After the society had been in existence some forty years, Claudius Aquaviva became its General Superior. He at once began the study of the educational problem, using all the resources of his office in obtaining information, and employing his executive ability in producing an improved method of study. A committee of twelve most eminent churchmen was appointed in 1581 to study the question, and three years later a commission of six, representing different countries, began the labor of preparing a course of study. Their work, called the _Ratio Studiorum_,[70] completed in 1599, has remained, with some modifications, the guide of Jesuit institutions of learning. =Emulation=.--Emulation was employed to stimulate pupils to work and to secure good conduct. Prizes, decorations, rewards, titles, were offered as a means of attaining desired ends. Emulation is a natural instinct in mankind, and it may be utilized to stimulate endeavor and "foster ambition." The principle ever to be kept in mind should be _excellency without degrading others_. Schwickerath thinks that such was the spirit in which the Jesuits employed this incentive.[71] He admits, however, that there are dangers connected with prizes, and, on the whole, that certain methods of fostering emulation recommended by the _Ratio Studiorum_ are less suitable to northern countries and less in accordance with modern taste. While corporal punishment was allowed, it was generally administered by an official disciplinarian. It was seldom used, however, the discipline being mild and humane. =Criticism of Jesuit Education.=--As to the efficiency of the instruction in the Jesuit schools, opinions widely differ. Bacon and Descartes indorse it in highest terms, while Leibnitz, Voltaire, and others are equally strong in its condemnation. Bacon remarks, "As to whatever relates to the instruction of the young, we must consult the schools of the Jesuits, for there can be nothing that is better done." Leibnitz, on the other hand, says, "In the matter of education, the Jesuits have remained below mediocrity." Ranke, in speaking of the success of the Jesuit schools, says, "It was found that young persons learned more under them in half a year than with others in two years."