OK

Writing is about conflict.  It can be internal conflict, dealing with opposing ideas inside one's own head.  It can be external conflict, taking place as arguments between people, war between countries (or planets), and anything in between.  In story telling, arguments between people are particularly powerful because they are so human.

Arguments can be difficult, though.  They either end very quickly or not at all.  If somebody is arguing just to make an argument, they can easily be dissuaded by explaining your beliefs and why they are best.  But if somebody is arguing because they believe with all of their heart and soul that you are wrong, there is no amount of words that can convince them otherwise.

In real life, you may want to argue back and forth, over and over again, depending on how stubborn you are.  In writing, though, arguments get old very quickly.  The more sentences you have saying the same things over and over again, the longer you are holding off the action of the story, which will kill your momentum.

In writing, I like to apply the same rule that I apply in real life.  If one person is arguing against an idea and the other person is trying to convince that naysayer, they get three attempts.  Try to make the case and show why it's right, but if the opponent keeps saying no and gives you nothing else to work with, then just say OK.

'OK' is a really great way to end an argument because it infuriates arguers.  You have not conceded your point, but you have refused to continue arguing.  It's kind of like agreeing to disagree, but not both sides have agreed to it. And in writing, it ends those unpleasant arguments before they take over countless pages in your stories.

Actions speak louder than words.  If somebody truly disagrees with you, they won't change their mind until they have personally experienced something that shows that they're wrong.  So rather than mincing words, just say OK and move on to some action.