The Boosman-Crocker observation: The Pareto principle is often recursive. (In other words, if 20% of the causes → 80% of the outcomes, then 20%² → 80%², or 4% → 64%. And 20%³ → 80%³, or 0.8% → 51.2%.) I suspect this will be widely accepted one day. h/t @R3TT