But what exceeds all wonders, I have discovered four new planets and observed their proper and particular motions, different among themselves and from the motions of all the other stars; and these new planets move about another very large star [Jupiter] like Venus and Mercury, and perchance the other known planets, move about the Sun. As soon as this tract, which I shall send to all the philosophers and mathematicians as an announcement, is finished, I shall send a copy to the Most Serene Grand Duke, together with an excellent spyglass, so that he can verify all these truths.
Galileo GalileiPhilosophy [nature] is written in that great book which ever is before our eyes -- I mean the universe -- but we cannot understand it if we do not first learn the language and grasp the symbols in which it is written. The book is written in mathematical language, and the symbols are triangles, circles and other geometrical figures, without whose help it is impossible to comprehend a single word of it; without which one wanders in vain through a dark labyrinth.
Galileo GalileiI think that in the discussion of natural problems we ought to begin not with the Scriptures, but with experiments, and demonstrations.
Galileo GalileiSee now the power of truth; the same experiment which at first glance seemed to show one thing, when more carefully examined, assures us of the contrary.
Galileo GalileiScience proceeds more by what it has learned to ignore than what it takes into account.
Galileo GalileiWhat ever the course of our lives, we should recieve them as the highest gift from the hand of God, in which equally reposed the power to do nothing whatever for us. Indeed, we should accept misfortune not only in thanks, but in infinite gratitude to Providence, which by such means detaches us from an excessive love for Earthly things and elevates our minds to the celestial and divine.
Galileo Galilei