The Use of Spies

Chapter 13 returns to the accounting of Chapter 2. Raising an army of a hundred thousand and marching them great distances imposes an enormous burden on the people and the state. There will be disruption at home and abroad; as many as seven hundred thousand households may be disrupted from their work. Armies may face each other for years, all for a victory decided in a single day. Given these stakes, to remain ignorant of the enemy's situation because one begrudges the cost of intelligence is a failure of leadership — no real commander, no true asset to the sovereign, no architect of victory. Foreknowledge is what enables great leaders to strike with precision and achieve what ordinary people cannot. And this foreknowledge cannot come from supernatural sources, from inference, from analogy with past events, or from divination. It can only come from people.

Hence the use of spies, of which there are five types. Local spies are recruited from the local population. Inside spies are recruited from the enemy's own officials. Turned spies are enemy agents captured and recruited to work for you. Expendable spies are your own agents deliberately fed false information, allowed to leak it to the enemy — knowing they will likely be exposed and eliminated when the deception is discovered. Surviving spies are those who return with real intelligence from the enemy camp. No one in the entire army should be treated with closer attention than your spies. No one should be more generously rewarded. No operation requires greater secrecy. Spies cannot be effectively managed without keen intuition, integrity, fair dealing, and sharp analytical thinking to determine the truth of their reports.

The chapter closes with the manifesto for the entire book. The ultimate purpose of all five types of espionage is knowledge of the enemy's situation. And that knowledge, in every case, traces back to the turned spy — the converted enemy agent who is the hub through which all other intelligence networks operate. Therefore the turned spy must be treated with the greatest generosity. Only the enlightened ruler and the brilliant commander will use the best minds in the army for intelligence work — and through them achieve what is beyond the reach of ordinary leaders. Spies are the most critical element in warfare, because the army's entire ability to act depends on the intelligence they provide. The book that began with the five factors of planning ends with the one factor that makes the five factors operable: knowledge, and the human beings through whom knowledge is obtained.