始计
War is too consequential to enter blindly — weigh the five fundamentals and reckon the odds before the first move, because all warfare rests on deception.
What this chapter says
The opening chapter insists that war, deciding a state's life or death, must never be undertaken without cold assessment. Sun Tzu names five fundamentals to weigh — the Moral Law (道, whether the people are in harmony with their ruler), Heaven (天, seasons and timing), Earth (地, terrain and distance), the Commander (将, his virtues), and Method and discipline (法, organisation). Compare both sides across these and the outcome can be calculated in the temple before a single battle: whoever scores more is more likely to win. And because deception governs everything — appear weak when strong, near when far — the plan is only the beginning; execution turns on misdirection and striking where the enemy is unready.
Key lines
Applied today
Enter a market only after honestly scoring both sides on the deciding factors — team, timing, positioning, resources. The competitor who has done more of this cold 'temple calculation' before acting usually wins.
Before you commit, map which side is stronger on each point that matters. Most contests are decided by preparation, not the clash — and letting the other side misread your position is part of the work.