It was to the reformation of this corrupt Latin by a return to classical models, and to the more general spread of culture, especially among clergy and nobles, that the Carolingian revival addressed itself. The movement was essentially practical and conservative. Alcuin (735-804), who was Charlemagne's educational adviser and chief executive officer in scholastic matters, was probably the best scholar of his time, and himself loved the classical writings with which he was acquainted; but the text-books he wrote were but imperfect summaries of existing compendia, and the intellectual condition of his pupils forbade a very generous literary diet even had he thought it desirable, of which there is some doubt. The most valuable outcome of the movement was the establishment of the palace school, and of bishops' schools and monastic schools throughout the empire. Of these the latter were the most important, and each of the chief monasteries had from the time of Charlemagne an external school for pupils not proposing to enter the order as well as an internal school for novices. Thus, the educational system north of the Alps was pre-eminently ecclesiastical in its organization and profoundly religious in its aims. For two centuries the new intellectual life was obscured by the troubled times which followed the death of Charlemagne, but the learning which the Carolingian revival had restored was preserved here and there in cathedral and monastic schools, and the sequence of well-educated ecclesiastics was never altogether interrupted. The medieval curriculum. The scope of that learning was comprised within the seven liberal arts and philosophy, on the secular side, together with some dogmatic instruction in the doctrines of the Church, the early fathers, and the Scriptures. Theology was as yet not organized into a philosophical system: that was the great work the middle ages had to perform. The seven liberal arts (divided into the _Trivium_--grammar, dialectic, rhetoric; and the more advanced _Quadrivium_--geometry, arithmetic, music, astronomy) were a legacy from old Roman education through the transition centuries. They appear in the _Disciplinarum libri IX._ of Varro in the 2nd century B.C., where are added to them the more utilitarian arts of medicine and architecture. But they reached the middle ages chiefly through the summaries of writers in the transition centuries, of which the best known were the _De nuptiis Philologiae et Mercurii_ of the Neo-platonist Martianus Capella, who wrote probably early in the 5th century; the _De artibus ac disciplinis liberalium litterarum_ of the Christian Cassiodorus (468-562); and the _Etymologiarum libri XX._ of St Isidore of Seville (570-636).