INTRODUCTION

This and the following chapter are concerned with Shī'ite conceptions of forbidding wrong. Shī'ite Islam is a ramified phenomenon. But of the numerous Shī'ite sects that have existed at one time or another, only two will receive sustained attention in this study: the Zaydīs in this chapter, and the Imāmīs in the next. The reasons for this limitation are not far to seek. These sects have preserved large bodies of religious literature down to the present day, so that their doctrines are accessible to serious study. At the same time, they have always been sufficiently close to the mainstream of Islamic thought to support a body of ideas comparable to those of Sunnī Islam. The other major Shī'ite sect of Islamic history, the lsmā'īlīs, has less to offer on both counts, but I shall devote a short excursus to it at the end of the chapter on the Imāmīs.

The Zaydīs and Imāmīs have much in common. Both are Shī'ite sects, both developed elaborate traditions of legal scholarship, and both adopted Mu'tazilite theology. But they also diverged in significant respects. The most important of these differences for the purposes of this study concern religious politics. Here both sects were firmly committed to doctrines of ‘Alid power, but they disagreed on two basic questions. The first was precisely who among the ‘Alids should rule: where the Zaydīs saw the family of the Prophet as a large and continuing pool of potential rulers, the Imāmīs were committed to a single line of imams which eventually ended in occultation.