The diagram below summarises the five-grade classification of aḥādīth developed in the preceding entries: Ṣaḥīḥ li-dhātihi and ḥasan li-dhātihi as the two intrinsically sound categories, ṣaḥīḥ li-ghayrihi and ḥasan li-ghayrihi as their externally strengthened counterparts (a ḥasan li-dhātihi rising to ṣaḥīḥ, and a ḍaʿīf rising to ḥasan, through corroborating routes), and ḍaʿīf as the residual class for narrations that fail the criteria of acceptance.
Summary of aḥādīth in terms of acceptance and rejection
Khabar al-wāḥid is categorised, with respect to acceptance and rejection, into al-ṣaḥīḥ, al-ḥasan, and al-ḍaʿīf.
When the routes of a ḥasan li-dhātihi narration multiply, the ḥadīth is upgraded to al-ṣaḥīḥ li-ghayrihi (the sound by virtue of something other than itself).
Ḥadīth, in the muḥaddithūn's classification, is of two categories: al-mutawātir and khabar al-wāḥid.
If a ḥadīth of slight weakness comes through multiple routes, it becomes al-ḥasan li-ghayrihi (the fair by virtue of something other than itself).
