One man whom I know holds that all popes since Pius X were heretics. Whole groups maintain that all popes after Vatican II are heretics, even John Paul II. He invited leaders of other religions to Assisi to pray together, but he failed to evangelize them or insist in uniqueness of Catholicism. At Vatican I, several notable figures did not accept the infallibility doctrine. The Reformation itself mostly declared all popes heretical back to Peter. Pope Paul III excommunicated Henry VIII precisely over the question of the indissolubility of marriage. The Eastern Orthodox have rejected the papal position for centuries....