Exchange the Role of Guest
for that of Host

Defeat the enemy from within by infiltrating the enemy's camp under the guise of cooperation, surrender, or peace treaties. In this way you can discover his weakness and then, when the enemy's guard is relaxed, strike directly at the source of his strength.

Japanese Folk Tale

    In feudal Japan there lived a venerable Kendo master who decided to test his three highest-ranking students. He brought them one by one to an old temple in the nearby mountains where he told each student the following: "You have studied with me many years, now lets see if my teaching has been in vain. There within the temple awaits your test, pass and you will have graduated." 
    Within the dimly lit temple the Master had hidden four Samurai armed with clubs and instructions to jump anyone who entered the temple. The first student entered the temple and before his eyes could adjust to the light, was surprised and beaten by the Samurai.  "I am sorry, you have failed." Said the master.
    The second student entered the temple and sensed the attackers. He was able to deftly evade their attack and defeat them. The student came out of the temple triumphant, but again the master said, "I am sorry, you have failed."
    Finally the third student was brought to the temple and told about the test. The student replied, "But venerable master, protocol dictates that when entering a temple the master must always precede the student, so if you please, I shall follow you in."  To which the master replied, "You rascal, you have learned all I can teach you."