Smart people are different from people talking smart. Smart people gives comments and if they are wrong, they shut up and go on with life. On the other hand, people talking smarts get angry and talks more and more, they won't stop until someone says they are right.
Have you ever encountered someone who can't drop off an argument? Well, I had. We cannot tell what is in their minds. They keep on repeating words, phrases, and sentences over again without even thinking they are redundant; They can't drop the subject no matter how many times you give your point of view. When everything is supposed to be settled after, they start mentioning about it again. Can't they just shut up and accept the fact that the argument is over?
In our lives people come and go, so if that person won't move on then make the move and leave that person behind. That kind of person is no good for you to spend time with. Once an argument is over then it's over.
If he's wrong then he's wrong, if you're right then you are. People should learn to accept and let go.