Logic is the ultimate law.
Do not do to others what they would not want to be done to them, or you will be punished regardless of your will.
The purpose of punishment is to erase guilt, via retribution and restitution.
That is the entire law; it cannot be changed, all the rest is commentary.
From this law, a complete framework for justice, economics, and science follows without contradiction. This site is an interactive curriculum for understanding that framework.