On the matter of the incest there is no word in Sanuto; but there is mention of Doña Sancia’s indiscretions, and the suggestion that, through jealousy on her account, it was rumoured that the murder had been committed--another proof of how vague and ill-defined the rumours were.
PIETRO MARTIRE D’ANGHIERA writes from Burgos, in Spain, that he is convinced of the fratricide. It is interesting to know of that conviction of his; but difficult to conceive how it is to be accepted as evidence.
If more needs to be said of him, let it be mentioned that the letter in which he expresses that conviction is dated April 1497--two months before the murder took place! So that even Gregorovius is forced to doubt the authenticity of that document.
GUICCIARDINI is not a contemporary chronicler of events as they happened, but an historian writing some thirty years later. He merely repeats what Capello and others have said before him. It is for him to quote authorities for what he writes, and not to be set up as an authority. He is not reliable, and he is a notorious defamer of the Papacy, sparing nothing that will serve his ends. He dilates with gusto upon the accusation of incest.
Lastly, PANVINTO is in the same category as Guicciardini. He was not born until some thirty years after these events, and his History of the Popes was not written until some sixty years after the murder of the Duke of Gandia. This history bristles with inaccuracies; he never troubles to verify his facts, and as an authority he is entirely negligible.
In the valuable Diarium of Burchard there is unfortunately a lacuna at this juncture, from the day after the murder (of which he gives the full particulars to which we have gone for our narrative of that event) until the month of August following. And now we may see Gregorovius actually using silence as evidence. He seizes upon that lacuna, and goes so far as to set up the tentative explanation that Burchard “perhaps purposely interrupted his Diary that he might avoid mentioning the fratricide.”
If such were the case, it would be a strange departure from Burchard’s invariable rule, which is one of cold, relentless, uncritical chronicling of events, no matter what their nature. Besides, any significance with which that lacuna might be invested is discounted by the fact that such gaps are of fairly common occurrence in the course of Burchard’s record. Finally it remains to be shown that the lacuna in question exists in the original diaries, which have yet to be discovered.