"Thus, what enables the wise sovereign and the good general to strike and conquer, and achieve things beyond the reach of ordinary men, is FOREKNOWLEDGE. [7]
Now this foreknowledge cannot be elicited from spirits; it cannot be obtained inductively from experience, [8] nor by any deductive calculation. [9]
Knowledge of the enemy's dispositions can only be obtained from other men. [10]
Hence the use of spies, of whom there are five classes: (1) Local spies; (2) inward spies; (3) converted spies; (4) doomed spies; (5) surviving spies.
Knowledge of the enemy's dispositions can only be obtained from other men. [10]
Hence the use of spies, of whom there are five classes: (1) Local spies; (2) inward spies; (3) converted spies; (4) doomed spies; (5) surviving spies."
Sun Tzu–