Aesop

… “Don't let your special character and values, the secret that you know and no one else does, the truth - don't let that get swallowed up by the great chewing complacency.”
Aesop

210. AESOP AND THE ATHLETE
… Aesop, that wise man from Phrygia, once saw a winning athlete who was making extravagant boasts, so he asked whether the man's opponent had been more powerfully built. The athlete replied, 'Watch what you're saying! I was much stronger than he was.' 'You fool!' said Aesop. 'What kind of prize do you deserve if you were the stronger athlete and simply triumphed over an inferior opponent? You might have earned my grudging admiration if your opponent had in fact been superior to you in strength, so that you had to defeat him by means of your exceptional athletic prowess.'
Source: Aesop's Fables. A new translation by Laura Gibbs. Oxford University Press (World's Classics): Oxford, 2002.

521. HERMES AND THE ARABS
… Hermes filled a cart with lies and dishonesty and all sorts of wicked tricks, and he journeyed in this cart throughout the land, going hither and thither from one tribe to another, dispensing to each nation a small portion of his wares. When he reached the land of the Arabs, so the story goes, his cart suddenly broke down along the way and was stuck there. The Arabs seized the contents of the cart as if it were a merchant's valuable cargo, stripping the cart bare and preventing Hermes from continuing on his journey, although there were still some people he had not yet visited. As a result, Arabs are liars and charlatans, as I myself have learned from experience. There is not a word of truth that springs from their lips.
Source: Aesop's Fables. A new translation by Laura Gibbs. Oxford University Press (World's Classics): Oxford, 2002.