The Cognitive Kardashev Scale: Quantifying the Material Envelope of Civilisational Computation

ArXi:2605.22840v1 Announce Type: cross How much thinking can a civilisation do? Kardashe's typology ranks civilisations by total power: planetary (Type I, ~10^16 W), stellar (Type II, ~10^26 W), galactic (Type III). This paper builds an analogous Cognitive Kardashe Scale: how much sustained AI-grade computation each tier could. Four ingredients enter the calculation: total power P (watts), the share f of it devoted to cognition, the efficiency $\eta$ at which energy becomes compute (operations per joule), and the brain's own processing rate $C_{\mathrm{brain}}$ as a reference unit.