The general who is skilled in defense hides in the most secr... ss. 4.7, Chapter 4: Tactical Dispositions

Hence he does not strive to ally himself with all and sundry... ss. 11.55, Chapter 11: The Nine Situations

When these five kinds of spy are all at work, none can disco... ss. 13.8, Chapter 13: The Use of Spies

If a secret piece of news is divulged by a spy before the ti... ss. 13.19, Chapter 13: The Use of Spies