star, god of literature
奎 centers on a specific star or constellation, and by extension the god of literature associated with it. The two meanings are linked through traditional Chinese astrology where this star governs literary pursuits.
奎 combines 大 (big) and 圭 (a jade tablet or scepter). Historically, it is the name of a constellation in Chinese astronomy, and the character likely represents the shape of the stars or a mythological association. The exact origin of the combination is uncertain.
Imagine a giant (大) jade tablet (圭) in the sky, marking the position of the star that oversees literature. The big tablet represents the authority of the god of literature.
For ケイ, picture the star shining like a bright letter K in the sky: K -> ケイ, and the god of literature uses it to write stories.
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