From Jame Branch Cabell’s Figures of Earth, the first (narrative) volume of Cabell’s Biography of the Life of Manuel series.
Thereafter the florid young Count of Poictesme rode east, on a tall dappled horse, and a retinue of six lackeys in silver and black liveries came cantering after him, and the two foremost lackeys carried in knapsacks, marked with a gold coronet, the images which Dom Manuel had made. A third lackey carried Dom Manuel’s shield, upon which were emblazoned the arms of Poictesme. The black shield displayed a silver stallion which was rampant in every member and was bridled with gold, but the ancient arms had been given a new motto.
“What means this Greek?” Dom Manuel had asked.
“Mundus decipit, Count,” they told him, “is the old pious motto of Poictesme: it signifies that the affairs of this world are a vain fleeting show, and that terrestrial appearances are nowhere of any particular importance.”
“Then your motto is green inexperience,” said Manuel, “and for me to bear it would be black ingratitude.”
So the writing had been changed in accordance with his instructions, and it now read Mundus vult decipi.
The change to the Latin is from ‘the world deceives/beguiles’ to ‘the world wishes to be deceived/beguiled.’