game-theory-tit-for-tat

Tit for Tat

Cooperate first. Then mirror their last move. Forgive when cooperation returns.

Goal

• Encourage mutual cooperation.
• Avoid exploitation.
• Keep response clear and proportionate.
• Recover quickly after cooperation returns.

Rules

• Be nice: never defect first.
• Be clear: make actions easy to understand.
• Be retaliatory: respond to defection once.
• Be forgiving: return to cooperation immediately after they do.
• Handle noise: clarify ambiguous actions before responding.
• Set exit boundary for repeated defection.

Flow

1. Confirm interaction repeats.
2. Identify their last move.
3. Check if defection was intentional or noise.
4. Choose cooperate, clarify, retaliate once, or exit.
5. Communicate response and recovery path.

Decision guide

• New relationship: cooperate.
• They cooperated: cooperate.
• They defected clearly: defect once, proportionately.
• Intent unclear: ask before retaliating.
• They return to cooperation: forgive.
• Defection repeats: keep boundary or disengage.

Variants

• Generous TFT: forgive occasional defection in noisy environments.
• Tit for Two Tats: retaliate after two defections.
• Gradual TFT: escalate response for repeat offenders.

Resources

• The Evolution of Cooperation - Robert Axelrod
• Veritasium: The Prisoner's Dilemma
• Game Theory 101
• Behavioral Game Theory - Colin Camerer

Output

## Tit for Tat Analysis

Situation: [brief]

## Assessment
- Repeated interaction: [yes/no]
- History: [cooperative/mixed/adversarial]
- Their last move: [cooperate/defect/unclear]
- Noise risk: [low/medium/high]

## Recommendation
- Action: [cooperate/clarify/retaliate once/exit]
- Reason: [TFT rule]

## Message
- [clear communication]

## Exit Condition
- [when to stop engaging]