You write things down and agree upon them beforehand precisely to prevent things from changing. When two teams go out to play football, they can rest assured that the referees are going to call the game based upon a set of rules that the clubs assented to. They don't decide on a whim to make a touchdown 10 points because one side is losing too badly. The rules are the rules and they are agreed upon beforehand. This can not be stressed enough.
It is the same with a business that contracts for services. They decide beforehand and write down the terms. Then both agree to the terms, if they desire.
A society is to be run no differently. A would-be thief knows that what he is doing is against the rules and that there is a punishment for it. The entire idea of rule of law is that people can make choices based up a predetermined set of rules, that all agree to abide by. When judges and juries make up laws on the spot and punish people and companies for not obeying this new "law" that they had had no knowledge of existing is to introduce chaos and uncertainty where order should be.
SD
Exactly!
And I interject that the "predetermined set of rules" can never change - for the simple fact you point out that they have to be "agreed up by ALL".
*Not Applicable in New Jersey