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.

— Galileo Galilei

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

— 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

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

— 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 can be measured, and make measurable what cannot be measured.

— Galileo Galilei

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

— Galileo Galilei

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

— Galileo Galilei

Philosophy [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 Galilei

See 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 Galilei