In the Renaissance world, artists and architects often composed their canvasses and buildings according to numerical and musical harmonies. Many major poets, including Dante, Spenser and Milton, did the same in their work. Shakespeare's poems have been analysed for their numerology, but surprisingly his plays have not. Sylvia Eckersley had studied scene-symmetry in Shakespeare's plays, and was struck by the exact middle lines of Macbeth as numbered on a First Folio edition: See they encounter th...