Tossing out a brick to get a jade
pāo zhuān yǐn yù
Trick your enemy by making him believe he gains something (or just make him react to it) and obtain something valuable in return.
Lay a trap for your enemy, then lure him into it by using bait. In war the bait is in the form of an illusion of an opportunity for gain. Outside the battlefield the bait is the illusion of wealth, power, and sex.
Offer your enemy something small in order to get in return something big.
Prepare a trap with attractive bait to lure your enemy into an ambush or just in order to move him to a position that is more advantageous to you.
When Chu were besieging Jiao, Chu sent woodcutters to chop down the fine trees outside the city walls.
The enraged commander of Jiao sent out some soldiers to capture the woodcutters, who as a result were handsomely rewarded.
The next day, when more woodcutters arrived, a large amount of Jiao's defenders rushed out hoping of getting their reward. They chased the woodcutters who led them into a trap.
Zhi was preparing to attack Wei and gave their king 400 horses. Wei became suspicious and thus increased their troops at the border. When Zhi saw this they realized their plan had not worked.
The poet Chang Jian, who lived during the Tang dynasty, wanted to the learn from the great poet, Zhao Gu. He wrote half a poem on a temple wall where Zhao was visiting, hoping he would complete it, which actually happened.