"The greatest obstacle to progress in science is the blind adherence to authority."

"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."

"Without the knowledge of Greek, it is impossible to understand the Scriptures perfectly."

"The secrets of nature are not revealed to those who rely on books alone."

"The philosophers of the ancients, and especially the Arabs, have excelled us in many things."