George DuMais

This work explores the possibility of finding scientifically acceptable adaptive explanations of cultural practices. Defining formal adaptive explanations in terms of optimality arguments, I use the semantic conception theories to overcome both a methodological and an ontological objection to adaptive theories in science generally and I establish three criteria that acceptable adaptive explanations must satisfy. I analyze three theories of cultural evolution--the sociobiological theory of Richard Alexander, the Cultural Materialism of Marvin Harris, and a version of the replicator-interactor theory offered by Robert Boyd and Peter Richardson. I argue that all three of these theories fail to meet one or more of the criteria I have established and that the justifications offered for these theories are unsatisfactory. In two detailed case studies of the application of Alexander's theories to an important cultural phenomenon, I scrutinize the well-known work of Martin Daly and Margo Wilson and the oft-cited study of Mildred Dickemann on parental infanticide. In both cases I show that neither the data the authors present nor their interpretation of that data justifies a sociobiological explanation of human parental infanticide. I also analyze Harris's application of cultural materialism to Aztec cannibalism and Yanomamo warfare. I show that in both cases Harris has probably misinterpreted the available evidence. Finally, I argue that all three of these theories are infected by a certain type of reductionism that fails to do justice to the complexity and autonomy of cultural practices, and I sketch out an alternative approach, based on the phenomenon of self-organization, that avoids this error and also overcomes an important philosophical objection to a realist interpretation of adaptive arguments