Detail of the Three Graces from the Loggia of Cupid and Psyche by Raphael and His Workshop.
We use threes in art to define structures like primary, secondary and tertiary colors on a color wheel. Sir Isaac Newton developed the first color wheel in 1666. The three Greek column classifications are Doric, Ionic, and Corinthian.
Detail of the Three Graces from the Loggia of Cupid and Psyche by Raphael and His Workshop.
Detail of The Three Graces from Wedding of Cupid and Psyche by Raphael.
Detail Showing Three Virgin Saints from the Apse Mosaic of San Paolo fuori le Mura by Edward Burne-Jones.