In ancient times the rise to power of the province of Yin was due to Ichih, who was sent to the country of Hsia. Likewise during the foundation of the state of Chu, Luya lived among the people of Shang.
Wherefore, intelligent rulers and wise generals use the cleverest men as spies, and invariably acquire great merit. The spy is a necessity to the army. Upon him the movement of the army depends.
[THE SAYINGS OF WUTZU]
[INTRODUCTION]
Now Wu, albeit clothed in the raiment of a scholar, was a man skilled in the art of war.
And Wen, Lord of Wei, came unto him and said:—
“I am a man of peace, caring not for military affairs.”
And Wu said:—