Of this measure, John Gerson, a stout doctor, was the author of the champion. The proceedings of the university of Paris and the Gallican church were often prompted by his advice, and are copiously displayed in his theological writings, of which Le Clerc (Bibliotheque Choisie, tom. x. p. 1 - 78) has given a valuable extract. John Gerson acted an important part in the councils of Pisa and Constance.