The question of heresy is easily settled by the way of authority. We have only to inquire, therefore, whether the Holy See has ever condemned the adherents of the schism begun by Photius and renewed by Michael Cerularius, of heresy as well as schism, and whether the standard authors in theology consider them as heretics in view of their ecclesiastical position and in virtue of general principles, although no formal judgment has been pronounced by the Holy See. It is certain that no such formal sentence has ever been pronounced by the Holy See. The Nestorian and Monophysite sects of the East have been formally condemned as heretical. But the _soi-disant_ Orthodox Church likewise condemns these and all other heretical sects condemned by the Roman Church before the time of the schism. At the Council of Florence the Greeks were not judged to have professed any heresy, the Council of Trent was specially careful to abstain from any such condemnation, and the Council of the Vatican equally refrained from it. The same is true of all the official pronouncements of the popes. In the exercise of practical discipline, when it is a question of reconciling Greeks, whether they are in holy orders or laymen, they are treated as schismatics, but not as heretics. Theologians also, in treating of the doctrine of the several national churches in communion with the schismatical patriarchate of Constantinople, which they hold in common as their profession of faith, regard it as orthodox, conformed to the doctrine of the Catholic Church, and consequently free from any mixture of heresy. The only doctrines in regard to which any one could suppose the Greek Church to be heretical are the procession of the Holy Spirit from the Son, and the supreme, infallible authority of the Pope. The Greek Church has never, by any solemn, synodical act, denied the procession of the Holy Spirit from the Son. The omission of the _Filio-que_ from the Creed is not in itself equivalent to such a denial, and the Roman Church has never required the Orientals to insert it as a condition of communion. Neither has the Greek Church ever by any solemn act denied the supremacy and infallibility of the Pope. The liturgical books, and specifically those of the Russian Church, contain abundant testimonies to the Catholic doctrine on this head. The heretical doctrines of individuals, whether prelates, priests, or laymen, are therefore their own personal heresies, and not the doctrine of the public formularies of faith, which remain just what they were at the time of the separation. The only conciliar decrees of a dogmatic character which have been enacted since that time by a synod which could be regarded as representing the so-called Orthodox Church are those of the Synod of Bethlehem, in which the principal heresies of Protestantism are condemned. There is only one essential vice, therefore, in the constitution of the Russo-Greek Church