According to Clement of Alexandria, he wrote what were called the "forty-two books of Hermes", covering all fields of knowledge.
ɐkˈoːɹdɪŋ tə klˈɛmənt ʌv ˌælɪɡzˈændɹiə, hiː ɹˈoʊt wʌt wɜː kˈɔːld ðə "fˈɔːɹɾitˈuː bˈʊks ʌv hˈɜːmiːz", kˈʌvɚɹɪŋ ˈɔːl fˈiːldz ʌv nˈɑːlɪdʒ.