This incident, becoming known, gave rise to the proverb, still used in relation to people of dull wits⁠— Tu sei piu tondo che l’O di Giotto ; the significance of which consists in the double meaning of the word ‘tondo,’ which is used in the Tuscan for slowness of intellect and heaviness of comprehension, as well as for an exact circle. The proverb has besides an interest from the circumstance which gave it birth.⁠ ⁠… “It is said that Giotto, when he was still a boy, and studying with Cimabue, once painted a fly on the nose of a figure on which Cimabue himself was employed, and this so naturally, that, when the master returned to continue his work, he believed it to be real, and lifted his hand more than once to drive it away before he should go on with the painting.” Boccaccio, Decameron , VI 5, tells this tale of Giotto:⁠— “As it often happens that fortune hides under the meanest trades in life the greatest virtues, which has been proved by Pampinea; so are the greatest geniuses found frequently lodged by Nature in the most deformed and misshapen bodies, which was verified in two of our own citizens, as I am now going to relate.