Peace war game is an iterated game originally played in academic groups and by

computer simulation Computer simulation is the process of mathematical modelling, performed on a computer, which is designed to predict the behaviour of, or the outcome of, a real-world or physical system. The reliability of some mathematical models can be deter ...

for years to study possible strategies of

cooperation Cooperation (written as co-operation in British English) is the process of groups of organisms working or acting together for common, mutual, or some underlying benefit, as opposed to working in competition for selfish benefit. Many animal ...

and

aggression Aggression is overt or covert, often harmful, social interaction with the intention of inflicting damage or other harm upon another individual; although it can be channeled into creative and practical outlets for some. It may occur either reacti ...

. As peace makers became richer over time it became clear that making war had greater costs than initially anticipated. The only

strategy Strategy (from Greek στρατηγία ''stratēgia'', "art of troop leader; office of general, command, generalship") is a general plan to achieve one or more long-term or overall goals under conditions of uncertainty. In the sense of the " ar ...

that acquired wealth more rapidly was a "

Genghis Khan ''Chinggis Khaan'' ͡ʃʰiŋɡɪs xaːŋbr />Mongol script: ''Chinggis Qa(gh)an/ Chinggis Khagan'' , birth_name = Temüjin , successor = Tolui (as regent)Ögedei Khan , spouse = , issue = , house = Borjigin , ...

", a constant aggressor making war continually to gain resources. This led to the development of the "provokable nice guy"

, a peace-maker until attacked.N.R. Miller
"Nice Strategies Finish First: A Review of ''The Evolution of Cooperation''"
''

Politics and the Life Sciences ''Politics and the Life Sciences'' (PLS) is a peer-reviewed academic journal that was first published in 1982 with Thomas Wiegele as the editor. It is published by Cambridge University Press on behalf of the Association for Politics and the Lif ...

'', Association for Politics and the Life Sciences, 1985. Multiple players continue to gain wealth cooperating with each other while bleeding the constant aggressor. The

Hanseatic League The Hanseatic League (; gml, Hanse, , ; german: label=Modern German, Deutsche Hanse) was a medieval commercial and defensive confederation of merchant guilds and market towns in Central and Northern Europe. Growing from a few North German t ...

for trade and mutual defense appears to have originated from just such concerns about seaborne raiders. The peace war game is a variation of the

iterated prisoner's dilemma The Prisoner's Dilemma is an example of a game analyzed in game theory. It is also a thought experiment that challenges two completely rational agents to a dilemma: cooperate with their partner for mutual reward, or betray their partner ("defe ...

in which the decisions ( Cooperate,

Defect A defect is a physical, functional, or aesthetic attribute of a product or service that exhibits that the product or service failed to meet one of the desired specifications. Defect, defects or defected may also refer to: Examples * Angular defec ...

) are replaced by (

Peace Peace is a concept of societal friendship and harmony in the absence of hostility and violence. In a social sense, peace is commonly used to mean a lack of conflict (such as war) and freedom from fear of violence between individuals or groups. ...

War War is an intense armed conflict between states, governments, societies, or paramilitary groups such as mercenaries, insurgents, and militias. It is generally characterized by extreme violence, destruction, and mortality, using regular o ...

). Strategies remain the same with

reciprocal altruism In evolutionary biology, reciprocal altruism is a behaviour whereby an organism acts in a manner that temporarily reduces its fitness while increasing another organism's fitness, with the expectation that the other organism will act in a similar m ...

, "

Tit for Tat Tit for tat is an English saying meaning "equivalent retaliation". It developed from "tip for tap", first recorded in 1558. It is also a highly effective strategy in game theory. An agent using this strategy will first cooperate, then subsequ ...

", or "provokable nice guy" as the best

deterministic Determinism is a philosophical view, where all events are determined completely by previously existing causes. Deterministic theories throughout the history of philosophy have developed from diverse and sometimes overlapping motives and consi ...

one. This strategy is simply to make peace on the first iteration of the

game A game is a structured form of play, usually undertaken for entertainment or fun, and sometimes used as an educational tool. Many games are also considered to be work (such as professional players of spectator sports or games) or art (suc ...

; after that, the player does what his opponent did on the previous move. A slightly better strategy is "Tit for Tat with forgiveness". When the opponent makes war, on the next move, the player sometimes makes peace anyway, with a small probability. This allows an escape from wasting cycles of retribution, a motivation similar to the Rule of Ko in the game of Go. "Tit for Tat with forgiveness" is best when miscommunication is introduced, when one's move is incorrectly reported to the opponent. A typical

payoff matrix In game theory, normal form is a description of a ''game''. Unlike extensive form, normal-form representations are not graphical ''per se'', but rather represent the game by way of a matrix. While this approach can be of greater use in identifying ...

for two players (A, B) of one iteration of this

is: : Here a player's resources have a value of 2, half of which must be spent to wage war. In this case, there exists a

Nash equilibrium In game theory, the Nash equilibrium, named after the mathematician John Nash, is the most common way to define the solution of a non-cooperative game involving two or more players. In a Nash equilibrium, each player is assumed to know the equ ...

, a mutually best response for a single iteration, here (War, War), by definition heedless of consequences in later iterations. "Provokable nice guy's" optimality depends on iterations. How many are necessary is likely tied to the payoff matrix and

probabilities Probability is the branch of mathematics concerning numerical descriptions of how likely an event is to occur, or how likely it is that a proposition is true. The probability of an event is a number between 0 and 1, where, roughly speakin ...

of choosing. A subgame perfect version of this strategy is "Contrite Tit-for-Tat" which is to make peace unless one is in "good standing" and one's opponent is not. Good ("standing" assumed) means to make peace with good opponents, make peace when bad, or make war when good and opponent is not.

Herbert Gintis Herbert Gintis (February 11, 1940 – January 5, 2023) was an American economist, behavioral scientist, and educator known for his theoretical contributions to sociobiology, especially altruism, cooperation, epistemic game theory, gene-culture co ...

, ''Game Theory Evolving: A Problem-centered Introduction to Modeling Strategic Behavior'',

Princeton University Press Princeton University Press is an independent publisher with close connections to Princeton University. Its mission is to disseminate scholarship within academia and society at large. The press was founded by Whitney Darrow, with the financial su ...

, 2000, p. 133

Notes

{{game theory Dilemmas Moral psychology Non-cooperative games Peace and conflict studies Social psychology Thought experiments

See also

Notes