Copernicus passed away that day in ignorance that his life's work appeared before the world not as a truth but as an hypothesis; for there had been inserted an anonymous preface "ad lectorem de hypothesibus huius opera" stating this was but another hypothesis for the greater convenience of astronomers.[125] "Neque enim necesse est eas hypotheses esse veras, imo ne verisimiles quidem, sed sufficit hoc unum, si calculum observationibus congruentem exhibeant."[126] For years Copernicus was thought to have written this preface to disarm criticism. Kepler sixty years later (1601) called attention to this error,[127] and quoted Osiander's letters to Copernicus and to Rheticus of May, 1541, suggesting that the system be called an hypothesis to avert attacks by theologians and Aristotelians. He claimed that Osiander had written the preface; but Kepler's article never was finished and remained unpublished till 1858.[128] Giese and Rheticus of course knew that the preface falsified Copernicus's work, and Giese, highly indignant at the "impiety" of the printer (who he thought had written it to save himself from blame) wrote Rheticus urging him to write another "præfatiunculus" purging the book of this falsehood.[129] This letter is dated July 26, 1543, and the book had appeared in April. Apparently nothing was done and the preface was accepted without further challenge. [Footnote 125: Copernicus: _De Revolutionibus_, I. "To the reader on the hypotheses of this book."] [Footnote 126: "For it is not necessary that these hypotheses be true, nor even probable, but this alone is sufficient, if they show reasoning fitting the observations."] [Footnote 127: Kepler: _Apologia Tychonis contra Ursum_ in _Op. Om._: I, 244-246.] [Footnote 128: Prowe: II, 251, note.] [Footnote 129: Ibid: II, 537-9.] It remains to ask whether people other than Copernicus's intimates had known of his theory before 1543. Peucer, Melancthon's nephew, declared Copernicus was famous by 1525,[130] and the invitation from the Lateran Council committee indicates his renown as early as 1514. In Vienna in 1873[131] there was found a _Commentariolus_, or summary of his great work,[132] written by Copernicus for the scholars friendly to him. It was probably written soon after 1530, and gives a full statement of his views following a series of seven axioms or theses summing up the new theory. This little book probably occasioned the order from Pope Clement VII in 1533 to Widmanstadt to report to him on the new scheme.[133] This Widmanstadt did in the papal gardens before the Pope with several of the cardinals and bishops, and was presented with a book as his reward. [Footnote 130: Ibid: II, 273.] [Footnote 131: Ibid: II, 286-7.] [Footnote 132: A second copy was found at Upsala shortly afterwards, though for centuries its existence was unknown save for two slight references to such a book, one by Gemma Frisius, the other by Tycho Brahe. Prowe: II, 284.] [Footnote 133: Ibid: II, 273-4.]