We have already touched upon some of the characteristics of domestic architecture in referring to the mediæval castle. This was rather a stronghold than a home,--strength and inaccessibility were its main requirements. The walls were many feet thick and the tiny windows, often hardly more than slits in the massive walls, the stone floors, the great bare halls warmed only by large fireplaces, suggest nothing of the comfort of a modern household. At the same time they imply a simplicity of taste and manners and a hardihood of body which we may well envy. [Sidenote: The schools before the eleventh century.] 103. On turning from the language and books of the people and the art of the period to the occupations of the learned class, who carried on their studies and discussions in Latin, we naturally inquire where such persons obtained their education. During the long centuries which elapsed between the time when Justinian closed the government schools and the advent of Frederick Barbarossa, there appears to have been nothing in western Europe, outside of Italy and Spain, corresponding to our universities and colleges. Some of the schools which the bishops and abbots had established in accordance with Charlemagne's commands were, it is true, maintained all through the dark and disorderly times which followed his death. But the little that we know of the instruction offered in them would indicate that it was very elementary, although there were sometimes noted men at their head. [Sidenote: Abelard, d. 1142.] About the year 1100 an ardent young man named Abelard started out from his home in Brittany to visit all the places where he might hope to receive instruction in logic and philosophy, in which, like all his learned contemporaries, he was especially interested. He reports that he found teachers in several of the French towns, particularly in Paris, who were attracting large numbers of students to listen to their lectures upon logic, rhetoric, and theology. Abelard soon showed his superiority to his teachers by defeating them several times in debate. Before long he began lecturing on his own account, and such was his success that thousands of students flocked to hear him. [Sidenote: Abelard's _Yea and Nay_.]