Natural selection, mental modules and intelligence.

Abstract

The question of whether intelligence is one trait or many has exercised several generations of researchers, but no consensus is in sight. Evolutionary psychology, with its emphasis on domain-specific mental modules, seems to offer hope for advancing understanding of this question. We know that the mind has been shaped by natural selection to maximize reproductive success. This tells us what the mind must do--it must solve the adaptive problems that the organism confronts. However, whether this functional capacity is manifest in congruent anatomic, physiological, genetic, cognitive or psychometric structures is another matter. Examination of how natural selection shaped other mechanisms suggests that knowing functional demands provides only modest guidance as to the structure of mechanisms. None the less, it remains simultaneously clear that these mechanisms are not entirely general, but have been shaped to cope with specific challenges. Our metaphors for the mind, whether as a digital computer or a Swiss army knife, are misleading because computers and tools are products of intelligent design. In contrast, minds are products of natural selection whose intertwined components are products of incorporated genetic mutations whose effects are widespread and constrained by historical precedents. Our tendencies to describe the structure of the mind in terms of discrete components make it difficult for us to comprehend the mind as a mind. One antidote may be to minimize metaphorical descriptions of postulated structures of mind and focus instead on its function.