There are several who have heard yourself either admit, on interrogation, that that Epistle is yours, or declare the fact spontaneously....
If you ask on what evidence I, at such a distance, make these statements, and how they can have become so certain to myself, I reply that it is not on the evidence of rumour merely, but partly on that of most scrupulous witnesses who have most solemnly made the assertions to myself personally, partly on that of letters written either to myself or to others.

I will quote the very words of the letters, but will not give the names of the writers, considering that unnecessary in matters of such notoriety independently.

Here you have first an extract from a letter to me from the Hague, the writer of which is a man of probity and had no common means of investigating this affair:--'I have ascertained beyond doubt (_exploratissimum mihi est_) that Morus himself offered the copy of the _Clamor Regii Sanguinis_ to some other printers before Ulac received it, that he superintended the correction of the errors of the press, and that, as soon as the book was finished, copies were given and distributed by him to not a few.'...

Take again the following, which a highly honourable and intelligent man in Amsterdam writes as certainly known to himself and as abundantly witnessed there:--'It is most certain that almost all through these parts have regarded Morus as the author of the book called _Regii Sanguinis Clamor_; for he corrected the sheets as they came from the press, and some copies bore the name of Morus subscribed to the Dedicatory Epistle, of which also he was the author.

He himself told a certain friend of mine that he was the author of that Epistle: nay there is nothing more certain than that Morus either assumed or acknowledged the authorship of the same.' ...