 In any case, a wider influence of Avicenna’s philosophy on Medieval Judaic thought appeared after 1150. The first significant case is that of Abraham Ibn Daud, living in Toledo between 1110 and 1180 circa. As it is clear from his philosophical work, the Exalted Faith (al-‘Aqida al-rafi’a, lost in its Judaeo-Arabic original, but preserved in two 14th-century Hebrew translations), he was the first Jewish Aristotelian, but surely employed as his main sources both Avicenna and al-Ghazali. As shown in recent studies by Amira Eran, and in particular in her book about the contents of Ibn Daud’s work (Eran 1998, 27), Avicennian influences appear mostly in book one of the Exalted Faith, where such philosophical themes as categories, matter and motion, souls and celestial bodies are studied. However, in treating these themes, Ibn Daud did not directly refer to the contents of Avicenna’s main extant encyclopedia, The Cure (al-Shifa’), but to his minor encyclopedia of logic, physics and metaphysics: The Salvation (al-Najat). Moreover, it might be suggested that in reality instead Ibn Daud employed al-Ghazali as his main source for constructing his own “Avicennism” rather than Avicenna himself (see below, 6), just as a number of later Medieval Jewish philosophers did, beginning with Maimonides. Maimonides appears to have regarded Avicenna not as a really direct and important philosophical source. Although clear echoes of Avicennian doctrines about the distinction between essence and existence, between necessary and contingent beings, as well as the well-known Avicennian proof of the existence of God, have been found in the Guide of the Perplexed (see Moses Maimonides 1962, 1:xciii-ciii), the explicit judgement of Maimonides about Avicenna’s thought appears to be substantially cool (for a different interpretation of this judgement, see however Dobbs-Weinstein 2002). In his letter to Samuel Ibn Tibbon, he affirms that “Avicenna’s books, although they are subtle and difficult, are not like those by al-Farabi; however, they are useful, and he too is an author whose words should be studied and understood” (Marx 1934–1935: 380).