A minimally invasive surgical instrument is provided, comprising a shaft and an end effector connected to the shaft, wherein the end effector operates in the pitch or yaw direction against the shaft when a first wire and a second wire conveyed through the shaft operate cooperatively according to a first aspect and the end effector operates in the roll direction against the shaft when the first wire and the second wire operate cooperatively according to a second aspect, wherein the first wire and the second wire operate in the same direction when the cooperative operation is according to one aspect of the first aspect and the second aspect and the first wire and the second wire operate in the opposite directions when the cooperative operation is according to the other aspect of the first aspect and the second aspect.
