Overview

Life is a game. Your success depends not just on what you do, but on what others do. Game theory analyzes these strategic interactions, from poker to nuclear war.

Core Idea

Nash Equilibrium: A situation where no player can benefit by changing their strategy while the other players keep theirs unchanged. It’s a state of “no regrets.”

Formal Definition (if applicable)

Prisoner’s Dilemma: A standard example where two rational individuals might not cooperate, even if it appears that it is in their best interest to do so.

  • If both cooperate: 1 year jail each.
  • If one betrays: 0 years for betrayer, 3 years for cooperator.
  • If both betray: 2 years jail each. Nash Equilibrium: Both betray (and get a worse outcome than if they cooperated).

Intuition

Imagine two drivers at an intersection.

  • If both go: Crash (Bad).
  • If both stop: Wait (Okay).
  • If one goes and one stops: Smooth traffic (Good). Game theory helps predict what will happen.

Examples

  • Cold War: Mutually Assured Destruction (MAD) was a Nash Equilibrium.
  • Auctions: Designing rules to get people to bid their true value.
  • Evolutionary Biology: Hawk-Dove game explaining animal aggression.

Common Misconceptions

  • “It’s about winning games.” (It’s about understanding strategy in any interaction.)
  • “Rational means selfish.” (You can have altruistic preferences in game theory.)
  • Zero-Sum Game: One person’s gain is another’s loss (Poker).
  • Non-Zero-Sum Game: Win-win or lose-lose is possible (Trade).
  • Coordination Game: Players benefit from choosing the same option (Driving on the right side of the road).

Applications

  • Economics: Oligopoly pricing.
  • Political Science: Voting systems and international treaties.
  • Computer Science: Network routing and AI.

Criticism / Limitations

Assumes players are perfectly rational and have infinite computing power, which real humans do not.

Further Reading

  • Von Neumann & Morgenstern, Theory of Games and Economic Behavior
  • Schelling, The Strategy of Conflict