Abstract

In this book review essay, Justus discusses The Birth of the Mind: How a Tiny Number of Genes Creates the Complexities of Human Thought (2004) by Gary Marcus. The review opens by contrasting the common architectural-blueprint metaphor for the genome with an alternative: the if-then statements of a computer program. The former leads to a seeming “gene shortage” problem while the latter are better suited to representing the cascades of genetic expression that give rise to exponential genotype-phenotype relationships. The essay then develops three conceptual issues of interest to cognitive scientists in light of this small, data-compressed genome: (1) distinguishing dissociations in the developmental process from the domain-specificity of the resulting mental representations, (2) the observation that no gene is specific to a mental representation, a cortical region, or even the nervous system, and (3) the complications that a small number of genes present to the adaptationist programme in evolutionary psychology. The review concludes by questioning the utility of the Swiss Army knife as a metaphor for cognitive development and evolution.