CHAPTER SUMMARY (9.01-9.46): Contending with Difficult Terrain and Deceptive Enemies
[9.01] Generally, on positioning the army and observing the enemy: To cross mountains, stay close to the valleys; observe on high ground and face the sunny side.* If the enemy holds the high ground, do not ascend and do battle with him. This is positioning the army in the mountains.
[9.02] After crossing a river, you must stay far away from it. If the enemy crosses a river, do not meet him in the water. When half of his forces has crossed,* it will then be advantageous to strike.
[9.03] If you want to do battle with the enemy, do not position your forces near the water facing the enemy; take high ground facing the sunny side, and do not position downstream. This is positioning the army near rivers.
[9.04] After crossing swamps and wetlands, strive to quickly get through them, and do not linger. If you do battle in swamps and wetlands, you must position close to grass, with the trees to your back. This is positioning the army in swamps and wetlands.
[9.05] On level ground, position on places that are easy to maneuver with your right backed by high ground, with the dangerous ground in front, and safe ground to the back. This is positioning the army on level ground.
[9.06] These are the four positions advantageous to the army, which enabled the Yellow Emperor* to conquer four rulers.
[9.07] Generally, the army prefers high ground and dislikes low ground, values the sunny side and despises the shady side, nourishes its health and occupies places with resources, and avoids numerous sicknesses. These factors mean certain victory.
[9.08] Where there are hills and embankments, you must position on the sunny side, with the hills and embankments to your right back.
[9.09] These are advantages to the army.
[9.10] Use the ground for assistance.*
9.01 face the sunny side. Face the sunlit, downward slope. Position your troops in this direction for a clear view of the enemy and to protect themselves.