Galileo Galilei

"I notice that young men go to the universities in order to become doctors or philosophers or anything, so long as it is a title, and that many go in for those professions who are utterly unfit for them, while others who would be very competent are prevented by business or their daily cares, which keep them away from letters."

"If I were again beginning my studies, I would follow the advice of Plato and start with mathematics."

"In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual."

"Nature is relentless and unchangeable, and it is indifferent as to whether its hidden reasons and actions are understandable to man or not."

"The Bible shows the way to go to heaven, not the way the heavens go."

"The sun, with all those planets revolving around it and dependent on it, can still ripen a bunch of grapes as if it had nothing else in the universe to do."