 In a few instances in his Book of Definitions, Israeli diverges from models given by his forerunner al-Kindi. Although Israeli posits a first intellect and a second intellect, Israeli describes three hypostases of intellect. First intellect, the entity which emerges from the conjunction of first matter and first form, contains all subsequent forms, which emanate from the first intellect and determine the specificality of all substances and knows all things eternally. The secondary hypostasis of intellect is actually in the rational soul, and is potential intellect before it passes into the actual intellect of the first intellect. The “second intellect” (actually the third hypostasis of intellect) is a faculty of the rational soul, which via sense perception and imagination (the “internal senses”) conveys information to the higher hypostasis in the rational soul. The second intellect of the rational soul unites with the objects of its intellection in a spiritual, non-corporeal sense and similarly, upon conveyance of the intellection to the higher intellect of the rational soul, the higher hypostasis of intellect within the rational soul also spiritually unites with the objects of its intellection. (Altmann and Stern, Isaac Israeli, pp. 36–7) Since Israeli here diverges from al-Kindi, Stern accuses Israeli of a clumsy misreading of the latter. (Isaac Israeli, p. 39) However, since Israeli’s description of internal senses largely mirrors the description in John of Damascus’ De Fide Orthodoxa, (Book II, Chapter 20) it is likely that Israeli derived his overall schema of intellection from another source. While Stern rejected the connection between the text of John of Damascus and Israeli (Isaac Israeli, p. 59), Harry Wolfson rejoined that De Fida Orthodoxa was available in Arabic translation in the tenth century (Wolfson, 1961, p. 279). Further, it is possible that Israeli was drew his conception from another lost source common to himself and John of Damascus, or from a lost Arabic commentator on the latter.