We study the spatial adaptive dynamics of a continuous trait that measures individual investment in altruism. Our study is based on an ecological model of a spatially heterogeneous population from which we derive an appropriate measure of fitness. The analysis of this fitness measure uncovers three different selective processes controlling the evolution of altruism: the direct physiological cos...

The individual diagnosed with Narcissistic Personality Disorder presents with grandiosity, extreme self-involvement, and lack of interest in and empathy for others. This paper reviews current theories concerning the development and treatment of Narcissistic Personality Disorder, and introduces the use of Ego State Therapy for its treatment. The ego state model of treatment will be described and...

An intervention study was conducted to investigate whether advanced ego development could be promoted if account was taken of the factors likely to be involved in the ego stage transition process in adulthood. A conceptual framework that identified such factors was described, in which it was hypothesised that stage transition occurs in response to life experiences that are structurally disequil...

An influential line of research suggests that initial bouts of self-control increase the susceptibility to self-control failure (ego depletion effect). Despite seemingly abundant evidence, some researchers have suggested that evidence for ego depletion was the sole result of publication bias and p-hacking, with the true effect being indistinguishable from zero. Here, we examine (a) whether the ...

An influential line of research suggests that initial bouts of self-control increase the susceptibility to self-control failure (ego depletion effect). Despite seemingly abundant evidence, some researchers have suggested that evidence for ego depletion was the sole result of publication bias and p-hacking, with the true effect being indistinguishable from zero. Here, we examine (a) whether the ...

Selfishness is seldom considered a group-beneficial strategy. In the typical evolutionary formulation, altruism benefits the group, selfishness undermines altruism, and the purpose of the model is to identify mechanisms, such as kinship or reciprocity, that enable altruism to evolve. Recent models have explored punishment as an important mechanism favoring the evolution of altruism, but punishm...

Current work on cooperation is focused on the theory of reciprocal altruism. However, reciprocity is just one way of getting a return on an investment in altruism and is di¤cult to apply to many examples. Reciprocity theory addresses how animals respond dynamically to others so as to cooperate without being exploited. I discuss how introducing di¡erences in individual generosity together with p...