Shared concepts between complex systems and the game of Go Bruno Bouzy Tristan Cazenave LAFORIA-IBP Université Pierre et Marie Curie 4, place Jussieu 75252 PARIS CEDEX 05 FRANCE Tel: 44 27 70 10 Fax: 44 27 70 00 bouzy@laforia.ibp.fr cazenave@laforia.ibp.fr Abstract We developed complex systems playing the game of Go using specific concepts and methods. Due to the inherent complexity and to the riches of the game of Go, some concepts can be shared with other complex domains. We present links with domains such as Economy, Social Sciences, War simulation, Linguistic, Biology and Earth Sciences. Links with Economy are based on investment and decision making. Links with Social Sciences deal with the relative importance of social agents. War simulation uses strategic concepts of Go. Go provides Linguistic with two-dimensional representations. Biology and Computer Go deal with ontological problems. Earth Sciences and Computer Go give place to chaotic and complex behaviours. Résumé Nous avons développé des systèmes complexes jouant au Go en utilisant des concepts et des méthodes spécifiques. La complexité inhérente du jeu de Go et ses richesses permettent de généraliser ces concepts à d'autres domaines. Nous présentons des liens avec l'économie, les sciences sociales, la linguistique, la biologie et les sciences de la Terre. Les liens avec l'économie sont basés sur l'investissement et la prise de décision. Les liens avec les sciences sociales traitent de l'importance relative des agents sociaux. La simulation de la bataille utilise des concepts stratégiques présents au Go. Celui-ci fournit des représentations originales utilisables en lingistique. La biologie et le Go traitent de problèmes ontologiques. Les sciences de la Terre et le Go donnent lieu à des comportements complexes et chaotiques. 1 Introduction We both have achieved complex systems playing an entire game of Go 1 (Gogol [Cazenave 1994] and Indigo [Bouzy 1995]) using specific concepts and methods. The purpose of this paper is to show various links between our work and other complex domains. In section 2, we begin making analogies between Go and domains studying human interactions (Economy, Social Sciences, War). In section 3, we continue showing interdependencies between Go and Linguistic. In sections 4 and 5, we follow by analogies with Biology and Earth sciences. Then, we conclude in section 6. 1 The game of Go is a very complex two-person, complete information game. Its complexity is high, there is an average of 180 possible moves, a game lasts about 300 moves. A position is hard to evaluate, and a good evaluation function needs a lot of knowledge. In comparison to Chess complexity (10 43 ), Go complexity(10 172 ) is approximatively higher by a factor 10 130