During the Southern and Northern Dynasties (420-589 AD), there lived a renowned painter named Zhang Sengyao. One day, while visiting a temple, he painted four magnificent dragons on a wall, yet deliberately left out their eyes.
Bystanders found this peculiar and inquired about the omission. Zhang explained, "The eyes are the soul of a dragon. If I paint them in, the dragons will come to life and fly away." Skeptical of his claim, the onlookers urged him to proceed.
Zhang then picked up his brush and added eyes to two of the dragons. The moment he finished, thunder rumbled, and the two dragons soared into the sky, leaving the other two eyeless dragons forever fixed on the wall.
This idiom, "Adding the Finishing Touch," illustrates how a single, well-placed detail—be it a brushstroke in painting, a sentence in writing, or a word in speech—can dramatically enhance and perfect the entire work.