Galileo Galilei

E pur si muove. (And yet it moves.)

You cannot teach a man anything; you can only help him discover it in himself.

Philosophy is written in this grand book, the universe, which stands continually open to our gaze. But the book cannot be understood unless one first learns to comprehend the language and read the letters in which it is composed.

To be humane, we must ever be ready to pronounce that wise, ingenious and modest statement 'I do not know'.

It is a beautiful and delightful sight to behold the body of the Moon.

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

The prohibition of science would be contrary to the Bible, which in hundreds of places teaches us how the greatness and the glory of God shine forth marvelously in all His works.

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.

The universe cannot be read until we have learned the language and become familiar with the characters in which it is written.

In the sciences, the authority of thousands of opinions is not worth as much as one tiny spark of reason in an individual man.

Doubt is the father of invention.

Names and attributes must be accommodated to the essence of things, and not the essence to the names, since things come first and names afterwards.

What has philosophy got to do with measuring anything?

It is surely harmful to souls to make it a heresy to believe what is proved.

The greatest wisdom is to get to know oneself.

I render infinite thanks to God for being so kind as to make me alone the first observer of marvels kept hidden in obscurity for all previous centuries.

The motion of the Earth is undeniably a paradox.

To understand the Universe, you must understand the language in which it's written, the language of Mathematics.

The diversity of physical opinions offers a powerful and excellent method of ascertaining the truth.

I value the discovery of a single, even insignificant, truth more highly than all the argumentation on the highest questions which fails to reach a truth.