sài wēng shī mǎ , yān zhī fēi fú
塞翁失马,焉知非福
A loss, no bad thing
翁：an old man's name
失：loss
马：horse
焉：how can
知：know
非：isn't
福：fortune
In ancient times at the north frontier lived an old man. His horse ran across the Great wall to the habitat of Hu ethnicity. His fellow villagers consoled him that it might not have been a misfortune. A few days later, the lost horse headed back with a group of Hu people. Everyone went to congratulate him, but the old man thought otherwise. He kept many good horses at home and his son fonded riding on the horseback to frolic around. The other day his son broke his own leg from falling off a horse. Again people came to comfort him, but the old man had a different view. In time his son evaded the warfare owing to his wounded leg.