims: first, Monte Carlo experiments are genuine experiments: second, Monte Carlo experiments can provide an important meansfor evaluating the adequacy of highly idealized theoretical models; and, third, the evaluation of the computational adequacy of a diffusion model with Monte Carlo experiments is significantlydifferent from the evaluation (...) of the emperical adequacy of the same diffusion model. (shrink)
The essay examines both the dances and the dance notation of renowned nineteenth century choreographer Carlo Blasis. It looks in detail at Blasis major treatise The Code of Terpsichore in an effort to evaluate how Blasis linked a science of movement to a conception of the body oriented around the prevailing aesthetics informing all of the fine arts. Identifying Blasis as both a philosopher and a mechanist, this essay analyzes his approach to teaching basic ballet vocabulary, and in particular (...) the arabesque. Whereas Kleist, with his Marionettentheater, proposes the puppet as a figure of grace, located somewhere between animal and doll, Blasis brings together the movement science of mechanics and the descriptive theory of grace (as mimesis) in a poetics of the arabesque, a synthesis of elevation and evanescence, which we see when we conjure up pictures of nineteenth century Romantic ballet. (shrink)
Exploring how people represent natural categories is a key step toward developing a better understanding of how people learn, form memories, and make decisions. Much research on categorization has focused on artificial categories that are created in the laboratory, since studying natural categories defined on high-dimensional stimuli such as images is methodologically challenging. Recent work has produced methods for identifying these representations from observed behavior, such as reverse correlation (RC). We compare RC against an alternative method for inferring the structure (...) of natural categories called Markov chain Monte Carlo with People (MCMCP). Based on an algorithm used in computer science and statistics, MCMCP provides a way to sample from the set of stimuli associated with a natural category. We apply MCMCP and RC to the problem of recovering natural categories that correspond to two kinds of facial affect (happy and sad) from realistic images of faces. Our results show that MCMCP requires fewer trials to obtain a higher quality estimate of people’s mental representations of these two categories. (shrink)
In this paper the scientific trajectory of Spanish influential biochemist Alberto Sols (1917-1989) is presented in comparative perspective. His social and academic environment, his research training under the Cori's in the US in the early 1950s and his works when coming back to Spain to develop his own scientific career are described in order to present the central argument of this paper on his path from physiological research to research on enzymatic regulation. Sols' main contributions were both scientific and (...) academic. He and his collaborators not only contributed to biological knowledge on the biochemistry of metabolic regulation but to the active reception of biochemistry in the Spanish academia and to update of Spanish medical education. (shrink)
Carlo Rovelli's relational interpretation of quantum mechanics holds that a system's states or the values of its physical quantities as normally conceived only exist relative to a cut between a system and an observer or measuring instrument. Furthermore, on Rovelli's account, the appearance of determinate observations from pure quantum superpositions happens only relative to the interaction of the system and observer. Jeffrey Barrett () has pointed out that certain relational interpretations suffer from what we might call the ‘determinacy problem', (...) but Barrett misclassifies Rovelli's interpretation by lumping it in with Mermin's view, as Rovelli's view is quite different and has resources to escape the particular criticisms that Barrett makes of Mermin's view. Rovelli's interpretation still leaves us with a paradox having to do with the determinacy of measurement outcomes, which can be accepted only if we are willing to give up on certain elements of the ‘absolute’ view of the world. (shrink)
Using Coffa's paper as a point of departure, this brief note is designed to show that Hempel's inductive-statistical model of explanation implicitly construes explanations of that type as defective deductive-nomological explanations, with the consequence that there is no such thing as genuine inductive-statistical explanation according to Hempel's account. This result suggests a possible implicit commitment to determinism behind Hempel's theory of scientific explanation.
clusions are only probably correct. On the other hand, algorithmic information theory provides a precise mathematical definition of the notion of random or patternless sequence. In this paper we shall describe conditions under which if the sequence of coin tosses in the Solovay– Strassen and Miller–Rabin algorithms is replaced by a sequence of heads and tails that is of maximal algorithmic information content, i.e., has maximal algorithmic randomness, then one obtains an error-free test for primality. These results are only of (...) theoretical interest, since it is a manifestation of the G¨ odel incompleteness phenomenon that it is impossible to “certify” a sequence to be random by means of a proof, even though most sequences have this property. Thus by using certified random sequences one can in principle, but not in practice, convert probabilistic tests for primality into deterministic ones. (shrink)