The human understanding, when any preposition has been once laid down... forces everything else to add fresh support and confirmation; and although more cogent and abundant instances may exist to the contrary, yet it either does not observe them or it despises them, or it gets rid of and rejects them by some distinction, with violent and injurious prejudice, rather than sacrifice the authority of its first conclusions.

Lies are sufficient to breed opinion, and opinion brings on substance.

I always think of myself not so much as a painter but as a medium for accident and chance.

But I account the use that a man should seek of the publishing of his own writings before his death, to be but an untimely anticipation of that which is proper to follow a man, and not to go along with him.

There arises from a bad and unapt formation of words a wonderful obstruction to the mind.

They are the best physicians, who being great in learning most incline to the traditions of experience, or being distinguished in practice do not reflect the methods and generalities of art.

But by far the greatest hindrance and aberration of the human understanding proceeds from the dullness, incompetency, and deceptions of the senses; in that things which strike the sense outweigh things which do not immediately strike it, though they be more important. Hence it is that speculation commonly ceases where sight ceases; insomuch that of things invisible there is little or no observation.