Principles are ways of successfully dealing with reality to get what you want out of life.
Ray Dalio, one of the world’s most successful investors and entrepreneurs, cites principles as his key to success.
The main purpose of discussion is to achieve completion and get in sync, which leads to decisions and/or actions. Conversations that fail to reach completion are a waste of time. When there is an exchange of ideas, it is important to end it by stating the conclusions. If there is agreement, say it; if not, say that. Where further action has been decided, get those tasks on a to-do list, assign people to do them, and specify due dates. Write down your conclusions, working theories, and to-do's in places that will lead to their being used as foundations for continued progress. To make sure this happens, assign someone to make sure notes are taken and follow-through occurs.
There is no reason to get angry because you still disagree. People can have a wonderful relationship and disagree about some things; you don't have to agree on everything.