fairly demonstrated; neither do they think it unworthy of them 

 to change their opinion if truth and undoubted demonstration 

 require them so to do; nor do they 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. 



My dear colleagues, I had no purpose to swell this treatise 

 into a large volume by quoting the names and writings of anato- 

 mists, or to make a parade of the strength of my memory, the 

 extent of my reading, and the amount of my pains; because I 

 profess both to learn and to teach anatomy, not from books 

 but from dissections; not from the positions of philosophers but 

 from the fabricof nature; and then because I do not think it right 

 or proper to strive to take from the ancients any honour that 

 is their due, nor yet to dispute with the moderns, and enter 

 into controversy with those who have excelled in anatomy and 

 been my teachers, I would not charge with wilful falsehood 

 any one who was sincerely anxious for truth, nor lay it to any 

 one's door as a crime that he had fallen into error. I avow myself 

 the partisan of truth alone; and I can indeed say that I have 

 used all my endeavours, bestowed all my pains on an attempt 

 to produce something that should be agreeable to the good, 

 profitable to the learned, and useful to letters. 

 Farewell, most worthy Doctors, 



And think kindly of your Anatomist, 

 William Harvey. 



(Translation by Robert Willis, M.D., 1847.) 



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