Albrecht Dürer's mysterious engraving Melencolia I (Figure 1) has always intrigued both art critics and mathematicians. Among art critics, according to Campbell Dodgson [1], “The literature on the Melancholia is more extensive than that on any other engraving by Dürer” (he adds “the statement would probably remain true if the last two words were omitted”). Mathematicians, if disconcerted by the association between mathematics and melancholy, have been fascinated by the objects appearing in the print, such as the polyhedron occurring on the left of the engraving and—the subject of this note—the magic square in the upper right-hand corner (Figure 2).