علل الحديث
ʿIlal al-Ḥadīth
Topic
The science of hidden defects in hadith: flaws in a report that look sound on the surface but weaken it.
What it means
ʿIlal is the plural of ʿilla, here a hidden defect. The science of ʿilal al-ḥadīth studies the qualities or circumstances that may weaken a report that otherwise seems sound. Examples include a break in a chain that is not apparent, a narrator who attributed to the Prophet (peace be upon him) the words of a Companion, or a mix-up of two chains. It is regarded as one of the most demanding branches of hadith criticism, since spotting such defects needs wide knowledge of narrators and their reports. Early critics such as Ali ibn al-Madini worked in it, and Ibn Abi Hatim al-Razi (d. 938) wrote a well-known work on the subject.
Term and Arabic as listed in Ismail al Faruqi, Toward Islamic English (International Institute of Islamic Thought, 1995), p. 50, listed as 'ILAL AL ḤADĪTH. The definition is restated here.