Avicenna derives other attributes of the necessary existent in multiple texts in order to justify its identification with God. He shows that the necessary existent must also be immaterial, intellective, powerful, generous, of pure good (khayr mahd), willful (irada), "wealthy" or "sufficient" (ghani), and self-subsistent (qayyum), among other qualities. These attributes often correspond to the epithets of God found in the Quran. In discussing some of the attributes' derivations, Adamson commented that "a complete consideration of Avicenna's derivation of all the attributes ... would need a book-length study". In general, Avicenna derives the attributes based on two aspects of the necessary existent: (1)its necessity, which can be shown to imply its sheer existence and a range of negations (e.g. not being caused, not being multiple), and (2)its status as a cause of other existents, which can be shown to imply a range of positive relations (e.g. knowing and powerful).
