The Old Man Lost His Horse
An old man living at the frontier loses his horse, and his neighbours come to console him. Months later the horse returns, leading others — and the neighbours come to congratulate him. His son rides one of the new horses, falls, and shatters his leg; the neighbours console. Then war comes to the frontier, and the able-bodied young men are conscripted, and nearly all of them die — and the boy with the ruined leg is passed over, and lives.
The story appears in the eighteenth chapter of the Huainanzi, the second-century-BCE compendium — the chapter concerned with the world of human affairs. Most people meet it as the proverb it later became, which compresses the whole sequence into a question: how do you know it is not good fortune? The text itself goes further than its proverb. It does not ask whether you can know. It states that blessing turns to disaster and disaster to blessing, that the transformations never come to an end — and that their depths cannot be fathomed.
— Huainanzi, ch. 18, “In the World of Man,” 2nd c. BCE. Retold rather than quoted: the chapter’s closing lines are described here because no published English rendering of them has been verified against a primary edition. Working source: Larre, Robinet & Rochat de la Vallée, Les grands traités du Huainan zi (Institut Ricci, 1993), ch. 18. The four-character proverb the story became is its descendant, not its source.