Toward Sustainable Smart Cities With AGI-Enabled Cyber–Physical–Social–Thinking Systems: A Comprehensive Review

Sustainable smart cities require cross-domain, adaptive, and anticipatory intelligence. Current Internet of Things and Artificial Intelligence systems are largely siloed, limiting their ability to support comprehensive urban management. This review addresses this gap by examining the integration of Artificial General Intelligence with the Cyber-Physical-Social-Thinking paradigm. We synthesize research published from January 2015 to September 2025 to provide an overview of how Artificial General Intelligence can serve as the cognitive core, facilitating proactive orchestration across Internet of Things-driven urban layers. Specifically, the paper (1) presents a conceptual analysis of reasoning and meta-cognitive capabilities within the Cyber-Physical-Social-Thinking framework, (2) maps enabling technologies, including digital twins, neuro-symbolic Artificial Intelligence, and the edge-cloud continuum, that operationalize this vision, and (3) reviews applications in mobility, energy management, and climate resilience, highlighting potential gains in efficiency, adaptability, and sustainability. Key technical, ethical, and governance challenges, such as scalability, security, and algorithmic fairness, are discussed. By integrating these insights, the review provides a unified perspective and a roadmap for future research on human-centric, resilient, and sustainable urban intelligent systems.