"Naturally, all generals of the fourth century BC did not attain the position by reason of their abilities. But by this time is was possible for an able man to rise to command rank without respect to aristocratic origin and to receive at a ceremonial investiture THE BATTLE-AXE which symbolized his status as commander-in-chief and conferred upon him supreme authority outside the capital."

S.B Griffith, Sun Tzu The Art of War pp 58.