The Prince by Niccolo Machiavelli Chapter 7 Page 18

Julius II, in respect of whom he chose badly. Because, as I have said already, though he could not secure the election he desired, he could have prevented any other; and he ought never to have consented to the creation of any one of those Cardinals whom he had injured, or who on becoming Pope would have reason to fear him; for fear is as dangerous an enemy as resentment. Those whom he had offended were, among others, San Pietro ad Vincula, Colonna, San Giorgio, and Ascanio; all the rest, excepting d’Amboise and the Spanish Cardinals (the latter from their connexion and obligations, the former from the power he derived through his relations with the French Court), would on assuming the Pontificate have had reason to fear him. The duke, therefore, ought, in the first place, to have laboured for the creation of a Spanish Pope; failing in which,