For example...

For example, Ustadh Mubammad al-Dawalibi in his book al-Madkhal ila `ilm usul al-fiqh, describes the sources for inference of ahkam as: (1) the Book, (2) the Sunnah, (3) ijma` and (4) ijtihad. This view has been accepted by Muhammad Rashid Rida, the renowned author of al-Wahy al-Muhammadi.

Furthermore, according to that which has been ascribed to Malik ibn Anas al-'Asbahi the sources of ijtihad comprise: (1) the Book (2) the Sunnah (3) ijma` (4) qiyas, (5) istihsan (6) the principle of istislah, (7) al-madhhab al-Sahabi, (8) sadd al-dhara’i (9) fath 'al-dhara’i, (10) qanun al-salaf, (11) istishab, (12) istiqra' (13) bara'ah asliyyah, (14) `urf, (15) istidlal, etc.

However, we will confine ourselves to the above views, proceeding to examine the impact of these different views of ijtihad and legal deduction. It is evident that the theoretical differences about the sources of ijtihad should lead the jurisprudents, in the process of legal deduction vis-a-vis new problems and developments, to adopt different courses resulting in divergent fatawa. Hence we find different schools of thought in the history of jurisprudence and ijtihad.

However, of the many schools of thought, only five came to be officially recognized, namely, the Ja'fari, the Hanafi, the Maliki, the Shafi'i, and the Hanbali. With the passage of time the others have been abandoned and forgotten. The Sources of Ijtihad: We will now discuss and examine the sources of ijtihad, one by one, in order to gain a better acquaintance with the basic sources for inferring and deducing the ahkam.

As indicated earlier in our discussion, the very first source of ijtihad is the Book. Accordingly, the subject of discussion in this article will be the Qur'an, held in common accord by jurisprudents of all schools of thought in Islam (including, besides the well-known five, the Zahiri, Jariri, Tamimi, Nakh`i, Awza’i, Thawri, Laythi, Kalbi, and other schools now extinct) as the primary source of reference for identifying the ahkam of the Shari'ah.

If any occasional difference among the schools of thought is dis­cernible concerning the Qur'an, it relates to opinions concerning the interpretation of the verses, and other problems like naskh (abrogation), tahr'if, the criteria of amr and nahy, `amm, mutlaq, etc. However, this procedural aspect does not affect the purpose of our present discussion.