Modularity has been the subject of intense debate in the cognitive sciences for more than 2 decades. In some cases, misunderstandings have impeded conceptual progress. Here the authors identify arguments about modularity that either have been abandoned or were never held by proponents of modular views of the mind. The authors review arguments that purport to undermine modularity, with particular attention on cognitive architecture, development, genetics, and evolution. The authors propose that modularity, cleanly defined, provides a useful framework for directing research and resolving debates about individual cognitive systems and the nature of human evolved cognition. Modularity is a fundamental property of living things at every level of organization; it might prove indispensable for understanding the structure of the mind as well.

Humans are an exceptionally cooperative species, but there is substantial variation in the extent of cooperation across societies. Understanding the sources of this variability may provide insights about the forces that sustain cooperation. We examined the ontogeny of prosocial behavior by studying 326 children 3-14 y of age and 120 adults from six societies (age distributions varied across societies). These six societies span a wide range of extant human variation in culture, geography, and subsistence strategies, including foragers, herders, horticulturalists, and urban dwellers across the Americas, Oceania, and Africa. When delivering benefits to others was personally costly, rates of prosocial behavior dropped across all six societies as children approached middle childhood and then rates of prosociality diverged as children tracked toward the behavior of adults in their own societies. When prosocial acts did not require personal sacrifice, prosocial responses increased steadily as children matured with little variation in behavior across societies. Our results are consistent with theories emphasizing the importance of acquired cultural norms in shaping costly forms of cooperation and creating cross-cultural diversity.development | population differences | gene-culture coevolution

Intent and mitigating circumstances play a central role in moral and legal assessments in large-scale industrialized societies. Although these features of moral assessment are widely assumed to be universal, to date, they have only been studied in a narrow range of societies. We show that there is substantial cross-cultural variation among eight traditional small-scale societies (ranging from hunter-gatherer to pastoralist to horticulturalist) and two Western societies (one urban, one rural) in the extent to which intent and mitigating circumstances influence moral judgments. Although participants in all societies took such factors into account to some degree, they did so to very different extents, varying in both the types of considerations taken into account and the types of violations to which such considerations were applied. The particular patterns of assessment characteristic of large-scale industrialized societies may thus reflect relatively recently culturally evolved norms rather than inherent features of human moral judgment. morality | intentions | cognition | culture | human universals

Recent work has proposed that social norms play a key role in motivating human cooperation, and in explaining the unique scale and cultural diversity of our prosociality. However, there has been little work directly linking social norms to the form, development, and variation in prosocial behavior across societies. In a cross-cultural study of eight diverse societies, we provide evidence that (1) adults' prosocial behavior is predicted by what other members of their society judge to be the correct social norm, (2) children's responsiveness to novel social norms develops similarly across societies, and (3) societally-variable prosocial behavior develops concurrently with children's responsiveness to norms in middle childhood. These data support the view that the development of prosocial behavior is shaped by a psychology for responding to normative information, which itself develops universally across societies.

Blank-slate theories of human intelligence propose that reasoning is carried out by general-purpose operations applied uniformly across contents. An evolutionary approach implies a radically different model of human intelligence. The task demands of different adaptive problems select for functionally specialized problem-solving strategies, unleashing massive increases in problem-solving power for ancestrally recurrent adaptive problems. Because exchange can evolve only if cooperators can detect cheaters, we hypothesized that the human mind would be equipped with a neurocognitive system specialized for reasoning about social exchange. Whereas humans perform poorly when asked to detect violations of most conditional rules, we predicted and found a dramatic spike in performance when the rule specifies an exchange and violations correspond to cheating. According to critics, people's uncanny accuracy at detecting violations of social exchange rules does not reflect a cheater detection mechanism, but extends instead to all rules regulating when actions are permitted (deontic conditionals). Here we report experimental tests that falsify these theories by demonstrating that deontic rules as a class do not elicit the search for violations. We show that the cheater detection system functions with pinpoint accuracy, searching for violations of social exchange rules only when these are likely to reveal the presence of someone who intends to cheat. It does not search for violations of social exchange rules when these are accidental, when they do not benefit the violator, or when the situation would make cheating difficult.evolutionary psychology | reasoning | cooperation | reciprocation T o the human mind, certain things seem intuitively correct. The world seems flat and motionless; objects seem solid rather than composed of empty space, fields, and wave functions; space seems Euclidian and 3-dimensional rather than curved and 11-dimensional. Because scientists are equipped with human minds, they often take intuitive propositions for granted and import them-unexaminedinto their scientific theories. Because they seem so self-evidently true, it can take centuries before these intuitive assumptions are questioned and, under the cumulative weight of evidence, discarded in favor of counterintuitive alternatives-a spinning earth orbiting the sun, quantum mechanics, relativity.For psychology and the cognitive sciences, the intuitive view of human intelligence and rationality-the blank-slate theory of the mind-may be just such a case of an intuition-fueled failure to grapple with evidence (1-4). According to intuition, intelligence-almost by definition-seems to be the ability to reason successfully about almost any topic. If we can reason about any content, from cabbages to kings, it seems self-evident that intelligence must operate by applying inference procedures that operate uniformly regardless of the content domains they are applied to (such procedures are general-purpose, domain-general, and content-independent). Consulting su...