Brigid Brophy, in her fine study, Mozart the Dramatist, points out the origins of Masonic practices in the Eleusinian mysteries and Orphic myths of the ancient world. She documents the libretto's heavy debt to The Life of Sethos, a novel published in Paris in 1731 by the abb‚ Jean Terrasson. Purporting to be a translation from an ancient Greek source, this book recounts the initiation of its Egyptian hero into the mysteries of Isis. As Ms. Brophy points out, "Terrasson does not (but then one would not expect him to) explicitly connect his Isiac mysteries with Masonry; indeed, it is possible that the real influence was the other way about and the Masons borrowed hints for their own ritual from Terrasson's fictionalized Egypt."
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