In connection with the armies, spies should be treated with the greatest kindness; and in dealing out reward, they should receive the most generous treatment. All matters relating to spies are secret.
Without infinite capacity in the general, the employment of spies is impossible. Their treatment requires benevolence and uprightness. Except they be observed with the closest attention, the truth will not be obtained from them.
Wonderful indeed is the power of spies.
There is no occasion when they cannot be used.
If a secret matter be spoken of before the time is ripe, the spy who told the matter, and the man who repeated the same, should be put to death.
If desirous of attacking an army; of besieging a fortress; or of killing a certain person; first of all, learn the names of the general in charge; of his right-hand[17] men; of those who introduce visitors to the Presence; of the gate keeper and the sentries. Then set the spies to watch them.
Seek out the enemy’s spies who come to spy on us; give them money; cause them to be lodged and cared for; and convert them to the service. Through them we are enabled to obtain spies among the enemy’s villagers and officials.
By means of the converted spy, we can construct a false story for the death spy to carry to the enemy.
It is through the converted spy that we are able to use the five varieties, to their utmost advantage; therefore he must be liberally treated.