The tenth chapter classifies six types of terrain and — more importantly — identifies six types of failure that result not from the enemy's strength but from the commander's own errors. The chapter's deepest teaching: know the ground, know the enemy, know yourself, and victory is never in doubt.

The title 地形 (Dìxíng) combines 地 (Dì, earth/ground) with 形 (Xíng, form/shape). It refers to the configuration of terrain — its physical characteristics and strategic implications.

Six Types of Terrain

Sūnzǐ classifies terrain into six categories: accessible ground (通 Tōng, open to both sides), entangling ground (挂 Guà, easy to enter but hard to leave), temporizing ground (支 Zhī, where neither side gains by moving first), narrow passes (隘 Ài), precipitous ground (险 Xiǎn), and positions far from the enemy (远 Yuǎn).

For each, Sūnzǐ provides specific tactical guidance. Accessible ground: occupy high sunny positions with secure supply lines. Entangling ground: do not enter unless the enemy is unprepared. Narrow passes: occupy them first and wait; if the enemy holds them, do not follow unless they are weakly held.

Six Types of Failure

More valuable than the terrain classification is Sūnzǐ's analysis of six causes of military failure — all attributable to the commander rather than to circumstances: flight (attacking a force ten times your size), insubordination (when soldiers are strong but officers are weak), collapse (when officers are strong but soldiers are weak), ruin (when senior officers are angry and insubordinate), disorganization (when the general is weak and undisciplined), and rout (when the general misjudges the enemy's strength).

In self-cultivation, these six failures describe the internal dysfunctions that undermine practice: attempting what is beyond your current level, possessing knowledge without physical conditioning, possessing strength without technical understanding, training with resentment rather than discipline, practicing without consistency or structure, and misjudging your own readiness.

Know the Ground, Know Yourself

The chapter's climactic passage extends the "know the enemy, know yourself" principle from Chapter 3: know the ground and know the weather, and your victory will be complete. The complete general understands three dimensions simultaneously — his own condition, the opponent's condition, and the environment in which they meet. This three-dimensional awareness maps to the martial concept of Sān Cái (三才, the Three Powers): Heaven (timing, conditions), Earth (terrain, spatial relationship), and Human (the practitioner's own readiness).