Page:Sun Tzu on The art of war.djvu/143

Rh there should be any hilly country,
 * 1) 

ponds surrounded by aquatic grass, hollow basins filled with reeds,

or woods with thick undergrowth,

they must be carefully routed out and searched; for these are places where men in ambush or insidious spies are likely to be lurking.

18. When the enemy is close at hand and remains quiet, he is relying on the natural strength of his position.