Derivation of the cause (takhrij al-manat)

Takhrij al-manat is the derivation of a ruling's cause by juristic effort, where a text or consensus gives the ruling but not its cause. ¹

Manat is the place where a ruling is attached, and in usul the manat of a ruling is its cause. Takhrij al-manat is the effort to establish the cause, as in arguing that a strong intoxicating quality is the cause of the prohibition of wine, or that taste is the cause of riba al-fadl in wheat. ¹ Munasaba is identifying the cause by showing a relation between the attribute and the ruling that a sound mind grasps without defects; drawing such a relation out is called takhrij al-manat. Takhrij al-manat is the broader term, since it may proceed by munasaba or otherwise. ¹

The Zahiris, the Shia and some Baghdadi Mu'tazilis reject acting on a derived cause. Al-Ghazali held that a derived cause may be known through allusion or the indication of the text, or through sabr; he held tahqiq al-manat agreed and tanqih al-manat accepted by most scholars. ¹ The fuller treatment is in the usul appendix.