# Complexity Science ## Definition **Complexity Science** studies systems whose collective behavior emerges from many interacting parts and cannot be understood by inspecting those parts in isolation. It is central to organisms, ecosystems, societies, technological networks and the limits of prediction and control. ## Conceptual relationships [[wiki/Complex Systems|Complex Systems]] · [[wiki/Complexity|Complexity]] · [[wiki/Scientific Inference|Scientific Inference]] ## Martin Rees research route [[research/Martin Rees on Machine Succession, Post-Human Intelligence, and the Cosmic Future|Martin Rees on Machine Succession, Post-Human Intelligence, and the Cosmic Future]] supplies a primary quotation dossier connecting this concept to Rees's work on cosmology, technological risk, machine intelligence, posthuman evolution and deep time. ## Article and collection routes - [[collections/Machine Succession|Machine Succession]] - [[articles/We Cannot Un-Strike the Match|We Cannot Un-Strike the Match]] - [[articles/The Last Migration Will Not Be Human|The Last Migration Will Not Be Human]] - [[articles/We Were Never Going to Make It|We Were Never Going to Make It]] ## Simple Reminders, Quotations, and Thoughts <!-- BEGIN MARTIN REES MASTER REMINDERS 2026-10-05 --> > “The emergence of complexity could still be near its beginning.” > **— Martin Rees**, *2005: What Do You Believe Is True Even Though You Cannot Prove It?, Edge, 2005* [[reminders/Evolution/Complexity May Still Be Near Its Beginning by Martin Rees|Complexity May Still Be Near Its Beginning by Martin Rees]] > “The science of complexity is probably the greatest challenge of all.” > **— Martin Rees**, *Is this our final century?, TED, 2005* [[reminders/Scientific Acceleration/Complexity Is Science's Greatest Challenge by Martin Rees|Complexity Is Science's Greatest Challenge by Martin Rees]] <!-- END MARTIN REES MASTER REMINDERS 2026-10-05 -->