Sure, there have to be some rules, any things that are hard coded into the framework would be an example, but as a general principle, I think principles are more useful than rules. When it comes to giving guidance on how people should conduct themselves or what type of content is appropriate, I think it would be more effective to communicate in terms of principles rather than giving people a list of hard rules. As @bullionstackers said, these are all negative. I think people may respond better to a positive message.