Book: Physical Basis Of Mind

Overview
George Henry Lewes sets out a sustained inquiry into how mental life is grounded in bodily processes, arguing for a naturalistic account of consciousness that ties psychology to physiology. He treats mind and brain as correlated aspects of complex organic activity, rejecting metaphysical dualism while resisting crude mechanistic reduction. The work blends experimental physiology, comparative biology, and philosophical analysis to map the contours of a physicalist psychology.

Mind and Brain: a Correlative View
Lewes insists that mental states are not mysterious substances separate from the body but are functions correlated with specific nervous and organic states. He develops a correlative framework in which every class of mental phenomena, sensations, perceptions, emotions, associations, volitions, has an underlying physiological counterpart. Correlation is not presented as mere parallelism without content; rather, it is a systematic proposal that mental qualities arise from, and can be explained by, the organization and interplay of bodily processes.

Physiology and Psychological Mechanisms
The book surveys known mechanisms of nerve and brain function as the explanatory soil from which mental phenomena grow. Lewes draws on experiments about nerve conduction, excitation and inhibition, and the plasticity of nervous tissue to explain memory, habit, and attention. He treats association by contiguity and repetition as rooted in changed excitability and structural modification of neural circuits, and he frames volition as a resultant of competing physiological processes shaped by habit and temperament.

On Consciousness and Emergence
Lewes confronts the problem of consciousness with a theory that balances reduction and emergence. Subjective qualities are not dismissed as illusory, but are seen as higher-level properties that emerge from complex, organized life: the whole exhibits features not predicted by an account of isolated parts. Consciousness, on this view, is an outcome of integrative physiological activity, a standing and dynamic expression of the organism's systemic states rather than an additional ontological ingredient.

Method and Comparative Approach
Empirical breadth marks Lewes's method: comparative anatomy, observations from development and pathology, and reference to animal behaviour contribute to his psychological generalizations. He emphasizes the value of experimental physiology and careful observation over speculative metaphysics, while acknowledging the limits of contemporary instruments and knowledge. Lewes frequently appeals to evolutionary continuity to justify the extension of physiological explanations across species and to illuminate the progressive complexity of mental life.

Critique of Dualism and of Simple Materialism
Lewes criticizes Cartesian dualism as incoherent with biological facts, arguing that a severed mind cannot be intelligibly located apart from the living, functioning body. At the same time, he rejects a simplistic materialism that would reduce feeling and purpose to mere mechanical motion without accounting for organizational complexity. His stance aims at a middle path that recognizes biological organisation as the crucial mediator between matter and mind.

Legacy and Limits
The argument anticipates later developments in physiological psychology and the philosophy of mind by insisting on empirical grounding and by framing mental phenomena as biologically based functions. Some explanatory moves reflect the scientific limitations of the era, leaving mechanistic gaps that later neuroscience would fill or revise. Nevertheless, the emphasis on correlation, emergence, and the primacy of organic organization remains influential as an early systematic attempt to place mental life squarely within the natural order.