Al-Ḥakīm al-Tirmidhī’s Kitāb Ithbāt al-‘Ilal

A paper read at the 1960 annual meeting of the American Oriental Society held in New Haven, Connecticut, and updated in July 2016.

It is in the third century after the hijrah that mysticism first begins to flourish in the Islamic world. This is the century which produced such great mystics as al-Muḥāsibī, al-Junayd, Abū Yazīd al-Bisṭāmī and al-Ḥallāj. To this century also belongs al-Ḥakīm al-Tirmidhī, who, although perhaps less well known than the others, was certainly the most prolific writer of them all, having written during his lifetime almost 60 different titles. Of these 60, two are particularly well known, and they are Khatm al-Awliyā’ or Khatm al-Wilāyah (the seal of the saints), and Kitāb al-‘Ilal (the book of reasons) or Ithbāt al-‘Ilal (the confirmation of reasons), which is the work I should like to discuss now.