必

The heart radical supplies the curving body and three dots that frame the character. 必 was historically analysed as a heart pierced by a marker, conveying 'certain, must' — what the heart insists on. The radical anchors the character for dictionary lookup despite its own complex pierced silhouette.

A single diagonal stroke cuts across the heart-body, acting as the locator marker that originally distinguished 必 from plain 心. Reading the picture: the heart held by a definite line — what one is sure of, what must be.