harmony of beauty and substance; balance of looks and character; refinement and simplicity in harmony
A yojijukugo describing an ideal state where outward refinement (文) and inner substance (質) are perfectly balanced. Sense 2 emphasizes the harmony between elegance and plainness. Rare in everyday speech; mostly found in literary or philosophical contexts.
His writing is a perfect balance of beauty and substance, where elegant style and deep content are in harmony.