Introduction to the Science of Hadith Introduction to the Science of Hadith (Ibn al-Ṣalāḥ's) Introduction to the Science of Hadith () is a 13th-century book written by `Abd al-Raḥmān ibn `Uthmān al-Shahrazūrī, better known as Ibn al-Ṣalāḥ, which describes the Islamic discipline of the science of hadith, its terminology and the principals of biographical evaluation. A hadith is a recorded statement, action or approval of the Islamic prophet Muhammad which serves as the second source of legislature in Islamic law. The science of hadith that this work describes contains the principles with which a hadith specialist evaluates the authenticity of individual narrations. "The Introduction" comprises 65
Hadith terminology in and of itself"with the same definition a "ṣaḥīḥ hadith" except that the competence of one of its narrators is less than complete; while a "hadith" that is "ḥasan ligharihi" ("ḥasan due to external factors") is determined to be "ḥasan" due to corroborating factors such as numerous chains of narration. He states that it is then comparable to a "ṣaḥīḥ hadith" in its religious authority. A "ḥasan hadith" may rise to the level of being "ṣaḥīḥ" if it is supported by numerous "isnād" (chains of narration); in this case that "hadith" would be "ḥasan lithatihi" (""ḥasan" in and of itself")