On another occasion, M. de Coislin went to the Sorbonne to listen to a thesis sustained by the second son of M. de Bouillon. When persons of distinction gave these discourses, it was customary for the Princes of the blood, and for many of the Court, to go and hear them. M. de Coislin was at that time almost last in order of precedence among the Dukes. When he took his seat, therefore, knowing that a number of them would probably arrive, he left several rows of vacant places in front of him, and sat himself down. Immediately afterwards, Novion, Chief President of the Parliament, arrived, and seated himself in front of M. de Coislin. Astonished at this act of madness, M. de Coislin said not a word, but took an arm-chair, and, while Novion turned his head to speak to Cardinal de Bouillon, placed that arm-chair in front of the Chief President in such a manner that he was as it were imprisoned, and unable to stir. M. de Coislin then sat down. This was done so rapidly, that nobody saw it until it was finished. When once it was observed, a great stir arose. Cardinal de Bouillon tried to intervene. M. de Coislin replied, that since the Chief President had forgotten his position he must be taught it, and would not budge. The other presidents were in a fright, and Novion, enraged by the offence put on him, knew not what to do. It was in vain that Cardinal de Bouillon on one side, and his brother on the other, tried to persuade M. de Coislin to give way. He would not listen to them. They sent a message to him to say that somebody wanted to see him at the door on most important business. But this had no effect. "There is no business so important," replied M. de Coislin, "as that of teaching M. le Premier President what he owes me, and nothing will make me go from this place unless M. le President, whom you see behind me, goes away first." At last M. le Prince was sent for, and he with much persuasion endeavoured to induce M. de Coislin to release the Chief President from his prison. But for some time M. de Coislin would listen as little to M. le Prince as he had listened to the others, and threatened to keep Novion thus shut up during all the thesis. At length, he consented to set the Chief President free, but only on condition that he left the building immediately; that M. le Prince should guarantee this; and that no "juggling tricks" (that was the term he made use of), should be played off to defeat the agreement. M. le Prince at once gave his word that everything should be as he required, and M. de Coislin then rose, moved away his arm-chair, and said to the Chief President, "Go away, sir! go away, sir! "Novion did on the instant go away, in the utmost confusion, and jumped into his coach. M. de Coislin thereupon took back his chair to its former position and composed himself to listen again.