We test common sense psychology of intragroup relations whereby people assume that intragroup respect and ingroup prototypicality are positively related. In Study 1a, participants rated a group member as more prototypical if they learned that group member was highly respected rather than disrespected. In Study 1b, participants rated a group member as more respected by other group members if they learned that group member was prototypical rather than unprototypical. As a commonsense psychology of groups, we reasoned that the perceived relationship between prototypicality and intragroup respect would be stronger for cohesive groups compared to incohesive groups. The effect of intragroup respect on perceptions of prototypicality (Study 2a & 2c) and the effect of prototypicality on perceptions of intragroup respect (Study 2b) were generally stronger for participants considering cohesive groups relative to incohesive groups. However, the interaction effect of prototypicality and group cohesion on intragroup respect did fail to replicate in Study 2d. In Studies 3, 4a, and 4b we manipulated the relationship between prototypicality and intragroup respect and found that when these variables were in perceptual harmony participants perceived groups as more cohesive. The results of eight out of nine studies conducted are consistent with the prediction that people make inferences about intragroup respect, prototypicality, and group cohesion in a manner that maintains perceptual harmony.

What makes us moral? asks Neil Levy, a philosopher from the University of Melbourne, in a book sporting this title. In particular, Levy examines the roles played by nature and nurture in the origin of moral dispositions. Levy's answer to the question addressed in the book is foreshadowed in the subtitle-"crossing the boundaries of biology"-and stated clearly in the conclusion: "Evolution gave us the preconditions of morality, but it is only as a result of the cultural elaboration of this raw material that we come to be moral beings…We are animals, and we cannot ever free ourselves of our biological heritage. We have no need: it enables all the flexible, rational, and caring behavior that we could want, and allows us to seek to become ever more moral beings" (p. 205). Overall, we recommend this book. Levy is a gifted writer and a clear thinker. He has taken the trouble to study evolutionary theory, and gets it right most of the time. He offers clear analyses of the issues he discusses. He avoids logical fallacies and other conceptual traps found in other writing about evolution and morality, such as viewing humans as either naturally good or naturally bad, assuming that evolutionary theory is genetically deterministic, and attributing to evolutionary theorists the position that the environment does not play an important role in the determination of behavior. He deals with many interesting issues and provides a good history of the development of evolutionary thinking about moral dispositions. He offers a fair overview of criticisms of evolutionary theory, and a reasonable resolution of the controversies in the area. This book is not, however, without problems.

In Kindness in a Cruel World: the Evolution of Altruism, Nigel Barber suggests that "Kindness exists, but it struggles to stay afloat on an ocean of cruelty that is the default condition for organisms competing for existence on this planet" (p. 9). The main premise of Barber's book is that humans inherit a capacity for altruism that can be enhanced or diminished through nurture. Barber suggests that the core of this capacity evolved through kin selection and is reflected in parental investment. From this center, altruism ripples outward in concentric circles to reciprocity between members of ingroups, systems of cooperation in societies, and relations among nations. However, the larger the circle, the weaker the altruistic dispositions. In supporting this model, Barber adduces a potpourri of evidence drawn from a wide array of disciplines, including evolutionary biology, economics, political science, history, social and developmental psychology, game theory, anthropology, and neuroscience. By and large, this book is a good read for lay people and students, but we fear evolutionary psychologists will find many of the analyses simplified and compartmentalized, and some of the conclusions overgeneralized and sensationalized. We were also disappointed by Barber's failure to define the central construct of the book, altruism, in a consistent manner, and his tendency to use the word to refer to quite different phenomena.

We propose a Heiderian common sense psychology (Heider, 1958) of intragroup relations whereby people assume that intragroup respect and ingroup prototypicality are positively related. In Study 1a, participants rated a group member as more prototypical if they learned that group member was highly respected rather than disrespected. In Study 1b, participants rated a group member as more respected by other group members if they learned that group member was prototypical rather than unprototypical. As a commonsense psychology of groups, we reasoned that the perceived relationship between prototypicality and intragroup respect would be stronger for cohesive groups compared to incohesive groups. The effect of intragroup respect on perceptions of prototypicality (Study 2a) and the effect of prototypicality on perceptions of intragroup respect (Study 2b) were stronger for participants considering cohesive groups relative to incohesive groups. In Studies 3 and 4 we manipulated the relationship between prototypicality and intragroup respect and found that when these variables were in perceptual harmony participants perceived groups as more cohesive. Across these six studies, results suggest that people make inferences about respect, prototypicality, and group cohesion in a manner that maintains perceptual harmony. Some possible implications of these inferences are discussed.

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