The devil can cite Scripture for his purpose. -- William Shakespeare

Simply be unwilling to argue. You know that people who argue with anyone, anywhere, at any time are attempting to manipulate and control others by confusing them, wearing them down, and by emotionally and intellectually overpowering them. Alternatively, you consciously present your thoughts, perceptions, intentions, or point of view and stop. You listen and consider what the other person is saying, adjust your ideas and plans as you think is appropriate, but then stop. If the other person wants to pursue the issue, they must do so without your further participation.