The tradition of philosophy in the Persian-speaking world is extraordinarily rich, creative and diverse. This anthology, which is divided into three volumes, aims to communicate something of that richness and diversity. The term 'philosophy' is understood to in its widest sense to include theological debate, philosophical Sufism and philosophical hermeneutics (ta'wil). Extending over a period of more than two millennia, and showcasing translations by well-established scholars, the anthology offers full bibliographical references throughout. For anyone interested in exploring, in all their varied manifestations, the fascinating philosophical traditions of Persia, such a wide-ranging and ambitious work will be an indispensable resource. Volume 2 covers five centuries of Ismaili philosophy, and includes extracts from outstanding Ismaili works including the "Rasa'il Ikhwan al-Safa" ("Treatises of the Brethren of Purity") and the philosophical odes of Nasir Khusraw. It is of great siginificance that, in the early centuries of Islam, philosophers were influenced by Pythagorean and Hermetic ideas, which are usually associated with Shi'i thought in general and Ismailism in particular. Ismaili philosophy at this time was able to integrate strands of Greco-Alexandrian thought such as Hermeticism and Neo-Pythagoreanism, as well as aspects of Mazdaeism and Manichaeism. It also showed marked interest in Neo-platonism.