The Roman History · Amm. 21.1.13

And because the ignorance of the vulgar often talks loudly, though ignorantly, against these ideas, asking why, if there were any faculty of foreseeing the future, one man should be ignorant that he would be killed in battle, or another that he would meet with some misfortune, and so on; it will be enough to reply that sometimes a grammarian has spoken incorrectly, or a musician has sung out of tune, or a physician been ignorant of the proper remedy for a disease; but these facts do not disprove the existence of the sciences of grammar, music, or medicine.

Ammianus Marcellinus · translated by C. D. Yonge · 1911 reprint
C. D. Yonge translation (preface dated February 1862); G. Bell and Sons, 1911; Project Gutenberg #28587
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