This groundbreaking study examines courtyard architecture across Paris, Florence, Siena, Granada, and Yazd to reveal how the deliberate creation of emptiness—the "bounded void"—functions as architecture's primary generative principle. Moving beyond conventional object-based analysis, the book demonstrates that architecture's essence lies not in built form but in calibrated absence. Through rigorous comparative analysis, readers discover how courtyards operate as environmental mediators, social organizers, and cosmological instruments across diverse cultures. The study reveals striking morphological convergences that emerge through parallel evolution rather than stylistic diffusion. Drawing on spatial cognition research, urban morphology, and phenomenological analysis, the book establishes void-focused methodology as a new theoretical framework. This paradigm shift from analyzing solid to void transforms our understanding of both historical and contemporary spatial practice, uncovering universal principles that transcend geographic and temporal boundaries. Essential for architectural theorists questioning disciplinary orthodoxies, historians seeking alternatives to period-style categorization, and researchers investigating architecture's cognitive dimensions. The work provides both radical historiographical revision and practical insights for contemporary designers engaging with density, sustainability, and social space.