日rì

日 (rì), representing the sun or simply "day," is one of the most ancient and unchanged pictographs in all of Chinese script—a simple circle bisected by a horizontal line, just as it appeared on oracle bones three thousand years ago. This unassuming character serves as a critical building block in dozens of compound characters related to time, light, and warmth, from 早 (morning) to 明 (bright) to 时 (time). Its simplicity is its strength; the visual of the sun was so perfectly captured that centuries of script evolution saw no need to alter its essential form.