Therefore there are five kinds of spies used:
Local spies, internal spies, double spies, dead spies, and living spies. ?
When all five are used, and no one knows their Way, it is called the divine organization, and is the ruler's treasure. ?
For local spies, we use the enemy's people.
For internal spies we use the enemy's officials.
For double spies we use the enemy's spies.
For dead spies we use agents to spread misinformation to the enemy. For living spies, we use agents to return with reports. ?
Therefore, of those close to the army, none is closer than spies, no reward more generously given, and no matter in greater secrecy. ?
Only the wisest ruler can use spies;
only the most benevolent and upright general can use spies, and only the most alert and observant person can get the truth using spies.
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