Hadith of the Quran and Sunnah authenticity. The Shi'a claim that this hadith is the most authentic of hadiths, claiming that it has been narrated by over 35 companions of Muhammad. The "Hadith al-Thaqalayn" is used by the Shi'a, among other reasons, to support their belief of Ali's succession to Muhammad. Shi'as view this hadith as a clear indication that Muhammad wished to keep the matter of leadership within his own family, starting with his cousin Ali. They believe that Muhammad was clearly indicating that only the "Ahl al-Bayt" have a right to authority and leadership. It is based on this claim that the Shi'as reject
Introduction to the Science of Hadith adding six terms in the process). The first pertains to the "matn" (text) of the hadith and its three divisions and 30 types. The three divisions are "ṣaḥīḥ", "ḥasan", and "ḍa`īf". The thirty types include those mentioned in hadith terminology and others. The second deals with the "isnād" (chain of narration) and comprises 11 types. These types generally fall within the discipline of biographical evaluation. The third category includes six types: the qualifications necessary for conveying hadith, the manners in which they are transmitted, the transcription of hadith, and the etiquette of the narrator and of the student. The fourth