Dante, like most people of his time, believed that some numbers had mystical meanings and associations. He designed the structure of his poem using a series of mystical numbers:
THREE: The number of the Holy Trinity: God the Father, the Son, and the Holy Ghost; The number of parts of the Divine Comedy: Inferno, Purgatorio, Paradiso; The number of lines in each verse of each canto; The number of divisions of Hell; The number of days required for Dante's journey through Hell.
NINE: A multiple of three; the number of circles in Hell.
TEN: The perfect number is the nine circles of Hell plus the vestibule.
THIRTY-THREE: A multiple of three; the number of cantos in each part.
NINETY-NINE: The total number of cantos plus Canto I, The Introduction.
ONE HUNDRED: A multiple of ten; considered by Dante to be the perfect number.
