Genuine good people follow simple rules:
1. Offer cooperation.
2. If the other accepts cooperation, continue to cooperate.
3. If the other rejects cooperation, respect the rejection.
4. If the other aggresses against you, retaliate.
5. If retaliation was successful, offer cooperation again.
This is a simple algorithm that everyone can understand. Humans know this algorithm by the name "Tit-for-tat":