A man was arguing and boasting that he knew many and various tricks. Another among the bystanders said: “I know how to play a trick which will make whomsoever I like pull off his breeches.” The first man— the boaster—said: “You won’t make me pull off mine, and I bet you a pair of hose on it.” He who proposed the game, having accepted the offer, produced breeches and drew them across the face of him who bet the pair of hose and won the bet .
A man said to an acquaintance: “Your eyes are changed to a strange colour.” The other replied: “It often happens, but you have not noticed it.” “When does it happen?” said the former. “Every time that my eyes see your ugly face, from the shock of so unpleasing a sight they suddenly turn pale and change to a strange colour.”
A man said to another: “Your eyes are changed to a strange colour.” The other replied: “It is because my eyes behold your strange ugly face.”
A man said that in his country were the strangest things in the world. Another answered: “You, who were born there, confirm this as true, by the strangeness of your ugly face.”
[Footnote: The joke turns, it appears, on two meanings of trarre and is not easily translated.]
Taken from The Notebooks of Leonardo da Vinci edited by Jean Paul Richter, 1880.