From hence Casaubon infers, that this our author, who preaches virtue, and probity, and plain-dealing, ought to be studied principally by kings and ministers of state; and that youth, which are bred up to succeed in the management of business, should read him carefully, and imbibe him thoroughly, detesting the maxims that are given by Machiavel and others, which are only the instruments of tyranny. Furthermore, (continues he,) the study of truth is perpetually joined with the love of virtue; for there is no virtue which derives not its original from truth; as, on the contrary, there is no vice which has not its beginning from a lie. Truth is the foundation of all knowledge, and the cement of all societies; and this is one of the most shining qualities in our author. I was so strongly persuaded of this myself, in the perusal of the present history, that I confess, amongst all the ancients I never found any who had the air of it so much; and amongst the moderns, none but Philip de Commines.[24] They had this common to them, that they both changed their masters. But Polybius changed not his side, as Philip did: he was not bought off to another party, but pursued the true interest of his country, even when he served the Romans. Yet since truth, as one of the philosophers has told me, lies in the bottom of a well, so it is hard to draw it up: much pains, much diligence, much judgment is necessary to hand it us; even cost is oftentimes required; and Polybius was wanting in none of these.