If I am able to determine the enemy's dispositions while at the same time I conceal my own, then I can concentrate and he must divide.
Sun TzuOf all those in the army close to the commander, none is more intimate than the secret agent.
Sun TzuWhen the position is such that neither side will gain by making the first move, it is called temporising ground.
Sun TzuThe 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 double agents and available for our service. It is through the information brought by the double agent that we are able to acquire and employ local and inward spies. It is owing to his information, again, that we can cause the doomed spy to carry false tidings to the enemy.
Sun Tzu