It is precisely his sympathy with Catholicism on the religious side, and his alienation from its intellectual method, which makes Newman’s apologetic such a two-edged weapon.  In attempting to defend Catholicism, he has gone far to explain it.  To the historian, there is no great mystery about the growth and success of the Western Catholic Church.  Christianity was already a syncretistic religion in the second century.  Like the other forms of worship with which it competed for the popular favour, it contained the necessary elements of mystery-cult, of ethical rule, of social brotherhood, and of personal devotion.  But besides many genuine points of superiority, it had a decisive advantage over the religions of Isis and Mithra in the exclusiveness and intolerance which it derived from the Jewish tradition.  When the failure of the last persecution forced the Empire to make a concordat with the Church, the transformation of the federated but autonomous Christian communities into a centralised theocratic despotism, claiming secular as well as spiritual sovereignty, was only a matter of time.  It was inevitable, just as the principate of Augustus and the sultanate of Diocletian were inevitable; but there is nothing specially divine or glorious about any of these phases of human evolution.  The revolt of Northern Europe in the sixteenth century was equally inevitable; and so is the alienation of enlightened minds from the Roman Church at the present day.  Newman shows with great force and ingenuity that all the developments in the Roman system which Protestantism rejects as later accretions were natural and necessary.  But this only means that the Catholic Church, in order to live, was compelled to adapt itself to the prevailing conditions of human culture in the countries where it desired to be supreme.  The argument, so far as it goes, tells against rather than in favour of any special supernatural character belonging to that institution.  And if the ‘orbis terrarum,’ which once gave its verdict in favour of Latin Catholicism, is now disposed to reverse its decision, how, on Newman’s principle, can its right to do so be denied?  The true reasons for the strength and vitality which the Roman Church still retains are not difficult to find.  Its system possesses an inner consistency, which is dearly purchased by neglecting much that should enter into a large and true view of the world, but which guarantees to those who have once accepted it an untroubled calm and assurance very acceptable to those who have been tossed upon a sea of doubt.  It surrounds itself with an impenetrable armour by persuading its adherents that all moral and intellectual scruples, in matters where Holy Church has pronounced its verdict, are suggestions of the Evil One, to be spurned like the prickings of sensuality.  It has succeeded, by long experience, in providing satisfaction for nearly all the needs of the average man, and for all the needs of the average woman.  In particular,