Shi (potential force) is Robert Greene's read of a core Sun Tzu concept, recovered from a dense ~700-page annotated edition of The Art of War that glosses the literal, physical meaning of each character — something the common thin English translations flatten into abstract language.
The essence of strategy is not choosing a specific move — it's maneuvering into a position of latent, multidirectional power from which many powerful outcomes become possible. What you actually do next matters less than the position you occupy before you do it.
Both images carry the same point: force that has been gathered but not yet spent is more strategically supple than force already committed to one direction.
When you occupy real Shi, you often don't need to fight — the greatest victories are bloodless, because the opponent sees they have no escape and surrenders. The win is a side effect of position, not of a specific hostile action.
This maps onto what's called maneuver warfare — flexibility to move in multiple directions from a position of latent advantage, rather than committing early to one line of attack. Napoleon, likely among the first Western strategists to have read Sun Tzu, built Napoleonic warfare around this logic.
Distinct from but paired with Strategic Depth: Causal-Chain Thinking (Three-Dimensional Chess) — Shi describes the shape of a strong position; causal-depth thinking is the mental work needed to see far enough ahead to build one.