Agent-Based Evolving Societies From Tribes to Chiefdoms to Nations Loïs Vanhée, Jacques Ferber, Frank Dignum Université Montpellier 2 Utrecht Universiteit ESSA 2013

Agenda From Social Science Descriptions… …To a method to build models of evolving societies… … To a concrete implementation Disclaimer: our goal is the method* *Our implementation is an illustration, real-societies may not proceed like this *A more detailed model/simulation may come in a year

Dear social sciences, Societies appear to evolve through ages. Do you know more about that? (note: this picture may not be representative of the average social scientist. Google result for “wise man”) Sure, I have clustered them!

From SS: Clustering societies Tribe Chiefdom Nation Kinship PowerRules Social Individual

Dear social sciences, Plus, they evolve from one stage to the next How do they? Well, I cannot really say. It depends on so many things… But I can tell how it did for pigmies, Romans, Gallices Okay… I have to simplify and generalize these transitions by myself… *If you have super theories about social stage evolution, please manifest yourself during the questions

From SS: evolving societies Tribe Chiefdom Nation Kinship PowerRules

From SS: evolving societies Tribe Chiefdom Nation Kinship PowerRules Power Education Population Growth Loss of kin-based relationship Creation of a militia owned by a leader Violent uncontrolled conflicts Militia hires militiamen Militiamen prevent fights Problem controlled Population Growth Leader cannot control everyone Individuals disagree with the leader Creation of an “education” institution “Professors” are hired Individuals are taught rules (law, obedience) Problem controlled Individuals are collectively aware of it

Dear social sciences, No problem, it can be expanded for concrete examples. Wait a minute! I can see a more global pattern. Let me build a method to prevent other modelers to suffer my pain. Damn modeler, you simplified everything. But now, your model cannot be linked to any real society.

A method to build evolving societies Normal state Local problem Social problem Resolving institution Resolving behavior Problem occurrence Communication Social action Hiring agents Handling the problem Such a text corresponds to implementation-level information Local memory l Communication, opinion-merging mechanism m Collective decision mechanism d Behavior : b Institution i

Sketch of Concrete Implementation Tribe Chiefdom Kinship Power Population Growth Loss of kin-based relationship Creation of a militia owned by a leader Violent uncontrolled conflicts Militia hires militiamen Militiamen prevent fights Problem controlled Individuals are collectively aware of it Gather & share food Reproduce [Sugarscape-like] External: easier to harvest food Graph or family size When population grows → sparse relationships Individuals randomly meet Fight with out-groups l = memorize when attacked (social dissatisfaction) m = voting mechanism (yes if l is high) d= 50% yes Majority: an agent becomes the leader o A variable stores the ratio of militiamen These agents stop harvesting Militia influences random meetings (no fight when watched) b

Experimentations Growth period: food production increases each round

From SS: evolving societies Chiefdom Nation PowerRules Population Growth Leader cannot control everyone Individuals disagree with the leader Creation of an “education” institution “Professors” are hired Individuals are taught rules (law, obedience) Problem controlled Individuals are collectively aware of it From before: Random meetings External: easier to harvest food Variable for “culture” (vector) Evolve randomly with time → cultural variation increases with society size Mismatch leader/subordinate cultures l = individual disagreement m = average mismatch d: m is too high A variable stores the ratio of professors i: professor institution Professors increase cultural match b

Experimentations

Conclusions From SS theories of human development – Tribes, chiefdom, nations To a method to model of extensible societies – Stability; local problem; social problem; resolving institution; resolving behavior; stability Applied in a simulation – Creation of a militia, teaching institution – Two consecutive levels Future work: – Use the method for artificial societies (swarm of robots) – Expand the model: a different social reality for each stage

Thank you for you attention Any questions?