Every child knows what it means to play, but the rest of us can merely speculate. Is it a kind of adaptation, teaching us skills, inducting us into certain communities? Is it power, pursued in games of prowess? Fate, deployed in games of chance? Daydreaming, enacted in art? Or is it just frivolity? Brian Sutton-Smith, a leading proponent of play theory, considers each possibility as it has been proposed, elaborated, and debated in disciplines from biology, psychology, and education to metaphysics, mathematics, and sociology.

Sutton-Smith focuses on play theories rooted in seven...