Arguing is an act of cooperation. A parent who can't get their child to stop arguing is a parent who is arguing with their child. Come on. Be the parent. Stop entertaining the argument by listening to it. Yes, kids need to know the reason for your rule or decision-the values behind your rules are what you want to move them toward, right? But once an explanation has been given, stop standing there and empowering them to argue with you. Just turn and walk away.