So Gerbert wrote from Rheims, himself a chief intriguer in a city full of treason.
Gerbert was a power making for letters. The best scholars sat at his feet; he was an inspiration at the Courts of the second and third Ottos, who loved learning and died so young; and the great school of Chartres, under the headship of his pupil Fulbert, was the direct heir to his instruction. At Rheims, where he taught so many years, he left to others the elementary instruction in Latin. A pupil, Richer, who wrote his history, speaks of courses in rhetoric and literature, to which he introduced his pupils after instructing them in logic:
“When he wished to lead them on from such studies to rhetoric, he put in practice his opinion that one cannot attain the art of oratory without a previous knowledge of the modes of diction which are to be learned from the poets. So he brought forward those with whom he thought his pupils should be conversant. He read and explained the poets Virgil, Statius, and Terence, the satirists Juvenal and Persius and Horace, also Lucan the historiographer. Familiarized with these, and practised in their locutions, he taught his pupils rhetoric. After they were instructed in this art, he brought up a sophist, to practise them in disputation, so that practised in this art as well, they might seem to argue artlessly, which he deemed the height of oratory.”[366]
So Gerbert used the classic poets in teaching rhetoric, and doubtless the great prose writers too, with whom he was familiar. Following Cicero’s precept that the orator should be a proficient reasoner, he prepared his young rhetoricians by a course in logic, and completed their discipline with exercises in disputation.
Richer also speaks of Gerbert’s epoch-making mathematical knowledge.[367] In arithmetic he improved the current methods of computation; in geometry he taught the traditional methods of measurement descended from the Roman surveyors, and compiled a work from Boëthius and other sources. For astronomy he made spheres and other instruments, and in music his teaching was the best obtainable. In none of these provinces was he an original inventor; nor did he exhaust the knowledge had by men before him. He was, however, the embodiment of mediaeval progress, in that he drew intelligently upon the sources within his reach, and then taught with understanding and enthusiasm. Richer’s praise is unstinted:
“He began with arithmetic; then taught music, of which there had long been ignorance in Gaul.... With what pains he set forth the method of astronomy, it may be well to state, so that the reader may perceive the sagacity and skill of this great man. This difficult subject he explained by means of admirable instruments. First he illustrated the world’s sphere by one of solid wood, the greater by the less. He fixed it obliquely as to the horizon with two poles, and near the upper pole set the northern constellations, and by the lower one those of the south. He determined its position by means of the circle called by the Greeks orizon and by the Latins limitans, because it divides the constellations which are seen from those which are not. By his sphere thus fixed, he demonstrated the rising and setting of the stars, and taught his disciples to recognize them. And at night he followed their courses and marked the place of their rising and setting upon the different regions of his model.”
The historian passes on to tell how Gerbert with ingenious devices showed on his sphere the imaginary circles called parallels, and on another the movements of the planets, and on still another marked the constellations of the heavens, so that even a beginner, upon having one constellation pointed out, could find the others.[368]
In the province of philosophy, Gerbert’s labours extended little beyond formal logic, philosophy’s instrument. He could do no more than understand and apply as much of Boëthius’s rendering of the Aristotelian Organon as he was acquainted with. Yet he appears to have used more of the Boëthian writings than any man before him, or for a hundred and fifty years after his death. Richer gives the list. Beyond this evidence, curious testimony is borne to the nature of Gerbert’s dialectic by Richer’s account of a notable debate. The year was 980, when the fame of the brilliant young scholasticus of Rheims had spread through Gaul and penetrated Germany. A certain master of repute at Magdeburg, named Otric, sent one of his pupils to report on Gerbert’s teaching, and especially as to his method of laying out the divisions of philosophy as “the science of things divine and human.” The pupil returned with notes of Gerbert’s classification, in which, by error or intention, it was made to appear that he subordinated physics to mathematics, as species to genus, whereas, in truth, he made them of equal rank. Otric thought to catch him tripping, and so managed that a disputation was held between them at a time when Adalberon and Gerbert were in Italy with the Emperor Otto II. It took place in Ravenna. The emperor, then nineteen years of age, presided, there being present many masters and dignitaries of the Church. Holding in his hand a tablet of Gerbert’s alleged division of the sciences, His Majesty opened the debate:
“Meditation and discussion, as I think, make for the betterment of human knowledge, and questions from the wise rouse our thoughtfulness. Thus knowledge of things is drawn forth by the learned, or discovered by them and committed to books, which remain to our great good. We also may be incited by certain objects which draw the mind to a surer understanding. Observe now, that I am turning over this tablet inscribed with the divisions of philosophy. Let all consider it carefully, and each say what he thinks. If it be complete, let it be confirmed by your approbation. If imperfect, let it be rejected or corrected.
“Then Otric, taking it before them all, said that it was arranged by Gerbert, and had been taken down from his lectures. He handed it to the Lord Augustus, who read it through, and presented it to Gerbert. The latter, carefully examining it, approved in part, and in part condemned, asserting that the scheme had not been arranged thus by him. Asked by Augustus to correct it, he said: ‘Since, O great Caesar Augustus, I see thee more potent than all these, I will, as is fitting, obey thy behest. Nor shall I be concerned at the spite of the malevolent, by whose instigation the very correct division of philosophy recently set forth so lucidly by me, has been vitiated by the substitution of a species. I say then, that mathematics, physics, and theology are to be placed as equals under one genus. The genus likewise has equal share in them. Nor is it possible that one and the same species, in one and the same respect, should be co-ordinate with another species and also be put under it as species under a genus.’”