Rule of the three thirds

In the rule of the three thirds the object or person that is the strongest is placed on the left hand side, and held on the right side is the weaker. This is performed by most directors, usually when the characters are fighting the stronger is held on the left and weaker on the right.It is also true that the object\person that is contained in the middle is the weakest in the picture. Hierarchies is not only higher and lower it is also front of the frame and back of the frame. Also whats at the top and whats at the front.