Downward Causation

Book excerpt: Downward causation is found in two-level and multi-level systems with complex behaviour generated by many components interacting in a simple or complex way. The term was coined by the social psychologist and philosopher Donald T. Campbell, who asked the question: If many small-scale interactions can create emergent large-scale patterns, can large-scale patterns re-influence the small-scale interactions that generated them? This has led to many further questions, among them: Does the cell as a system reorganise the biochemical processes inside it in a new way? Do psychosomatic illnesses exist? Can life change biochemical laws? Can mind change the body? The chapters in this comprehensive book address these questions from the viewpoints of different disciplines. Part 1 contains a classification of positions regarding 'downward causation', Part 2 covers physics, Part 3 covers biology and psychology, Part 4 covers social and communicative systems, and Part 5 covers general philosophy.