"The common herd of students knows nothing of the sciences, but only of words."

"The study of astrology is necessary for medicine, and for the understanding of the future."

"The study of music, as it is commonly taught, is of little utility."

"Many things are believed on mere custom, without any reason or proof."

"The study of optics is of the greatest utility, for it teaches us to understand the nature of light, and of all things that are visible."