⋅Doubt is the father of invention. /Galileo Galilei/

⋅You cannot teach a man anything; you can only help him find it within himself. /Galileo Galilei/

⋅All truths are easy to understand once they are discovered; the point is to discover them. /Galileo Galilei/

⋅By denying scientific principles, one may maintain any paradox. /Galileo Galilei/

⋅Facts which at first seem improbable will, even on scant explanation, drop the cloak which has hidden them and stand forth in naked and simple beauty. /Galileo Galilei/

⋅I do not feel obliged to believe that the same God who has endowed us with sense, reason, and intellect has intended us to forgo their use. /Galileo Galilei/

⋅I have never met a man so ignorant that I couldn't learn something from him. /Galileo Galilei/

⋅I think that in the discussion of natural problems we ought to begin not with the Scriptures, but with experiments, and demonstrations. /Galileo Galilei/

⋅I've loved the stars too fondly to be fearful of the night. /Galileo Galilei/

⋅If I were again beginning my studies, I would follow the advice of Plato and start with mathematics. /Galileo Galilei/

⋅In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. /Galileo Galilei/

⋅It is surely harmful to souls to make it a heresy to believe what is proved. /Galileo Galilei/

⋅It vexes me when they would constrain science by the authority of the Scriptures, and yet do not consider themselves bound to answer reason and experiment. /Galileo Galilei/

⋅Measure what is measurable, and make measurable what is not so. /Galileo Galilei/

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

⋅The Bible shows the way to go to heaven, not the way the heavens go. /Galileo Galilei/

⋅The Milky Way is nothing else but a mass of innumerable stars planted together in clusters. /Galileo Galilei/

⋅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. /Galileo Galilei/

⋅We cannot teach people anything; we can only help them discover it within themselves. /Galileo Galilei/

⋅We must say that there are as many squares as there are numbers. /Galileo Galilei/