Attacking the unprepared, doing the unanticipated

The above phrase was quoted from Kongming who cleverly detected Zhou Yu's ruse to kill Xuande when the former's army was in JingZhou to collect grain and cash. The proposed plan was to conquer the Riverlands in order for Xuande to turn over JingZhou, but the real intention was to abduct and eliminate Xuande when he received the troops as they crossed his territory to 'invade' the Riverlands. This strategy is akin to "passing through on the pretext of conquering Guo".

In present life, the quote above refers to the ability to disinguish between right and wrong, to surprise your enemies and awe your allies. We cannot keep acting conventionally. We cannot act as others percieve us to be.

There are more meanings, but they cannot be put into words.