ive a range from about the middle of May to about the middle of June, so that the 8th is certainly too early. This is the date given by Boccaccio, who is generally followed, though he makes a blunder in saying, sedendo Urbano quarto nella cattedra di San Pietro, for Urban died in October, 1264.
Some, misled by an error in a few of the early manuscript copies of the Divina Commedia, would have him born five years earlier, in 1260.
According to Arrivabene,
Secolo di Dante, Udine edition of 1828, Vol.
III. Part I. p. 578. Sansovino was the first to confirm Boccaccio's statement by the authority of the poet himself, basing his argument on the first verse of the Inferno,—
Nel mezzo del cammin di nostra vita; the average age of man having been declared by the Psalmist to be seventy years, and the period of the poet's supposed vision being unequivocally fixed at 1300.
Arrivabene, however, is wrong.
Boccaccio makes precisely the same reckoning in the first note of his Commentary