Brothers, Tuscans by birth, employed at the court of Constantinople under the Emperor Manuel I (Comnenus, 1143-1180). Their name is spelled in various ways: Ætherianus, Heterianus, Eretrianus, etc. Leo is of little importance. We know from his brother (Adv. Graec. I, 20) that he was "occupied in translating the imperial letters", evidently an interpreter for Latin correspondence. Hugh, who does not seem to have held any official post at court, but was a very learned theologian, had many opportunities of discussing the questions at issue between the Orthodox and Catholics (so he tells us: Adv. Graec., Praef. I., Migne, P.L., CCII, 165). As a result of these disputes he wrote a work in three books: "De haeresibus quas Graeci in Latinos devolvunt, sive quod Spiritus Sanctus ex utroque Patre et Filio procedit" (P.L., CCII, generally quoted as "Adv. Graecos"). This work, the first exhaustive and scientific defence of the Filioque , was composed in both languages, Latin and Greek. The author sent copies to the Orthodox Patriarch of Antioch, Aimerikos, and to Pope Alexander III (1159-1181), whose letter of acknowledgment is still extant (Ep. xlix, Baronius, an. 1177, n. 37, 38). Hugh Etherianus by this treatise obtains a very important place among Catholic controversialists against the Eastern Church. It appears that the emperor, who was well disposed towards Latins, had suggested that he should write it, having asked him whether they have "any authorities of saints who say that the Holy Ghost proceeds from the Son" (ib., Praef. I, CCII, col. 165). Hugh had used his knowledge of Greek and his opportunities of studying their Fathers so well that he was able to produce texts from nearly all the recognized authorities on both sides. He quotes especially Sts. Athanasius, Cyril of Alexandria, Basil, Gregory Nazianzen, Chrysostom, John Damascene, etc. From the Latins he produced witnesses from Sts. Augustine, Jerome, Gregory I, Ambrose, Hilary. He was also well acquainted with the writings of his adversaries and quotes Photius, Nicetas of Thessalonica, Theophylactus of Achrida, etc. The Latin version is very corrupt and untrustworthy. There are also some incorrect expressions noted by the later editors, such as that God the Father is the cause of the Son (this is a concession to the Greeks that was, however, tolerated by the Council of Florence ; Denzinger, Enchiridion, n. 586). Nevertheless, since it was written this work has been the foundation of nearly all Latin controversy with the Greeks. St. Thomas Aquinas used it for his "Opusc. I, contra errores Graecorum" and Cardinal Bessarion refers to it with great praise (Ep. ad Alex., P.L., CLXI, 328). Hugh Etherianus also wrote a treatise "De regressu animarum ab inferis", in answer to a petition of the clergy of Pisa, and (probably) a short work "De Graecorum malis consuetudinibus". A "Liber de immortali Deo", written by him, is lost.

The Catholic Encyclopedia is the most comprehensive resource on Catholic teaching, history, and information ever gathered in all of human history. This easy-to-search online version was originally printed in fifteen hardcopy volumes.

Designed to present its readers with the full body of Catholic teaching, the Encyclopedia contains not only precise statements of what the Church has defined, but also an impartial record of different views of acknowledged authority on all disputed questions, national, political or factional. In the determination of the truth the most recent and acknowledged scientific methods are employed, and the results of the latest research in theology, philosophy, history, apologetics, archaeology, and other sciences are given careful consideration.

No one who is interested in human history, past and present, can ignore the Catholic Church, either as an institution which has been the central figure in the civilized world for nearly two thousand years, decisively affecting its destinies, religious, literary, scientific, social and political, or as an existing power whose influence and activity extend to every part of the globe. In the past century the Church has grown both extensively and intensively among English-speaking peoples. Their living interests demand that they should have the means of informing themselves about this vast institution, which, whether they are Catholics or not, affects their fortunes and their destiny.

Copyright © Catholic Encyclopedia. Robert Appleton Company New York, NY. Volume 1: 1907; Volume 2: 1907; Volume 3: 1908; Volume 4: 1908; Volume 5: 1909; Volume 6: 1909; Volume 7: 1910; Volume 8: 1910; Volume 9: 1910; Volume 10: 1911; Volume 11: - 1911; Volume 12: - 1911; Volume 13: - 1912; Volume 14: 1912; Volume 15: 1912

Catholic Online Catholic Encyclopedia Digital version Compiled and Copyright © Catholic Online