Poverty by degrees turned his brain; but a long time passed before it was perceived. The first proof that he gave of it was at the house of Madame Pelot, widow of the Chief President of the Rouen parliament. Playing at brelan one evening, she offered him a stake, and because he would not accept it bantered him, and playfully called him a poltroon. He said nothing, but waited until all the rest of the company had left the room; and when he found himself alone with Madame Pelot, he bolted the door, clapped his hat on his head, drove her up against the chimney, and holding her head between his two fists, said he knew no reason why he should not pound it into a jelly, in order to teach her to call him poltroon again. The poor woman was horribly frightened, and made perpendicular curtseys between his two fists, and all sorts of excuses. At last he let her go, more dead than alive. She had the generosity to say no syllable of this occurrence until after his death; she even allowed him to come to the house as usual, but took care never to be alone with him.
One day, a long time after this, meeting, in a gallery, at Fontainebleau, M. de Courtenay, La Vauguyon drew his sword, and compelled the other to draw also, although there had never been the slightest quarrel between them. They were soon separated and La Vauguyon immediately fled to the King, who was just then in his private closet, where nobody ever entered unless expressly summoned. But La Vauguyon turned the key, and, in spite of the usher on guard, forced his way in. The King in great emotion asked him what was the matter. La Vauguyon on his knees said he had been insulted by M. de Courtenay and demanded pardon for having drawn his sword in the palace. His Majesty, promising to examine the matter, with great trouble got rid of La Vauguyon. As nothing could be made of it, M. de Courtenay declaring he had been insulted by La Vauguyon and forced to draw his sword, and the other telling the same tale, both were sent to the Bastille. After a short imprisonment they were released, and appeared at the Court as usual.