XII. THE ATTACK BY FIRE
1. Sun Tzŭ said: There are five ways of attacking with fire. The first is to burn soldiers in their camp; the second is to burn stores; the third is to burn baggage-trains; the fourth is to burn arsenals and magazines; the fifth is to hurl dropping fire amongst the enemy.
2. In order to carry out an attack, we must have means available. The material for raising fire should always be kept in readiness.
3. There is a proper season for making attacks with fire, and special days for starting a conflagration.
4. The proper season is when the weather is very dry; the special days are those when the moon is in the constellations of the Sieve, the Wall, the Wing or the Cross-bar; for these four are all days of rising wind.
5. In attacking with fire, one should be prepared to meet five possible developments:
6. (1) When fire breaks out inside the enemy’s camp, respond at once with an attack from without.
7. (2) If there is an outbreak of fire, but the enemy’s soldiers remain quiet, bide your time and do not attack.
8. (3) When the force of the flames has reached its height, follow it up with an attack, if that is practicable; if not, stay where you are.
9. (4) If it is possible to make an assault with fire from without, do not wait for it to break out within, but deliver your attack at a favourable moment.
10. (5) When you start a fire, be to windward of it. Do not attack from the leeward.
11. A wind that rises in the daytime lasts long, but a night breeze soon falls.
12. In every army, the five developments connected with fire must be known, the movements of the stars calculated, and a watch kept for the proper days.
13. Hence those who use fire as an aid to the attack show intelligence; those who use water as an aid to the attack gain an accession of strength.
14. By means of water, an enemy may be intercepted, but not robbed of all his belongings.
15. Unhappy is the fate of one who tries to win his battles and succeed in his attacks without cultivating the spirit of enterprise; for the result is waste of time and general stagnation.
16. Hence the saying: The enlightened ruler lays his plans well ahead; the good general cultivates his resources.
17. Move not unless you see an advantage; use not your troops unless there is something to be gained; fight not unless the position is critical.
18. No ruler should put troops into the field merely to gratify his own spleen; no general should fight a battle simply out of pique.
19. If it is to your advantage, make a forward move; if not, stay where you are.
20. Anger may in time change to gladness; vexation may be succeeded by content.
21. But a kingdom that has once been destroyed can never come again into being; nor can the dead ever be brought back to life.
22. Hence the enlightened ruler is heedful, and the good general full of caution. This is the way to keep a country at peace and an army intact.
XIII. THE USE OF SPIES
1. Sun Tzŭ said: Raising a host of a hundred thousand men and marching them great distances entails heavy loss on the people and a drain on the resources of the State. The daily expenditure will amount to a thousand ounces of silver. There will be commotion at home and abroad, and men will drop down exhausted on the highways. As many as seven hundred thousand families will be impeded in their labor.
2. Hostile armies may face each other for years, striving for the victory which is decided in a single day. This being so, to remain in ignorance of the enemy’s condition simply because one grudges the outlay of a hundred ounces of silver in honours and emoluments, is the height of inhumanity.
3. One who acts thus is no leader of men, no present help to his sovereign, no master of victory.
4. 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.
5. Now this foreknowledge cannot be elicited from spirits; it cannot be obtained inductively from experience, nor by any deductive calculation.
6. Knowledge of the enemy’s dispositions can only be obtained from other men.
7. 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.
8. When these five kinds of spy are all at work, none can discover the secret system. This is called “divine manipulation of the threads.” It is the sovereign’s most precious faculty.
9. Having local spies means employing the services of the inhabitants of a district.
10. Having inward spies, making use of officials of the enemy.
11. Having converted spies, getting hold of the enemy’s spies and using them for our own purposes.
12. Having doomed spies, doing certain things openly for purposes of deception, and allowing our own spies to know of them and report them to the enemy.
13. Surviving spies, finally, are those who bring back news from the enemy’s camp.
14. Hence it is that with none in the whole army are more intimate relations to be maintained than with spies. None should be more liberally rewarded. In no other business should greater secrecy be preserved.
15. Spies cannot be usefully employed without a certain intuitive sagacity.
16. They cannot be properly managed without benevolence and straightforwardness.
17. Without subtle ingenuity of mind, one cannot make certain of the truth of their reports.
18. Be subtle! be subtle! and use your spies for every kind of business.
19. If a secret piece of news is divulged by a spy before the time is ripe, he must be put to death together with the man to whom the secret was told.
20. Whether the object be to crush an army, to storm a city, or to assassinate an individual, it is always necessary to begin by finding out the names of the attendants, the aides-de-camp, the door-keepers and sentries of the general in command. Our spies must be commissioned to ascertain these.
21. The enemy’s spies who have come to spy on us must be sought out, tempted with bribes, led away and comfortably housed. Thus they will become converted spies and available for our service.
22. It is through the information brought by the converted spy that we are able to acquire and employ local and inward spies.
23. It is owing to his information, again, that we can cause the doomed spy to carry false tidings to the enemy.
24. Lastly, it is by his information that the surviving spy can be used on appointed occasions.
25. The end and aim of spying in all its five varieties is knowledge of the enemy; and this knowledge can only be derived, in the first instance, from the converted spy. Hence it is essential that the converted spy be treated with the utmost liberality.
26. Of old, the rise of the Yin dynasty was due to I Chih who had served under the Hsia. Likewise, the rise of the Chou dynasty was due to Lü Ya who had served under the Yin.
27. Hence it is only the enlightened ruler and the wise general who will use the highest intelligence of the army for purposes of spying and thereby they achieve great results. Spies are a most important element in war, because on them depends an army’s ability to move.