Maxim: Νομω πειθου or "Obey the Law"
Modern Interpretation: Obey the Law
This one is another one which is pretty dang straight-forward. Obey the law. A simple phrase, a simple concept, but why is it important? Obeying laws results in community cohesion. When no one is stealing from another person, we can trust each other more. When no one is hurting other people, we fear each other less, and trust each other more, and when it comes to human friendships trust is vital. Obeying the law is absolutely vital to being able to trust one another. This also extends to groups that you are a member of. You should obey the laws of the group. If your club has a code of conduct, follow it, if your workplace has dress standards, follow them. Following the rules is overall a good decision, and will save you a lot of strife.
Though, there are times when this falls apart.
Sometimes rules are made to be broken. When the law of your land imposes upon the basic liberties of being able to be who you are, and being able to speak your mind, perhaps it is time to disregard this maxim. In America, we aren't going to have as much opportunity for this, but there are many countries in the world where women can't get an education or speak their mind. There are many countries where being gay will result in a stoning. There are many countries where disagreeing with the government will result in execution. Sometimes the law can be wrong.
Use the gift of reason
Obey the law, but use your head.