They betray us, say things we don't want them to know, or say exactly what we would like to say, but can't, or don't have the courage to.
They seduce, deceive, spy, smile, cry, and dream. They also say that the eyes are the mirrors of our souls, and perhaps they are. It could be that all our emotions can come out through them, and cross these colorful orbs to scream something about us to the world. To tell them about us.