The Origin of Mind: Evolution of Brain, Cognition, and General Intelligence

The Origin of Mind presents an evolutionary framework for understanding the development of the human brain, cognition, and general intelligence. David C. Geary integrates research from evolutionary biology, neuroscience, cognitive psychology, developmental psychology, anthropology, and intelligence studies to explain how human mental capacities emerged through natural and sexual selection. The central thesis is that motivational, affective, behavioral, and cognitive systems evolved to enable organisms to gain access to and exercise control over resources associated with survival and reproduction. In humans, these resources are broadly classified as social, biological, and physical. The book begins with an examination of natural and sexual selection before tracing hominid evolution, increases in brain volume, and the emergence of ecological dominance. Geary argues that once human ancestors became increasingly capable of controlling ecological resources, competition within the species intensified, generating selection pressures for more sophisticated social cognition, strategic reasoning, and behavioral flexibility. He subsequently analyzes the interaction between inherited constraints and developmental experience in shaping brain organization and cognitive functioning. A major component of the book is the distinction between evolutionarily primary cognitive systems and more flexible, controlled forms of problem-solving. Primary systems include intuitive competencies in folk psychology, folk biology, and folk physics. These domain-specific capacities are contrasted with conscious reasoning, mental simulation, executive control, and general intelligence, which allow individuals to manage novel and unpredictable situations. The final chapters examine the evolution, measurement, genetic and environmental foundations, and contemporary social significance of general intelligence. Overall, the work offers an ambitious interdisciplinary account of the human mind as an adaptive system shaped by ecological challenges, social competition, developmental plasticity, and the continuing interaction between biological inheritance and cultural experience.