The Principle of Summation

The principle of Summation, which is a technically sharpened version of the familiar claim that a whole is a sum of its parts, is presented by Peter van Inwagen as a trivial truth. I argue to the contrary, that it is incompatible with the natural assumption that a whole may gain or lose parts non-instantaneously. For, as I show, the latter assumption implies that something can be determinately a whole without being determinately a sum of parts, and this, in turn, indicates the falsity of Summation. I point out that the tension between Summation and the possibility of non-instantaneous gain or loss of parts compels us to rethink the relations between the concepts of whole and sum, and may have far reaching consequences for the mereology of physical objects.

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THE NATURE OF HOPE

Both traditional accounts of hope and some of their recent critics analyze hope exclusively in terms of attitudes that a hoper bears towards a hoped-for prospect, such as desire and probability assignment. I argue that all of these accounts misidentify cases of despair as cases of hope, and so misconstrue the nature of hope. I show that a more satisfactory view is arrived at by noticing that in addition to the aforementioned attitudes, hope involves a characteristic attitude towards an external factor, on whose operation the hoper takes the prospect's realization to depend causally.     

Spatial learning in the 5-HT1B receptor knockout mouse: selective facilitation/impairment depending on the cognitive demand

Age-related memory decline is associated with a combined dysfunction of the cholinergic and serotonergic systems in the hippocampus and frontal cortex, in particular. The 5-HT1B receptor occupies strategic cellular and subcellular locations in these structures, where it plays a role in the modulation of ACh release. In an attempt to characterize the contribution of this receptor to memory functions, 5-HT1B receptor knockout (KO) mice were submitted to various behavioral paradigms carried out in the same experimental context (water maze), which were aimed at exposing mice to various levels of memory demand. 5-HT1BKO mice exhibited a facilitation in the acquisition of a hippocampal-dependent spatial reference memory task in the Morris water maze. This facilitation was selective of task difficulty, showing thus that the genetic inactivation of the 5-HT1B receptor is associated with facilitation when the complexity of the task is increased, and reveals a protective effect on age-related hippocampal-dependent memory decline. Young-adult and aged KO and wild-type (WT) mice were equally able to learn a delayed spatial matching-to-sample working memory task in a radial-arm water maze with short (0 or 5 min) delays. However, 5-HT1BKO mice, only, exhibited a selective memory impairment at intermediate and long (15, 30, and 60 min) delays. Treatment by scopolamine induced the same pattern of performance in wild type as did the mutation for short (5 min, no impairment) and long (60 min, impairment) delays. Taken together, these studies revealed a beneficial effect of the mutation on the acquisition of a spatial reference memory task, but a deleterious effect on a working memory task for long delays. This 5-HT1BKO mouse story highlights the problem of the potential existence of "global memory enhancers."     

Transforming the Problem of the Other: Rethinking Merleau‐Ponty's Itinerary

This essay offers a new understanding of Merleau‐Ponty's notion of the Other, the problem that revolves around it, and its far‐reaching repercussions by shedding light on aspects that usually go unnoticed in the interpretation of his late thought in these regards. I show how Merleau‐Ponty's emerging ontology in his late writings opens anew, in a complex manner, the problem of the Other, transforming it in a way that dismantles, to begin with, traditional epistemological questions regarding the Other, as well as principal difficulties regarding the Other's appearance within the realm of phenomena which have occupied phenomenology from its very beginning. I demonstrate how Merleau‐Ponty's late writings in fact bind the problem of the Other with the question regarding the very limits of phenomenology and the realm of meaning as a whole.     

Relationship Quality among Chronically Ill Children and their Parents

The present study examined the quality of parent–child relationships as reported by 383 parents of chronically ill children. The medical condition category, child’s mobility, education type and childcare assistance were examined. Parents answered the Parent–Child Relationship Inventory (PCRI). In addition, 45 parents of chronically ill children were interviewed. The results indicated a significant difference in most aspects of the PCRI (limit setting, promotion of autonomy, communication, satisfaction and involvement) across medical condition categories. Further child variables (mobility, assistance and education type) had an effect on the PCRI subscales as well. Interview analysis revealed a difference in the reported quality of parent–child relationships between medical conditions categories. Parents of mentally ill children primarily felt anger and guilt in their relationship with their ill children, whereas parents of children with cancer and autoimmune disease primarily felt depressed. Our results suggest the need for further study of parent–child relationships in and between different chronic childhood medical conditions in an attempt to address parents’ and children’s needs in an optimal way.     

BRIEF REPORT

The effects of masking task load on latent inhibition (LI, poorer learning for a previously exposed irrelevant stimulus than for a novel stimulus) were examined as a function of levels of schizotypality. With low load, LI was present in low schizotypal but not high schizotypal participants. With high load, LI was abolished in low schizotypal, but was present in high schizotypal participants. The data support a distraction rather than a resource limitation model of attentional dysfunction in high schizotypal normals. Implications of the model for understanding the attentional dysfunction in schizophrenia are discussed.     

Gender differences in implicit exposure to cyber-pornography

ABSTRACT

Cyber-pornography consumption has become a widespread behavioral habit, with potential diverse outcomes for the user. Previous studies have repeatedly found that males are exposed to cyber-pornography more than females, when they are asked about it explicitly. However, perceived social acceptance of cyber-pornography consumption may dramatically bias such explicit reports. The current study aimed at better understanding gender differences in exposure to cyber-pornography using both explicit self-report measures and a new measure developed to examine exposure to cyber-pornography indirectly. The findings demonstrated gender differences in exposure to cyber-pornography in both measures. Women tended to understate the extent of their exposure. Interestingly, men showed the opposite tendency. Lastly, perceived social acceptance mediated the relationship between gender and explicit report bias. We discuss the conclusions of the current study in relation to previous theories and findings, as well as the importance of using indirect measures to study socially controversial topics such as cyber-pornography.