Once there came to the Emperor a merchant with many gems and jewels, and begged him to purchase some.
The Emperor asked of Virgil, who was present:
“Which is the very best of all these stones?”
Virgil replied:
“Let them all remain for a time in the light of the sun, and I will tell you which is the gem of them all.”
This was done, and after a time a fly alighted on one.
“This is the gem of greatest value,” said Virgil.
“But it is really hardly worth a crown,” replied the merchant.
“And yet it is worth all the rest put together,” answered Virgil; “for it increases marvellously the intellect or understanding, and thereby one can win with it the love of whom he will.”
“Very well,” said the Emperor, “I will buy it, and find by experience whether it can increase wit whereby we gain hearts.”