 Perhaps the most important figure of the Ismā‘īlīs tradition, one who was both poet and philosopher, is Nāṣir-i Khusraw (1004–c.1072 CE). Whether in his collection of mystical and didactic poems known as Divān, or his mystically oriental works such as The Sum of the Two Wisdoms (Jāmi‘ al-ḥikmattayīn) and Knowledge and Liberation (Gushāyesh wa rahāyesh), he relentlessly offers advice on the catharsis of the soul and the pursuing of the spiritual journey. Nāṣir-i Khusraw’s attempt to reconcile Sufism and reason is seen in his The Sum of the Two Wisdoms, where he argues that the “sages of real religion” (ḥukamāy-i dīn-i ḥaqq) and the philosophers are in agreement. For Nāṣir-i Khusraw, the science of the soul is the way to attain real knowledge, knowledge which transcends the difference between the perceiver and perception. He writes: