Galileo Galilei

And yet it moves.

I have never met a man so ignorant that I could not learn something from him.

Given (...) that two truths can never contradict each other, the task of wise interpreters is to strive to find the true meanings of scriptural passages agreeing with those physical conclusions of which we are already certain and sure from clear sensory experience or from necessary demonstrations.

Measure what is measurable, and make measurable what is not so.

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.

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

By denying scientific principles, one may maintain any paradox.

The universe cannot be read until we have learnt the language and become familiar with the characters in which it is written. It is written in mathematical language, and the letters are triangles, circles and other geometrical figures, without which means it is humanly impossible to comprehend a single word.