Istihsan

Istihsan is a method of Islamic legal reasoning that departs from an apparent analogy when a stronger proof or consideration supports a different ruling.

Qiyas: Qiyas is analogical legal reasoning that extends a ruling to a new case because it shares an effective cause with an established case. Istihsan departs from an apparent qiyas when another recognized justification is judged stronger.
Abu Hanifa: Abu Hanifa was an eighth-century Iraqi jurist and the eponymous founder of the Hanafi school of Islamic law. Hanafi legal thought became especially associated with the use of istihsan.
Istishab: Istishab is the presumption that an established legal state continues until evidence shows that it has changed. Unlike istihsan’s justified departure from analogy, istishab preserves an existing presumption.
Istisna: Istisna is a contract to manufacture or construct a specified item, with payment terms agreed by the parties. Its permissibility is often explained as an exception to analogy that would otherwise bar sale of an unmade item.
Muhammad al-Shaybani: Muhammad al-Shaybani was an early Hanafi jurist whose writings helped transmit and develop the school’s legal doctrine. His works preserve Hanafi reasoning in which istihsan has a recognized role.
Istihsan bi al-darura: Istihsan bi al-darura is a departure from analogy justified by necessity or hardship. Necessity is one of the grounds that can warrant an exception to an apparent analogy.
Hanafi school: The Hanafi school is a Sunni school of Islamic law founded on the teachings of Abu Hanifa and his students. Its jurists developed and defended istihsan as a legitimate form of legal reasoning.
Sadd al-dhara'i: Sadd al-dhara'i is the legal principle of blocking otherwise permissible means likely to lead to prohibited harm. It reaches protective rulings by a different route than choosing an exception to analogy.
Salam: Salam is a forward sale in which the buyer pays in advance for specified goods delivered later. Its accepted form illustrates how legal rules accommodate practical trade despite ordinary restrictions on deferred delivery.
Abu Yusuf: Abu Yusuf was a leading student of Abu Hanifa and the first chief judge of the Abbasid caliphate. As an early Hanafi authority, he helped shape the school that prominently employed istihsan.

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