The proof that dogmas are not immutable lies in the fact that they have a history. That history is as full of conflicts, controversies, revolutions, as the history of philosophy.... One Church has said of its dogmas what a Jesuit General said of his Order: _sint ut sunt aut non sint_! It is an illusion. Momentarily arrested at one point, the movement begins again at another. In one half of Christendom, and certainly the most living half, criticism of dogma has never ceased since the sixteenth century. Even in the bosom of the Catholic Church, its most skilful advocates, the Moehlers and the Newmans, unable to deny that Catholicism is not to-day what it was in the first centuries, have made this strange concession to history; they have applied to dogmas the theory of development. At Paris in 1682 the dogma of the infallibility of the Bishop of Rome would have been condemned as an error. Since 1870 the orthodoxy of 1682 has become the gravest of heresies. There is no fiction more evident than that of the immutability of dogmas, whether in the Catholic or in the Protestant Churches. Like all other manifestations of life, they have an evolution as natural as it is inevitable. The proof that dogmas are not religion, and that criticism does not kill them but transforms them, will appear in what I now proceed to say. 2. _The Two Elements in Dogma; and its Historical Evolution_ Dogma is the language spoken by faith. In it there are two elements: a mystical and practical element, the properly religious element; this is the living and fruitful principle of dogma: then there is an intellectual or theoretical element, a judgment of mind, a philosophical proposition serving at once as an envelope and as an expression of religion.