Thinking Complexity — 20 years at IXXI

4–6 November 2026

Attention : changement de lieu

La Verriere, 6bis boulevard de l'Artillerie, 69007 Lyon

Metro B station Jean Jaurès

Wednesday, Nov. 4th — Morning

What are complex systems? (Philosophy & Epistemology)

TimeSpeakerAffiliationTitle
09:00–09:30Patrice Abry, Emmanuel Trizac - IXXI, ENS Lyon - Opening ceremony
09:30–10:15 Karoline Wiesner University of Potsdam From Emergence to Explanation: The Science of Complex Systems
10:15–10:45Coffee break
10:45–11:30 Jean-Pierre Dupuy Stanford University The Self-Transcendence of the Future
11:30–12:15Sara Franceschelli - Fausto Fraisopi - Questions & discussions
12:30–14:30Lunch

Wednesday, Nov. 4th — Afternoon

Complex systems & physics, graphs and networks, biology

TimeSpeakerAffiliationTitle
14:30–15:15 Marc Mézard Bocconi University, Milano, Italy Memorization and generalization in the light of generative AI
15:15–16:00 Albert-László Barabási Network Science Institute and Department of Physics, Northeastern University, Division of Network Medicine, Harvard University, Department of Network and Data Science, Central European University Network Science: Decoding the Architecture of Complexity
16:00–16:30Coffee break
16:30–17:15 Sergi Valverde IBE, CSIC–UPF, Barcelona Software as an Evolving Ecology: Tinkering, Spandrels, and the Growth of Artificial Complexity
17:15–18:00Pierre Borgnat - Annick Lesne - Questions & discussions

Wednesday, Nov. 4th — Evening

Complex systems & institutions

TimeSpeakerAffiliationTitle
18:20–18:40 Michel Morvan Co-Founder and Chief Science Officer of Cosmo Tech, President of IRT SystemX From Academia to Industry: Translating Complex Systems Research into Practice
18:40–19:00 Annick Lesne CNRS & University of Montpellier Promoting the science of complex systems in France, from 2000 to present
19:00–19:20 Guillaume Beslon - Questions & discussions
19:30–19:50 Jean Dhombres Ecole des Hautes Etudes en Sciences Sociales Epistemological perspectives on twenty years of IXXI: a tentative of cross-analysis of reports, readings and interviews
19:50–20:10 Jean-Philippe Magué ENS Lyon IXXI as a dynamical system: 20 years of archives
20:10–20:30 Patrice Abry - Questions & discussions
20:30–22:00Cocktail reception

Thursday, Nov. 5th — Morning

Complex systems & neurosciences, economics, ecosystems

TimeSpeakerAffiliationTitle
10:00–10:45 Fabrizio De Vico Fallani NERV Lab, Paris Brain Institute Networked minds: from brains to machines
10:45–11:30 Tiziana Di Matteo King's College, London Thinking Complexity in Economic and Financial Systems: An Econophysics Perspective
11:30–12:00Coffee break
12:00–12:45 Sonia Kéfi CNRS & ISEM Montpellier Nature: resilient yet fragile
12:45–13:30Cécile Bastidon - Marton Karsai - Questions & discussions
13:30–15:30Lunch

Thursday, Nov. 5th — Afternoon

Complex systems & social sciences

TimeSpeakerAffiliationTitle
15:30–16:15 Céline Rozenblat Institut de géographie et de durabilité - Université de Lausanne Multi-scale resilience of urban complex systems
16:15–17:00 Márton Karsai Central European University / HUN-REN Rényi Institute of Mathematics Socioeconomic networks, segregation patterns, and their dynamics
17:00–17:45 Eric Guichard, David Chavalarias - Questions & discussions
17:45–18:30Coffee break

Thursday, Nov. 5th — Evening

Complex Systems & Arts, Science, Society

TimeSpeakerAffiliationTitle
18:30-19:15 Fausto Fraisopi Aix-Marseille University Escaping linearity and plate ontologies. Complexity between Art and Science
19:15–20:00 Sara Franceschelli, Patrice Abry IXXI, ENS Lyon Art & Science Experience. A journey at the frontiers of interdisciplinarity
20:00–20:15 Annick Lesne - Questions & discussions
20:15-21:00 Art-Science performances
21:00–22:00Cocktail reception

Friday, Nov. 6th — Morning

Complex systems & challenges for the future

TimeSpeakerAffiliationTitle
09:00–09:45 Brian Castellani Durham Research Methods Centre, Durham University What Are Complex Systems? Ontology, Epistemology and the Social Science Turn
09:45–10:30 David Chavalarias Centre d'Analyse et de Mathématique Sociales & Complex Systems Institute of Paris IdF The artificialization of cultural evolution: the impact of very large digital infrastructures on individuals and society
10:30–11:00 Pablo Jensen, Céline Rozenblat- Questions & discussions
11:00–11:30Coffee break
11:30–13:00 Round table: The future of complex systems and their potential contributions to major societal stakes and to crisis solutions Cécile Bastidon, Sara Franceschelli
13:00–13:15Concluding remarks