Sun Tzŭ’s argument is certainly ingenious. He begins by adverting to the frightful misery and vast expenditure of blood and treasure which war always brings in its train. Now, unless you are kept informed of the enemy’s condition, and are ready to strike at the right moment, a war may drag on for years. The only way to get this information is to employ spies, and it is impossible to obtain trustworthy spies unless they are properly paid for their services. But it is surely false economy to grudge a comparatively trifling amount for this purpose, when every day that the war lasts eats up an incalculably greater sum. This grievous burden falls on the shoulders of the poor, and hence Sun Tzŭ concludes that to neglect the use of spies is nothing less than a crime against humanity. 3. 非人之將也非主之佐也非勝之主也 One who acts thus is no leader of men, no present help to his sovereign, An inferior reading for 主 is 仁, thus explained by Mei Yao-ch‘ên: 非以仁佐國者也. no master of victory. This idea, that the true object of war is peace, has its root in the national temperament of the Chinese. Even so far back as 597 B.C., these memorable words were uttered by Prince 莊 Chuang of the Ch‘u State: 夫文止戈爲武 ... 夫武禁暴戢兵保大定功安民和衆豐財者也 “The character for ‘prowess’ (武) is made up of 止 ‘to stay’ and 戈 ‘a spear’ (cessation of hostilities). Military prowess is seen in the repression of cruelty, the calling in of weapons, the preservation of the appointment of Heaven, the firm establishment of merit, the bestowal of happiness on the people, putting harmony between the princes, the diffusion of wealth.” [_Tso Chuan_, 宣公 XII. 3 _ad fin._] 4. 故明君賢將所以動而勝人成功出於衆者先知也 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_. That is, knowledge of the enemy’s dispositions, and what he means to do. 5. 先知者不可取於鬼神不可象於事不可驗於度 Now this foreknowledge cannot be elicited from spirits; 以禱祀 “by prayers or sacrifices,” says Chang Yü. 鬼 are the disembodied spirits of men, and 神 supernatural beings or “gods.” it cannot be obtained inductively from experience, Tu Mu’s note makes the meaning clear: 象, he says, is the same as 類 reasoning by analogy; 不可以他事比類而求 “[knowledge of the enemy] cannot be gained by reasoning from other analogous cases.” nor by any deductive calculation. Li Ch‘üan says: 夫長短闊狹遠近小大卽可驗之於度數人之情僞度不能知也 “Quantities like length, breadth, distance and magnitude, are susceptible of exact mathematical determination; human actions cannot be so calculated.” 6. 必取於人知敵之情者也 Knowledge of the enemy’s dispositions can only be obtained from other men.