Various people had published transcripts of bits of ancient music, and had been applauded at the concerts where their transcripts were performed; and they did not like my saying that twenty notes in twenty-one were wrong, and the twenty-first was doubtful. Anyone can calculate the intervals between the notes by means of logarithms and the ratios given by Ptolemy and other ancient authors. These people told me volubly that this was only mathematics--“lascia le muse, e studia le matematiche.” They said that Aristoxenus must have used the tempered scale, as he assumes that six tones make an octave. Euclid, _Sectio Canonis_, prop. 9, proves with his usual precision that six tones are greater than an octave. Ptolemy, _Harmonica_, i. 9, says that the Aristoxenians should either have accepted what was proved, or set up something else to take its place; and he would hardly have said that, had they set up the tempered scale. I have always felt that, if an opinion was worth publishing, it was worth defending; and that was why I defended my views about Greek music in the _Revue Critique_ and elsewhere, and have also defended my views on many other things. Critics often change their tone, when put on their defence. There was a professor of theology at Jena, who was displeased with something that I wrote, and he pitched into me, _Berliner Philologische Wochenschrift_, 18 June 1898. I wrote an Entgegnung, which appeared there, 27 August 1898, with an Erwiderung from him. I remarked that “was er ein Wasserstrahl nennt, ist nicht anderes als der Heilige Geist,” corrected him on other points, and finished off with “in der That scheint er von der Litteratur der Sache ebensowenig zu wissen als von altchristlicher Kunst.” In his reply he was an injured innocent, although he had come down on me as if he were a Pope and Œcumenical Council all rolled up into one. I had been writing about some portraits of Christ that can probably be dated at 258 A.D., or shortly after that; and I had used them in support of my opinion that Christ was only a little over twenty years of age at the date of the Crucifixion. I did not expect people to acquiesce in this without demur; but the theologians treated dates as dogmas. I cannot see the merit of believing that something happened in one way, if it happened in another way, or did not happen at all.