How active inference and the free energy principle transform our understanding of technology and design.Design for Entropy offers a bold rethinking of human-technology relations by bringing active inference and the Free Energy Principle—leading frameworks in neuroscience and cognitive science—into dialogue with design theory, as well as the sociology and psychology of technology.Luca Possati argues that any artifact—any technology—can be understood as a network of predictions and predictive models about human behavior and its environment. The active inference agent is, by definition, a technological agent—one whose survival and adaptation depend on the ability to construct, reshape, and inhabit a predictive niche. This perspective opens the door to a new approach for addressing foundational questions about design and the role of technology in social groups and the psychological dynamics of human-technology interaction.Through in-depth case studies—covering smartphones, adaptive robotics, and smart cities—Possati introduces the Designer-Artifact-User (DAU) software model, an active inference-based tool for UX design. He also confronts psychological and social challenges, including digital addiction, depression, affective modulation, and the role of technology in mentalizing.