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Card #c666IR // #c666Synthesis

Musashi's ninth precept: 'Do nothing which is of no use.' The individual's version of Sun Tzu's cost-awareness: strip every action that doesn't serve the fight. Economy is not stinginess — it is the discipline of keeping the spirit uncluttered and the effort undivided.

— In our words · Source: The Book of Five Rings (Miyamoto Musashi)

[Use when]

Use to audit a plan or a day: which actions are of no use, and what do they cost in attention even when they cost nothing in money?

[Why it matters]

Sun Tzu's ch. 2 is a sustained argument against waste — 'there is no instance of a country having benefited from prolonged warfare,' forage the enemy, use captured chariots. Musashi compresses the same principle into one line for one person. The agree shows economy scales from the state down to the single swordsman.

Related principles

#c474There is no instance of a country having benefited from prolonged warfare. Though we have heard of stupid haste in war, cleverness has…A campaign, project, or conflict is drifting past its planned end and everyone is calling it patience.

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