In this case the most ancient testimony is posterior to the claimed occurrence some four hundred years, and is utterly inconsistent with the indisputable facts related by contemporary authors. The erudite Launoy, in his treatise _De Auctoritate Negantis Argumenti_, lays down the rule that a fact of a public nature not mentioned by any writer within two hundred years of its supposed occurrence is not to be believed. This is the same Launoy who waged war on the legends of the saints, claiming that much fabulous matter had crept into them. On this account he was called "Dénicheur des Saints"--the Saint-hunter or router--and the Abbé of St. Roch used to say, "I am always profoundly polite to Launoy, for fear he will deprive me of St. Roch." The general rule (Launoy's) so important in historical criticism is in perfect harmony with a great and leading principle of jurisprudence. In the Pope Joan incident the silence of all the writers of that age as to so remarkable a circumstance is to be fairly received as a _prerogative_ argument (Baconian philosophy) when set up against the numerous modern repetitions of the story. It may be taken as a general rule that the silence of contemporaries is the strongest argument against the truth of any given historical assertion, particularly when the fact asserted is strange and interesting, and this for the reason that man is ever prone to believe and recount the marvellous; and in the absence of early evidence, the testimony of later times is, for the same reason, only weaker. {6} Now this is in strict accordance with the principle of English common law, which demands the highest and rejects hearsay and secondary evidence; for scores of witnesses may depose in vain that they have heard of such a fact; the eye-witness is the prerogative instance. This is the logic of evidence. And now we find that what happened to Marianus Scotus also befell Polonus. He was entirely innocent of any mention of Joan! The passage exists in none of the oldest copies, and is wanting in all that follow the author's close and methodical plan of giving one line to each year of a pope's reign, so that, with fifty lines to the page as he wrote, each page covered precisely half a century. This method is entirely broken up in those MSS. which contain the passage concerning Joan, and the rage to get the passage in was such that in one copy (the Heidelberg MS.) Benedict III. is left out entirely and Joan put in his place. Dr. Döllinger and the learned Bayle concur in the opinion that the passage never had any existence in the original work of Polonus.