“Ignorance is of a peculiar nature; once dispelled, it is impossible to reestablish it. It is not originally a thing of itself, but is only the absence of knowledge; and though man may be kept ignorant, he cannot be made ignorant.”

“True ignorance is not the absence of knowledge, but the refusal to acquire it.”

“It is not enough that you understand in what ignorance man and beast live; you must also have and acquire the will to ignorance. You need to grasp that without this kind of ignorance life itself would be impossible, that it is a condition under which alone the living thing can preserve itself and prosper: a great, firm dome of ignorance must encompass you.”

“The learned man understands the ignorant for he was once ignorant himself. The ignorant man does not understand the learned for he has never been learned himself.”

“Neglect of mathematics work injury to all knowledge, since he who is ignorant of it cannot know the other sciences or things of this world. And what is worst, those who are thus ignorant are unable to perceive their own ignorance, and so do not seek a remedy.”

“You will search the world over and not find a nonsuperstitious community. As long as there is ignorance, there will be adherence to superstition. Dispelling ignorance is the only solution. That is why I teach.”