William Harvey

"The heart of animals is the foundation of their life, the sovereign of everything within them, the sun of their microcosm, that upon which all growth depends, from which all power proceeds."

"Very many maintain that all we know is still infinitely less than all that still remains unknown; nor do philosophers pin their faith to others' precepts in such wise that they lose their liberty, and cease to give credence to the conclusions of their proper senses. Neither do they swear such fealty to their mistress Antiquity that they openly, and in sight of all, deny and desert their friend Truth. But even as they see that the credulous and vain are disposed at the first blush to accept and believe everything that is proposed to them, so do they observe that the dull and unintellectual are indisposed to see what lies before their eyes, and even deny the light of the noon-day sun."

"The studious and good and true, never suffer their minds to be warped by the passions of hatred and envy, which unfit men duly to weigh the arguments that are advanced in behalf of truth, or to appreciate the proposition that is even fairly demonstrated. Neither do they think it unworthy of them to change their opinion if truth and undoubted demonstration require them to do so. They do not esteem it discreditable to desert error, though sanctioned by the highest antiquity, for they know full well that to err, to be deceived, is human; that many things are discovered by accident and that many may be learned indifferently from any quarter, by an old man from a youth, by a person of understanding from one of inferior capacity."

"I profess both to learn and to teach anatomy, not from books but from dissections; not from positions of philosophers but from the fabric of nature."

"I avow myself the partisan of truth alone."

"As art is a habit with reference to things to be done, so is science a habit in respect to things to be known."

"I appeal to your own eyes as my witness and judge."

"Man comes into the world naked and unarmed, as if nature had destined him for a social creature, and ordained him to live under equitable laws and in peace; as if she had desired that he should be guided by reason rather than be driven by force; therefore did she endow him with understanding, and furnish him with hands, that he might himself contrive what was necessary to his clothing and protection. To those animals to which nature has given vast strength, she has also presented weapons in harmony with their powers; to those that are not thus vigorous, she has given ingenuity, cunning, and singular dexterity in avoiding injury."

"Few would have predicted that the discovery of the circulation of the blood would have changed the way philosophers view the world, theologians conceive of God, or astronomers look at the stars, yet all of that happened."

"Harvey sought for truth in Truth's own book — Creation — which by God himself was writ; And wisely thought 'twas fit Not to read comments only upon it, But on th' original itself to look. Methinks in Art's great circle others stand Lock'd up together hand in hand: Every one leads as he is led, The same bare path they tread, A dance like that of Fairies, a fantastic round, With neither change of motion nor of ground. Had Harvey to this road confined his wit, His noble circle of the blood had been untrodden yet."

"Harvey was not content merely to gather knowledge; he digested and arranged it under the guidance of the faculties which compare and reason. … Harvey appears to have possessed, in a remarkable degree, the power of persuading and conciliating those with whom he came in contact. In the whole course of his long life we hear nothing either of personal enemies or personal enmities … one of the great men whom God, in virtue of his eternal laws, bids to appear on earth from time to time to enlighten, and to ennoble mankind."