“We naturally like what we have been accustomed to, and are attracted towards it. [...] The same is the case with those opinions of man to which he has been accustomed from his youth; he likes them, defends them, and shuns the opposite views.”

“WHEN reading my present treatise, bear in mind that by "faith" we do not understand merely that which is uttered with the lips, but also that which is apprehended by the soul, the conviction that the object [of belief] is exactly as it is apprehended. If, as regards real or supposed truths, you content yourself with giving utterance to them in words, without apprehending them or believing in them, especially if you do not seek real truth, you have a very easy task as, in fact, you will find many ignorant people professing articles of faith without connecting any idea with them.”

“If a person studies too much and exhausts his reflective powers, he will be confused, and will not be able to apprehend even that which had been within the power of his apprehension. For the powers of the body are all alike in this respect.”

“In the realm of Nature there is nothing purposeless, trivial, or unnecessary”

“For the elements have the property of moving back to their place in a straight line, but they have no properties which would cause them to remain where they are, or to move other-wise than in a straight line, These rectilinear motions of these four elements when returning to their original place are are of two kinds, either centrifugal,vziz.>the motion of the air and the fire; or centripedal,viz.> the motion of the earth, and the water; and when the elements have reached their original place, they remain at rest.”

“From early youth we are accustomed to hearing falsified reports, and our minds have been saturated with prejudice for centuries, to the extent that we guard the fantastic lies like a treasure – so that in the end the truth becomes unbelievable and the lie appears to be true.”

“Do not consider it proof just because it is written in books, for a liar who will deceive with his tongue will not hesitate to do the same with his pen.”