A lot of people sometimes want to see things from their perpective only. A lot of people sometimes try to put their position in other people's shoes and try to see from that position. Whilst others sometimes assume that they are seen, they did not have a clue at what the people are looking at.
They think they are beautiful, but they forgot that beauty lies on the eyes of the beholder. Whilst those being eyed thought that they are attractive, they did not have a clue at what the people are eyeing at.
In normal circumstances, people do see eye to eye. But because sometimes vision is not perfect, they do don't see eye to eye. And when these differences leads to blood bath and sometimes fatality, then its a case for an eye for an eye.
So, thus its good to have the third eye.
But not to worry, the third eye is only human. When eye meets the eye, the tonque is glued in silence (from the malay words: bila mata bertemu mata, lidah kelu tak terkata kata).